U.S. patent application number 11/888512 was filed with the patent office on 2009-02-05 for mobile station and methods for diagnosing and modeling site specific effluent treatment facility requirements.
This patent application is currently assigned to Triwatech, L.L.C.. Invention is credited to Robert Kohlheb, Gyorgy Lipovszki, Reginald A. Wiemers, Peter H. Zahn.
Application Number | 20090032446 11/888512 |
Document ID | / |
Family ID | 40304670 |
Filed Date | 2009-02-05 |
United States Patent
Application |
20090032446 |
Kind Code |
A1 |
Wiemers; Reginald A. ; et
al. |
February 5, 2009 |
Mobile station and methods for diagnosing and modeling site
specific effluent treatment facility requirements
Abstract
A mobile station and methods are disclosed for diagnosing and
modeling site specific effluent treatment facility requirements to
arrive at a treatment regimen and/or proposed commercial plant
model idealized for the particular water/site requirements. The
station includes a mobile platform having power intake, effluent
intake and fluid outflow facilities and first and second suites of
selectably actuatable effluent pre-treatment apparatus. An effluent
polishing treatment array is housed at the station and includes at
least one of nanofiltration, reverse osmosis and ion-exchange
stages. A suite of selectively actuatable post-treatment apparatus
are housed at the station. Controls are connected at the station
for process control, monitoring and data accumulation. A plurality
of improved water treatment technologies are also disclosed.
Inventors: |
Wiemers; Reginald A.;
(Littleton, CO) ; Kohlheb; Robert; (Majori,
HU) ; Lipovszki; Gyorgy; (Verbena, HU) ; Zahn;
Peter H.; (Littleton, CO) |
Correspondence
Address: |
HAROLD A. BURDICK
Suite E, 6676 Gunpark Drive
Boulder
CO
80301
US
|
Assignee: |
Triwatech, L.L.C.
|
Family ID: |
40304670 |
Appl. No.: |
11/888512 |
Filed: |
August 1, 2007 |
Current U.S.
Class: |
210/85 |
Current CPC
Class: |
C02F 2201/008 20130101;
Y02W 10/15 20150501; C02F 9/00 20130101; C02F 2209/00 20130101;
B01D 61/025 20130101; C02F 1/66 20130101; C02F 2209/005 20130101;
C02F 1/38 20130101; B01D 61/022 20130101; C02F 1/20 20130101; B01D
65/02 20130101; C02F 2001/007 20130101; C02F 1/441 20130101; C02F
2209/006 20130101; C02F 2209/008 20130101; C02F 1/52 20130101; C02F
1/442 20130101; B01D 61/027 20130101; C02F 2103/365 20130101; B01D
61/02 20130101; B01D 19/0036 20130101; C02F 1/42 20130101; C02F
1/463 20130101; C02F 3/082 20130101; Y02W 10/10 20150501 |
Class at
Publication: |
210/85 |
International
Class: |
B01D 36/00 20060101
B01D036/00 |
Claims
1. A mobile station for diagnosing and modeling site specific
effluent treatment facility requirements comprising: a mobile
platform including power intake, effluent intake and fluid outflow
facilities; a first suite of selectably actuatable effluent
pre-treatment apparatus housed by said mobile platform and
connected with said effluent intake facility of said mobile
platform; an effluent polishing treatment array housed by said
mobile platform and connected with said suite of pre-treatment
apparatus; a suite of selectably actuatable effluent post-treatment
apparatus housed by said mobile platform and connected with said
effluent polishing treatment array and said fluid outflow facility
of said mobile platform; and control means connectable with said
power intake facility of said mobile platform for process control
and data accumulation to thereby optimize a site specific effluent
treatment regimen and establish a site specific effluent treatment
facility model.
2. The mobile station of claim 1 wherein said control means
includes data input establishing site specific effluent quality
parameters and output establishing treatment parameters.
3. The mobile station of claim 2 further comprising effluent
testing means for initial and ongoing evaluation of effluent
quality at selected treatment intervals connected with said control
means.
4. The mobile station of claim 1 further comprising a second suite
of selectably actuatable effluent pre-treatment apparatus housed by
said mobile platform and operationally associated with said first
suite of pre-treatment apparatus, said second suite of
pre-treatment apparatus including chemical treatment apparatus,
membrane aeration apparatus and electrocoagulation apparatus.
5. The mobile station of claim 1 wherein said first suite of
pre-treatment apparatus includes membrane aeration apparatus,
degassification apparatus and filtration apparatus.
6. The mobile station of claim 1 wherein said effluent polishing
treatment array includes nanofiltration and reverse osmosis
treatment stages.
7. The mobile station of claim 1 wherein said suite of
post-treatment apparatus includes filtration apparatus, sodium
absorption ratio compensation apparatus, UV treatment apparatus and
aeration apparatus.
8. A temporary facility for water quality analysis, treatment
modeling, selective contaminated water processing, and data
accumulation at a particular treatment site to arrive at a proposed
commercial water treatment plant model idealized for the particular
water/site requirements, said facility comprising: a first suite of
selectably actuatable effluent pre-treatment apparatus connected
with a feed water intake; a second suite of selectably actuatable
effluent pre-treatment apparatus operationally associated with said
first suite of pre-treatment apparatus; a water polishing treatment
array connected to receive feed water after selected processing at
said first and second suites of pre-treatment apparatus, said water
polishing treatment array including at least one of a membrane
treatment array and an ion-exchange treatment array; a suite of
selectably actuatable post-treatment apparatus connected to receive
water processed through said water polishing treatment array and
providing therefrom a treated water outflow; and control means
connectable with said first and second suites of pre-treatment
apparatus, said water polishing treatment array and said suite of
post treatment apparatus for process control and data accumulation
to thereby optimize a site specific water treatment regimen and
establish the site specific proposed commercial water treatment
plant model.
9. The facility of claim 8 further comprising a feed water quality
evaluation and process quality monitoring input to said control
means, said input including an automated multi-stage water quality
testing and reporting regime.
10. The facility of claim 8 wherein said first suite of
pre-treatment apparatus includes membrane aeration apparatus,
density reduction apparatus, degassification apparatus including
venturi gas evacuation, fine filtration apparatus, clarification
apparatus, and sludge concentration apparatus.
11. The facility of claim 8 wherein said second suite of
pre-treatment apparatus includes chemical treatment apparatus,
membrane aeration apparatus, ionization apparatus,
electrocoagulation apparatus, cyclone separation apparatus, and
degassing apparatus.
12. The mobile station of claim 1 wherein said membrane treatment
array of said water polishing treatment array includes
nanofiltration and reverse osmosis treatment stages utilizing high
speed crossflow pumping at both said stages and high frequency
membrane separation at said nanofiltration stage.
13. The mobile station of claim 1 wherein said suite of
post-treatment apparatus includes activated carbon filtration,
sodium absorption ratio compensation apparatus, UV disinfection
apparatus and membrane aeration apparatus.
14. A method for diagnosing and modeling site specific water
treatment facility requirements to arrive at a proposed commercial
plant model idealized for the particular water/site requirements
comprising the steps of: analyzing feed water to be treated at the
site; establishing a preliminary treatment model; selecting a
sequential treatment regimen from a plurality of available
treatment technologies in accord with said treatment model;
treating feed water on site in accord with said model at a
temporary facility having said plurality of treatment technologies
available thereat; compiling data at said facility related to feed
water treatment and reporting treatment efficacy; when treatment
goals are not met by said preliminary treatment model, establishing
a revised model; and when treatment goals are met by any one of
said models, establishing the proposed commercial plant model.
15. The method of claim 14 wherein the step of establishing the
proposed commercial plant model includes at least any one of
establishing facility design, construction cost estimates and
treatment cost estimates.
16. The method of claim 14 wherein the steps of analyzing feed
water and compiling data at said facility related to feed water
treatment include the step of establishing an automated multi-stage
water quality testing and reporting regime.
17. The method of claim 14 wherein the step of selecting a
sequential treatment regimen from a plurality of available
treatment technologies includes the step of selecting
pre-treatment, water polishing treatment and post-treatment stages
in said regimen.
18. The method of claim 17 wherein said step of selecting a
pre-treatment stage includes the step of selecting from a suite of
selectably actuatable pre-treatment apparatus housed by said
temporary facility.
19. The method of claim 17 wherein said step of selecting a water
polishing treatment stage includes the steps providing at least one
of ion-exchange, nanofiltration and reverse osmosis treatments.
20. The method of claim 17 wherein said step of selecting a
post-treatment stage includes the step of selecting from a suite of
selectably actuatable post-treatment apparatus housed by said
temporary facility.
Description
FIELD OF THE INVENTION
[0001] This invention relates to effluent treatment, and, more
particularly, relates to facilities and methods for modeling and
evaluating particularized water treatment and water treatment
facility requirements, regimens and costs.
BACKGROUND OF THE INVENTION
[0002] Most industrial and municipal processes require water
treatment facilities to treat effluents returned to the
environment. Such facilities typically represent a significant
investment by the business/community, and the performance of the
facility (or failure thereof) can seriously impact ongoing
operations financially and in terms of operational continuity.
[0003] Moreover, not all effluent treatment requires the same
technologies. Industrial effluents (such as is found at coal bed
methane facilities or oil production sites, for example) all have
different particulate, pollutant and/or biomass content inherent to
both the industrial processes as well as the particular water and
soil conditions found at the site. Municipal requirements would
likewise vary depending on desired end-of-pipe quality and use (and
again depending on the feed water present at the site). Given the
expense of full scale water treatment technology deployment, it
would be foolish to plan and build a facility with treatment stages
not needed to address the particular problems to be encountered and
outcomes desired at the particular treatment site. Thus, accurate
site specific evaluation of particular water treatment site
requirements and treatment alternatives in advance of treatment
plant construction is desirable.
[0004] Mobile water treatment facilities have been heretofore
suggested and/or utilized to establish water treatment for
particular circumstances (see, for example, U.S. Pat. Nos.
5,972,216, 6,464,884, 4,383,920 and 5,547,584 and U.S. Patent
Publication No. 2002/0033363). These facilities, however, are
typically end use facilities and employ a predetermined set of
water treatment regimen. Likewise, transportable mechanisms for
previously established water treatment requirements and/or
utilizing particular water treatment mechanisms such as reverse
osmosis have been heretofore suggested and/or utilized (see, for
example, U.S. Pat. Nos. 5,244,579, 5,632,892, 6,120,688, 5,741,416,
and 6,228,255, as well as U.S. Patent Publication No.
2004/0104153). Such mechanisms tend to be limited both in
application and adaptability.
[0005] Therefore, stations and methods directed to evaluating
effluent treatment requirements at proposed treatment sites that
may vary considerably in terms of effluent conditions and desired
treatment outcomes could still be utilized. Moreover, improved
treatment technologies adapted to this and other uses can always be
utilized given the criticality of provision and maintenance of
clean water.
SUMMARY OF THE INVENTION
[0006] This invention provides a mobile station and methods for
diagnosing, modeling and executing design estimates related to site
specific effluent (primarily raw, waste and/or process water)
treatment facility requirements and construction. The station and
methods are adaptable and applicable to a wide variety of
effluents, and establish real time end of pipe information
providing accurate site specific evaluation of particular water
treatment facility operational requirements and treatment
alternatives in advance of treatment plant construction. Thus full
scale plant operation, reliability, size and cost can be reliably
gauged utilizing this invention, thereby reducing financial risk
and improving operational continuity over heretofore known and
utilized water treatment planning and implementation
techniques.
[0007] Utilizing the station and methods of this invention, water
is diagnosed and processed through the station at a particular
treatment site, and data is collected to arrive at a commercial
plant design idealized for the particular water/site requirements.
The station includes both off the shelf components and components
representing other aspects of this invention, and include, for
example, means for methane removal, heavy metal oxidization and
removal, biomass mitigation, coagulation and removal of solids and
colloidal material, membrane treatments, aeration and other
post-treatments.
[0008] The station employs a four stage evaluation and water
treatment regime including initial and ongoing
diagnostics/evaluation, pre-treatment suite, polishing treatment
array (effluent, or water, polishing, as used herein, refers to
primary effluent treatment to a highly developed predetermined
state, and includes membrane and/or ion-exchange treatment
technologies), and post-treatment suite. The station and design
process is quick, cost effective, accurate and relatively simple to
deploy. The methods employ mobile station site set-up, evaluation
and water treatment to establish end-of-pipe information on
operation, reliability, size and cost for deployment of a fully
functional permanent treatment plant for the site.
[0009] The mobile station includes a mobile platform having power
intake, effluent intake and fluid outflow facilities. A first suite
of selectably actuatable effluent pre-treatment apparatus is housed
by the mobile platform and connected with the effluent intake
facility. A second suite of selectably actuatable effluent
pre-treatment apparatus is operationally associated with the first
suite of pre-treatment apparatus. An effluent polishing treatment
array housed by the mobile platform is connected with the suite of
pre-treatment apparatus, and a suite of selectably actuatable
effluent post-treatment apparatus is connected with the polishing
treatment array and the fluid outflow facility of the mobile
platform.
[0010] Controls are connectable with the power intake facility and
various components housed at the mobile platform for process
control, testing and data accumulation, and to report a site
specific effluent treatment regimen and effluent treatment facility
model.
[0011] The methods of this invention aid in the diagnosing and
modeling of site specific water treatment facility requirements to
arrive at a proposed commercial plant model idealized for the
particular water/site requirements. The methods include the steps
of analyzing feed water to be treated at the site and establishing
a preliminary treatment model. A sequential treatment regimen is
selected from a plurality of available treatment technologies and
the feed water is then treated on site at a temporary facility
having the plurality of treatment technologies available thereat in
accord with the model.
[0012] Data is compiled at the facility related to feed water
treatment and treatment efficacy is reported. When treatment goals
are not met by the preliminary treatment model, a revised treatment
model is established. When treatment goals are met by any one of
the models, the proposed commercial plant model is established.
[0013] It is therefore an object of this invention to provide
mobile stations and methods for diagnosing and modeling site
specific effluent treatment facility requirements.
[0014] It is another object of this invention to provide mobile
stations and methods for diagnosing, modeling and executing design
estimates related to site specific raw, waste or process water
treatment facility requirements and construction.
[0015] It is another object of this invention to provide effluent
treatment stations and methods that are adaptable and applicable to
a wide variety of effluents, and provide accurate site specific
evaluation of particular water treatment site requirements and
treatment alternatives in advance of treatment plant
construction.
[0016] It is still another object of this invention to provide
mobile facilities and methods for diagnosing and processing water
at a particular treatment site, and collecting data therefrom to
arrive at a proposed commercial plant design idealized for the
particular water/site requirements.
[0017] It is yet another object of this invention to provide a
station for diagnosing and modeling site specific effluent
treatment facility requirements that employs a four stage
evaluation and water treatment regime including
diagnostics/evaluation, pre-treatment suite, polishing treatment
array, and post-treatment suite.
[0018] It is another object of this invention to provide a mobile
station and methods for diagnosing and modeling site specific
effluent treatment facility requirements wherein the design station
and processes are quick, cost effective, accurate and relatively
simple to deploy.
[0019] It is still another object of this invention to provide a
mobile station for diagnosing and modeling site specific effluent
treatment facility requirements including a mobile platform having
power intake, effluent intake and fluid outflow facilities, a first
suite of selectably actuatable effluent pre-treatment apparatus
housed by the mobile platform and connected with the effluent
intake facility of the mobile platform, an effluent polishing
treatment array housed by the mobile platform and connected with
the suite of pre-treatment apparatus, a suite of selectably
actuatable effluent post-treatment apparatus housed by the mobile
platform and connected with the polishing treatment array and the
fluid outflow facility of the mobile platform, and control means
connectable with the power intake facility of the mobile platform
for process control and data accumulation to thereby optimize a
site specific effluent treatment regimen and establish a site
specific effluent treatment facility model.
[0020] It is yet another object of this invention to provide a
temporary facility for water quality analysis, treatment modeling,
selective contaminated water processing, and data accumulation at a
particular treatment site to arrive at a proposed commercial water
treatment plant model idealized for the particular water/site
requirements, the facility including a first suite of selectably
actuatable effluent pre-treatment apparatus connected with a feed
water intake, a second suite of selectably actuatable effluent
pre-treatment apparatus operationally associated with the first
suite of pre-treatment apparatus, a water polishing treatment
array, including at least one of a membrane treatment array and an
ion-exchange treatment array, connected to receive feed water after
selected processing at the first and second suites of pre-treatment
apparatus, a suite of selectably actuatable post-treatment
apparatus connected to receive water processed through the water
polishing treatment array and providing therefrom a treated water
outflow, and control means connectable with the first and second
suites of pre-treatment apparatus, the polishing treatment array
and the suite of post treatment apparatus for process control and
data accumulation to thereby optimize a site specific water
treatment regimen and establish the site specific proposed
commercial water treatment plant model.
[0021] It is yet another object of this invention to provide a
method for diagnosing and modeling site specific water treatment
facility requirements to arrive at a proposed commercial plant
model idealized for the particular water/site requirements, the
method including the steps of analyzing feed water to be treated at
the site, establishing a preliminary treatment model, selecting a
sequential treatment regimen from a plurality of available
treatment technologies in accord with the treatment model, treating
feed water on site in accord with the model at a temporary facility
having the plurality of treatment technologies available thereat,
compiling data at the facility related to feed water treatment and
reporting treatment efficacy, when treatment goals are not met by
the preliminary treatment model, establishing a revised model, and
when treatment goals are met by any one of the models, establishing
the proposed commercial plant model.
[0022] With these and other objects in view, which will become
apparent to one skilled in the art as the description proceeds,
this invention resides in the novel construction, combination, and
arrangement of parts and methods substantially as hereinafter
described, and more particularly defined by the appended claims, it
being understood that changes in the precise embodiment of the
herein disclosed invention are meant to be included as come within
the scope of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The accompanying drawings illustrate a complete embodiment
of the invention according to the best mode so far devised for the
practical application of the principles thereof, and in which:
[0024] FIG. 1 is a perspective view showing the exterior of the
mobile effluent evaluation and treatment station of this
invention;
[0025] FIG. 2 is a diagrammatic floor plan of the station of FIG.
1;
[0026] FIG. 3 is an alternative diagrammatic floor plan of the
station of this invention showing a different configuration of
treatment options;
[0027] FIG. 4 is a block diagram illustrating the phased functions
of the station of FIG. 1;
[0028] FIG. 5 is a flow chart showing overall process controls
utilized by the station of FIG. 1;
[0029] FIGS. 6a through 6d are flow charts illustrating treatment
option selection and implementation in the station of FIG. 1;
[0030] FIG. 7 is a diagram illustrating pre-treatment
sampling/testing locations for real time fluid testing and
reporting to program control;
[0031] FIG. 8 is a diagram illustrating other pre-treatment
sampling/testing locations for real time fluid testing and
reporting;
[0032] FIG. 9 is a diagram illustrating primary (effluent
polishing) treatment sampling/testing locations for real time fluid
testing and reporting;
[0033] FIG. 10 is a diagram illustrating post-treatment
sampling/testing locations for real time fluid testing and
reporting;
[0034] FIG. 11 is a block diagram illustrating a portion of the
control program;
[0035] FIG. 12 is a block diagram illustrating process calculations
output related to the portion of the control program shown in FIG.
11;
[0036] FIG. 13 is a diagram primarily illustrating portions of the
first pre-treatment suite of the station of this invention;
[0037] FIG. 14 is a sectional illustration of a gas liberator used
in the first pre-treatment suite;
[0038] FIG. 15 is a diagram illustrating a second embodiment of one
of the components utilized in the first pre-treatment suite of the
station of this invention;
[0039] FIG. 16 is a diagram illustrating a first embodiment of a
membrane aeration apparatus used in the second pre-treatment suite
of the station of this invention;
[0040] FIG. 17 is a diagram illustrating a second embodiment of a
membrane aeration apparatus used in the second pre-treatment
suite;
[0041] FIG. 18 is a diagram illustrating a third embodiment of a
membrane aeration apparatus used in the second pre-treatment
suite;
[0042] FIG. 19 is a diagram illustrating a fourth embodiment of a
membrane aeration apparatus used in the second pre-treatment
suite;
[0043] FIG. 20 is a sectional illustration of a membrane aeration
apparatus of the second pre-treatment suite;
[0044] FIG. 21 is a diagram illustrating other components utilized
in the second pre-treatment suite;
[0045] FIG. 22 is a sectional illustration of an electrocoagulation
unit utilizable in the second pre-treatment suite;
[0046] FIG. 23 is a partial sectional illustration of the housing
of the unit of FIG. 22;
[0047] FIG. 24 is a diagram illustrating a first membrane
technology of this invention utilizable in steps directed to the
primary, polishing treatment of effluents;
[0048] FIG. 25 is a diagram illustrating a second membrane
technology of this invention utilizable in steps directed to the
primary treatment of effluents;
[0049] FIGS. 26a and 26b are illustrations of coil structures
utilizable in the technology of FIGS. 24 and 25;
[0050] FIG. 27 is a detailed view illustrating coil cooling
utilizable in the technology of FIGS. 24 through 26;
[0051] FIG. 28 is a diagram illustrating apparatus for internal
concentration polarization control in the technology of FIGS. 24
through 26;
[0052] FIG. 29 is a diagram illustrating one membrane deployment
option utilizable in the primary treatment steps in the station of
this invention;
[0053] FIG. 30 is a sectional illustration of a crossflow pump of
this invention utilized in various membrane separation
technology;
[0054] FIG. 31 is a sectional illustration of an improved degasser
column used with the membrane systems of this invention;
[0055] FIG. 32 is a flow distributor and discharge equalizer
deployed, for example, with the membrane systems of this
invention;
[0056] FIGS. 33a and 33b are diagrams illustrating a high frequency
oscillating membrane system utilizable in primary treatment steps
in the station of this invention;
[0057] FIG. 34 is a sectional diagram illustrating a second
embodiment of the high frequency oscillating membrane system;
[0058] FIG. 35 is a partial sectional illustration of the
oscillating membrane system of FIG. 34;
[0059] FIG. 36 is a detailed sectional illustration of the upper
part of the oscillating membrane system of FIG. 35;
[0060] FIG. 37 is a detailed sectional illustration of the lower
part of the oscillating membrane system of FIG. 35;
[0061] FIG. 38 is an illustration showing function of the spirally
wound membrane elements of the oscillating membrane system of FIG.
35 (also employable in other oscillating systems shown herein);
[0062] FIG. 39 is a diagram illustrating an alternative deployment
of the oscillating membrane system of FIG. 35;
[0063] FIG. 40 is a sectional illustration of a vibratory seal
arrangement for the oscillating membrane system of FIGS. 35 and
36;
[0064] FIG. 41 is a sectional illustration of a high shear
embodiment of the oscillating membrane system of FIGS. 34 through
39;
[0065] FIG. 42 is a sectional illustration of a draw-off utilizable
in the high shear embodiment of FIG. 41;
[0066] FIG. 43 is a diagram illustrating an alternative oscillatory
fluid column crossflow membrane separation system utilizable in
primary treatment steps at the station of this invention;
[0067] FIG. 44 is a diagram illustrating a vibratory retentate
membrane separation system utilizable in primary treatment steps at
the station of this invention;
[0068] FIG. 45 is a diagram illustrating another alternative
oscillating retentate membrane separation system utilizable in
primary treatment steps at the station of this invention;
[0069] FIG. 46 is a diagram illustrating the apparatus of the
post-treatment suite of the station in combination with a
biomonitoring aquarium;
[0070] FIG. 47 is a diagram illustrating one element of the
post-treatment suite of the station of this invention;
[0071] FIG. 48 is a flow diagram illustrating the post-treatment
suite of FIG. 46 in combination with output drain and disposal
facilities;
[0072] FIG. 49 is a diagram illustrating indicative treatment
control and platform power wiring;
[0073] FIGS. 50a through 50c show a first embodiment of a spacer
arrangement for use in axial vibratory membrane separation
modules;
[0074] FIGS. 51a and 51b illustrate a second embodiment of the
spacer arrangement for axial vibratory membrane separation
modules;
[0075] FIGS. 52a through 52c show a third embodiment of the spacer
technology for axial vibratory membrane separation modules;
[0076] FIG. 53 shows a fourth embodiment of the spacer technology
for axial vibratory membrane separation modules;
[0077] FIG. 54 is a side sectional view of a rotating biological
contactor treatment assembly;
[0078] FIG. 55 is a second sectional side view of the assembly of
FIG. 54; and
[0079] FIGS. 56a through 56c are illustrations showing various
embodiments of conveyor contactor fabrics utilizable with the
assembly of FIG. 54.
DESCRIPTION OF THE INVENTION
[0080] FIG. 1 shows the trailerized mobile diagnostic and treatment
modeling pilot station 101 of this invention.
[0081] The station is housed in compact tractor towed trailer 103
(for example 8' by 48'). The treatment facilities occupy an area of
approximately 8' by 30' in the trailer (240 square feet), the
remaining 18 feet utilizable for other functions such as a
lab/office and shop space. The height of the station is
approximately 8 feet. Trailer 103 includes power intake and
communications access panels 105 and 107, respectively, vacuum
exhaust 109, and effluent connection ports 111, 113 and 115
(effluent feed intake, treated fluid outflow and recirculated
return, respectively). Primary and emergency access structures 117
and 119, respectively, provide for access to the station.
[0082] Mobile station 101 is configured for diagnosing and modeling
site specific effluent treatment facility requirements, and is thus
primarily for use as a temporary facility for water quality
analysis, treatment modeling, selective contaminated water
processing. Data accumulated at a particular treatment site is then
utilized to arrive at a proposed commercial water treatment plant
model idealized for the particular water/site requirements.
[0083] Station 101 incorporates 19 major treatment stages, or
steps, as discussed hereinafter, as well as diagnostic, testing and
control equipment. A field generator, where required (see FIGS. 2
and 3, generator facility 121), must provide for a maximum load of
220 amps. The stations normal load is 165 amps, 230 VAC. The
minimum generator power requirement is 60 kW.
[0084] The 19 major treatment stages, or steps, at mobile pilot
station 101 represent all technologies which can be practically
applied in a given effluent treatment environment (for example,
CBM-produced water treatment) in order to allow selective
combination of treatment options to provide real time operating
fluid treatment diagnosis subject to local process control. In this
manner, and utilizing programs and methods of this invention,
optimized site specific water treatment regimes and plant
performance can be gauged at the site, with upscaling of parameters
provided for full-size commercial plant design modeling and
associated design and/or treatment cost estimate development (on
site and/or remotely by communication link).
[0085] Turning to FIGS. 2 and 3, there are four major phases of
planning and treatment in station 101 that together enable
establishment of a full scale plant design. These phases are
diagnostic and evaluative (both initial and ongoing) 201,
centralized control managing testing, processes and data
accumulation, at least one pre-treatment suite (preferably two
suites) of water treatment apparatus 203, a polishing treatment
array (primary water treatment phase) which may include
ion-exchange and/or membrane treatment systems 205, and a
post-treatment suite of water treatment apparatus 207.
[0086] In addition, station 101 includes an isolation transformer
209, master control panel 211 (housing various switching and the
like for motor controlled valves, motors, pumps and other units),
power control switch panel 213, membrane testing station and work
bench 215 and mechanical services and storage area 217.
[0087] The trailerized station is typically sited inside a lined
pit and is leveled utilizing blocks and/or support legs 123 (FIG.
1). The lined pit provides positive containment for spilled fluids
in case of catastrophic failure and includes a dewatering pump.
Station 101 typically is operated in a semi-wet environment, and
free running fluids may accumulate from sources such as sampling
points, fluid testing locales, equipment change locations, repair,
preventive maintenance and cleaning operations, operational
condensation and the like. In many cases, such fluids must be
contained. It is therefore best when siting station 101 to also
locate a spill pan beneath station 101.
[0088] Primary fluid transfer is provided and controlled by two
electrical solenoid valves for feed and return fluids, each having
manual override capability. The solenoid valves are of the normally
closed category, so that, in case an event requiring emergency
shutdown occurs, no fluid is transferred into or out from station
101.
[0089] FIG. 4 shows the interrelationship of the 19 treatment steps
contained by station 101 (location of some of which may also be
seen in FIGS. 2 or 3). The option numbers located at three-way
valves 401 refer to automated or override manual flow control
options for different treatment regimes (discussed further with
reference to FIG. 6a). Stage 403 (step 1) is a dual strainer
receiving feed effluent and removing particulates down to about 500
.mu.m (for example, the model 120 dual strainer produced by Plenty
Products, Inc.). Stage 405 (step 2) provides oil separation from
the feed flow utilizing a separator (for example, a Highland Tank
& Mfg. Co. R-HTC Oil/Water Separator with Petro-Screen and
parallel corrugated plate coalescers). Stage 407 (step 3) is an
automatic backflush filter providing particle removal down to the
100 .mu.m range or better (a TEKLEEN self cleaning bell filter
setup with GB6 electric controller by Automatic Filters, Inc., or
similar filter setups by Amiad Filtration Systems, could be
utilized for example).
[0090] Stage 409 (step 4) provides inline direct feed effluent
(water) heating. Feed water heating is required in many treatment
settings due to seasonal operations, and further benefits many
downpipe treatment options by breaking feed water alkalinity,
enhancing CH.sub.4 gas removal, ensuring proper membrane (where
present) permeate flux for an overall constant permeate flow yield,
and the like. Either of two types of inline heating systems may be
utilized, as more fully detailed below.
[0091] Stage 411 (step 5) is a first suite of pre-treatment
apparatus including eight apparatus (all eight are preferred, but
fewer could be provided in some applications). These apparatus
provide, as more fully detailed below, on-line diffusive effect
(ODE) membrane aeration, fluid density reduction, modified vacuum
tower or cascade series waterfall degassing, air stone degassing,
modified venturi gas evacuation, fine filtration, lamella plate
clarification, and sludge chamber concentration.
[0092] Stage 413 (step 6) is a second suite of pre-treatment
apparatus including ten apparatus (all ten are preferred, but fewer
could be provided in some applications). As more fully detailed
herein below, the ten apparatus provide pH adjustment (via
injection pump 302 of FIGS. 2 through 4), chemical dosing (via
injection pump 304 of FIGS. 2 through 4), ODE/IDI (inline diffusive
ionization) membrane aeration, ionized air/gas treatment,
electrocoagulation, dissolved air/gas flotation, vacuum introduced
cyclone separation, vacuum degassing, lamella plate clarification,
and sludge chamber concentration.
[0093] Stage 415 (step 7) provides a bag filter and/or belt filter
assembly (for example, fabric filtration systems sold by SERFILCO)
for filtration down to about the 1 .mu.m range. Stage 417 (step 8)
is a homogenizing and buffer tank with pH adjustment and chemical
dosing (at injection pumps 306 and 308, respectively). Stage 419
(step 9) is the first of the polishing treatment array (stages 419
through 433, steps 9 through 16), and may include any of several
membrane treatment apparatus (as shown in FIG. 2) in accord with
this invention as more fully detailed hereinafter providing
nanofiltration, and/or known ion-exchange treatment technology (as
shown in FIG. 3 at 310). Stage 419, as is apparent, is an option
for up-concentrating effluent to increase overall flow yield.
[0094] Stage 421 (step 10) provides antifouling and antiscaling
chemical treatment to prevent fouling and scaling of membranes by
keeping low molecular weight components in solution (foremost of
which are divalent and multivalent cations). Known variable speed
tubing pumps could be utilized for insertion. Stage 423 (step 11)
provides filtration for removal of low molecular weight components
(Al, Fe, Mg and Mn, for example) and/or colloidals utilizing
membrane treatment nanofiltration (FIG. 2) and/or ion-exchange
treatment (FIG. 3). Stage 425 (step 12) provides a buffer tank for
step 14 for process flow control (for example a Snyder horizontal
leg tank by Harrington). Stage 427 (step 13) provides antiscaling
chemical treatment addressing monovalent and a few divalent cations
and anions (Ba, Ca, Na, Sr, CO.sub.3F, HCO.sub.3, and SO.sub.4 for
example). Again, known variable speed tubing pumps could be
utilized for insertion.
[0095] Stage 429 (step 14) addresses removal of low molecular
weight components (salts, for example) utilizing reverse osmosis
membrane treatment (FIG. 2) and/or ion-exchange treatment (FIG. 3).
Stage 431 (step 15) is a high pressure buffer tank providing flow
control for step 9 and/or 16. Stage 433 (step 16) provides
up-concentration of concentrate flow from stage 429 to further
increase flow yield, and may utilize reverse osmosis membrane
treatment (FIG. 2), ion-exchange treatment (FIG. 3) and/or high
efficiency electrodialysis technology (for example, a HEED assembly
by EET Corporation), a hybrid process including both
electrodialysis and reverse osmosis approaches.
[0096] Stage 435 (step 17) is a suite of four post-treatment
apparatus as more fully detailed herein below, and including
activated carbon filtration for gas absorption (Ametic filter
chambers by Harrington, for example), sodium absorption ratio
compensation, utilizing a dolomite filter for example, UV treatment
(for example, an SP or SL series unit from Aquafine Corporation),
and membrane aeration for O.sub.2 saturation (preferably utilizing
an ODE system in accord with yet another aspect of this
invention).
[0097] Stage 437 (step 18) provides bio-monitoring utilizing an 10
gallon aquarium with the operating volume passing through either a
sterilizer or other aquarium device to prevent in situ
bio-contamination from waste and nutrients. The sterilizer or other
device must match the maximum produced permeate flow of at the rate
of approximately one gallon per minute for real time
bio-monitoring. Since the sterilized water from station 101 is
always being mixed with unsterilized water, it is not possible to
completely purify it, but a sterilized percentage exceeding 99.9%
is acceptable for the bio-monitoring step sensitivity. Stage 439
(step 19) conventionally provides waste collection and purified
feed return.
[0098] Regarding the ion-exchange treatment alternative at stages
419, 423, 429, and 433 (steps 9, 11, 14 and 16), this process is a
well known water treatment process for removing ions from solution
by exchanging cations or anions between the dissolved phase and
counter ions on a matrix such as organic zeolite, in which
Ca.sub.2.sup.+ ions in solution displace Na.sup.+ ions in the
zeolite, montmorillonite (a colloidal bentonite clay) or
synthetically produced organic resins, for example.
[0099] An organic ion exchange resin is composed of high
molecular-weight polyelectrolytes that can exchange their mobile
ions for ions of similar charge from the surrounding medium. Each
resin has a distinct number of mobile sites that set the maximum
quantity of exchanges per unit of resin. Ion exchange reactions are
stoichiometric and reversible.
[0100] Commercially available ion-exchange treatment technology can
be utilized alone as an alternative to the hereinafter detailed
membrane treatment technology or may supplement specific membrane
technology. The implementation of ion-exchange technology depends
on the specific application and project economics (the less complex
and labor-intensive state of the art ion exchange technology may be
used as a single polishing step instead of membrane treatment where
cost is a factor and desired treatment outcomes warrant the
tradeoff).
[0101] In some settings, primarily depending on the intended use of
the purified water, complete deionization (replacement of all
cations by the hydrogen ion as well as replacement of all anions by
the hydroxide ion) may be required. In such case, commercial
cation- and anion-exchange technology will be employed as a
polishing treatment step alone or in addition to membrane treatment
(again depending on the end-of-pipe outcomes desired). For example,
a feed water with total dissolved solids of less than about 500
mg/L is ideally suited for ion exchange technology in combination
with reverse osmosis membrane treatment. In other words, after
membrane treatment at step 14 (429), the produced permeate is fed
into a strongly acidic cation exchanger followed by a strongly
basic anion exchanger (substituting for both steps 15 and 16). Such
systems are commercially available from KINETICO, REMCO ENGINEERING
and others.
[0102] Turning now to FIG. 5 summarily illustrating the method of
operation of station 101 under process control, after
initialization of the system the effluent to be treated is
subjected to testing along a variety of parameters discussed
hereinafter. A low/high limit data base is utilized together with
selected treatment outcomes (parameters) to establish a treatment
model. If the model is acceptable, treatment stages (as discussed
above) are selected and implemented at station 101. If the model is
unacceptable for any reason, the process may be halted or treatment
parameters altered and effluent testing conducted accordingly
(retesting may be omitted in most cases unless new parameters
require different testing combinations).
[0103] Ongoing testing at various junctures in the staged
processing of feed water is input into the system to gauge
effectiveness of effluent treatment stages selected. If treatment
reporting is unfavorable, the treatment model may be revised in
accord with testing, or treatment parameters may be changed and the
process restarted. If treatment reporting is favorable, the
selected model and stages are upscaled to commercial plant
proportions, and plant design, plant costs and/or treatment cost
outputs are reported. If the report is acceptable, it is finalized.
If not acceptable (for economic or other reasons), model revision
or parameter changes may be undertaken.
[0104] FIGS. 6(a through d) further illustrate treatment option
selection and implementation in station 101. The process options
(Opt. 1 though 10) correspond to the same options in FIG. 4 made by
operation of the various valves 401. In FIG. 6a, "AC" refers to
activated carbon venting. After straining, the first control option
allows omission of oil separation step 405. Option 2 allows
automatic back flush filter 407 to be omitted from the treatment
chain. Option 3 directs treatment flow to either pre-treatment
suite 411 or heater 409. Option 4 allows omission of pre-treatment
suite 413, while valve option 5 directs flow selectively to
treatment apparatus 419. Option 6 allows omission of chemical
dosing step 421, treatment step 423 and buffer tank 425 in the
processing chain. Option 7 selects either upconcentrating of
concentrate from treatment step 423 at treatment 419 or omission
thereof, and option 8 selects whether or not to upconcentrate
concentrate from treatment step 429 at steps 431 and 433. Option 9
allows omission of post-treatment suite 435 and biomonitoring 437,
while option 10 selects for omission of only the biomonitoring
step.
[0105] In FIG. 6b and 6c, control functions of the plurality of
treatment apparatus of first and second pre-treatment suite stages
411 and 413 are illustrated. Each choice allows omission of the
immediately following treatment apparatus step and choice. FIG. 6d
illustrates that each of the treatment apparatus options of
post-treatment suite stage 435 may be bypassed (as may the suite
itself).
[0106] FIG. 7 illustrates elements of pre-treatment suite 411 and
testing nodes (in line sampling stations for performing process
treatment testing and data output to computer control) utilized for
process and treated effluence analysis automation. FIGS. 8, 9 and
10 show similar features in pre-treatment suite 413, treatment
array 205 and post-treatment suite 435, respectively. In FIG. 7,
seven of the eight pretreatment apparatus of suite 411 are shown.
These include ODE membrane aeration apparatus 701, deironator 702
(for fluid density reduction), modified vacuum tower degasification
apparatus 703, air stone degassing apparatus 704, venturi gas
evacuation apparatus 705, fine filtration apparatus 706 (an edge
filter arrangement), and lamella plate clarification apparatus 707
(including primary and secondary tanks each having a sludge chamber
concentration portion 708 therein). In addition seven test nodes
711 through 723 are shown.
[0107] FIG. 8 shows nine of the ten apparatus of pre-treatment
suite 413 (the ionized air/gas treatment is not identified). These
include pH and chemical dosing apparatus 801 and 802, respectively,
ODE/IDI membrane aeration apparatus 803, electrocoagulation
apparatus 805, dissolved air/gas flotation 806, vacuum introduced
cyclone separation apparatus 807, vacuum degassing 808, lamella
plate clarification 809 and sludge concentration output 810.
Additionally, eight testing nodes 811 through 825 are shown.
[0108] The primary function of the Pre-Treatment suite 413 is the
removal or significant reduction (exceeding 90%) of colloidal
matter with total suspended solids, such as polysaccharides or
other slimy matter, less than about 75 nm. In addition, removal or
significant reduction (by 80 to 90%) of fats, grease, oils and
emulsions, and heavy metals (such as barium, strontium and others)
by 60 to 99% is achievable. Finally, removal of entrained and
produced gas by vacuum down to residual levels is achieved.
[0109] FIG. 9 shows the array 205 of FIG. 2 (utilizing a membrane
treatment array). Eight testing nodes 901 through 915 are also
illustrated. FIG. 10 shows all four apparatus included in
post-treatment suite 435. These include activated carbon filter
1001, sodium absorption ratio compensation apparatus 1003, UV
disinfection apparatus 1005 and membrane aeration apparatus 1007.
Nine testing nodes 1011 through 1027 are also shown.
[0110] There are nine different testing instruments utilized at the
32 testing nodes in the suites 411, 413, and 435 and treatment
array 205. These include instruments for measuring: total organic
carbon (TOC, at nodes 711 and 1023); turbidity (at nodes 713 and
1027); pH (at nodes 811, 817, 825, 901, 1011, and 1015); dissolved
oxygen (at nodes 1013 and 1025); liquid flow (at nodes 719, 815,
821, 907, 911, 913, and 1017); gas flow (at node 723); conductivity
(at nodes 715, 823, 903, 915, and 1019); pressure (at nodes 717,
721, 813, 819, 905 and 909); and CH.sub.4 (at node 1021).
Additional testing nodes (as well as testing instruments of
different kinds) could be applied with this system and programmed
accordingly, as may be appreciated.
[0111] Instrument drivers and data storage are housed and channeled
at a standard PC or other computer, on LAN (Local Area Network
covering the whole station 101). A standard Ethernet Hub or Switch
is utilized as is an Internet access (hard wire or wireless) for
remote monitoring and operation where required.
[0112] The various measuring instruments employed are relatively
standard devices. Raw feed water into station 101 will often
contain high concentrations of total organic carbon ("TOC")
contamination, also known as the total oxidizable carbon. If left
unchecked, said TOC contamination may cause fouling in reverse
osmosis membranes and tend to support biological activity in the
whole water treatment facility. TOC measurement is used
industry-wide as the standard process for determining organic
carbon contamination and to measure the effect of the employed TOC
reduction process. Real time effect values of the TOC reduction
processes utilized in station 101 is indicated, monitored,
registered, stored (and recalled) as nonvolatile memory for either
process evaluation or plant sizing data. To obtain said TOC
reduction process effect values, two separate TOC instruments are
employed, the first measuring incoming TOC and the second measuring
the outgoing TOC whereby the dimensionless TOC reduction process
effect values are obtained.
[0113] The instruments for measuring organic contaminants utilize
chemical or UV oxidizing of the contaminants to create carbon
dioxide. The conductivity increase or the change in the reading of
an infrared detector are then measured to yield a measure of the
amount of carbon bound in entrained organic material (reported in
units of ppm as carbon). Typical TOC measuring analyzers are made
by SHIMADZU, HACH and others. Preferred water TOC level measurement
should be capable of a range from a minimum of 10 ppm to a maximum
of 150 ppm.
[0114] Turbidity refers to the suspension of fine colloidal
particles that do not readily settle out of solution and that can
result in water cloudiness. Turbidity is measured by a Nepholometer
measuring the relative amount of light able to pass through a
solution, and is reported as NTU (Nepholometric Turbidity Units).
Turbidity measurement is used as a substitute for gravimetric
solids measurement in the monitoring and controlling of various
water treatment processes. In station 101, this measurement serves
as an on-line indicator for the rate of reverse osmosis membrane
fouling. Typical reverse osmosis elements list a maximum of 1.0 NTU
for the feed water. As turbidity readings exceed 1.0 they are
indicative of a greater tendency for membrane fouling. Optionally,
turbidity measurements can also be used as an analytical tool to
evaluate the changing abilities of different pre-treatment steps to
remove potential membrane foulants. Instruments made by HACH (GLI
Accu 4 Low Range Process Turbidimeter) are preferred.
[0115] The pH of water is a means of expressing its acidity or
basicity. The measurement of pH is a method of expressing hydrogen
ion concentration logarithmically with the pH value being the
negative logarithm (base 10) of the hydrogen ion concentration.
Measurement of pH is important to water analysis, as the pH will
dramatically affect the solubility of a number of slight soluble
salts present in the various feed waters. pH is important in
defining the alkalinity equilibrium levels of carbon dioxide,
bicarbonate, carbonate and hydroxide ions. The concentrate pH is
typically higher than the feed due to the higher concentration of
bicarbonate/carbonate ions relative to the concentration of carbon
dioxide.
[0116] Furthermore, the pH of a cleaning solution is an indicator
of one of the most important mechanisms available for cleaning most
membrane foulants and scale. Acidic solutions are effective at
removing scale. The removal of foulants that originated from
suspended solids or biological activity is performed with alkaline
solution. Its high concentration of negatively charged hydroxide
ions can break up and solubilize organic fats and oil that may be
present. It can also disperse remaining solids since many of these
tend to also have negative charge characteristics. Lowering the
feed pH with acid results in a lower LSI (Langlier Saturation
Index) value, which reduces the scaling potential for calcium
carbonate. Feed and concentrate (reject) pH can also affect the
solubility and fouling potential of silica, aluminum, organics and
oil. Variations in feed pH can also affect the rejection of ions.
For example, fluoride, boron and silica rejection are lower when
the pH becomes more acidic.
[0117] A typical pH measurement system always consists of four
parts: a pH sensing electrode; an amplifier that translates the
signal (4 to 20 mA) into something the controller unit can read; a
reference electrode; and on-line implementation. Each part of the
system plays a critical role in the on-line measurement process.
Any reputable brand of on-line pH indication, registration and
controlling system could be utilized herein, for example the
systems provided by SIGNET Analytical Instruments.
[0118] Dissolved oxygen (DO) refers to the amount of oxygen in a
unit volume of water (mg/L or ppm). Finished processed water
discharged as augmentation water into a stream or river needs
oxygenation to sustain aquatic life. It is generally considered
that DO levels of at least 4-5 ppm are sufficient for most aquatic
life, however good waters average about 9.0 ppm. The total
dissolved gaseous oxygen (O.sub.2) concentration in water should
not exceed 110%. Concentrations above this level can be harmful to
aquatic life forms.
[0119] Station 101 employs an on-line dissolved oxygen measuring,
monitoring and controlling system for providing real-time
operational information as well as permanent records for
administrative agency compliance. The DO system consists of a
preamplified DO sensor. Its active electronics, located directly in
the sensor, process the sensitive sensor signal on-site. A control
signal regulates compressed air flow supply through various aerator
membranes at station 101, whereas a scaled signal in either mg/L or
ppm units is displayed on the control monitor. A potentiostatic
three-electrode system for measuring DO is preferred in this
application (for example, systems by WTW).
[0120] Since the liquid in all standard process phases is
conductive in ranges exceeding 5 .mu.S/cm, this system uses only
electromagnetic flowmeters for in-line liquid flow indication,
monitoring and registration. These flowmeters are very accurate,
the pressure drop across the meter being the same as it is through
an equivalent length of pipe because there are no moving parts or
obstruction to flow. The instrument can be attached directly to a
flow tube or mounted remotely and connected to the tube by a
shielded cable. Any reputable electromagnetic flow indication,
monitoring and registration system can be used (for instance, the
FMG-401H flowmeter provided by OMEGA).
[0121] Traditional thermal-type mass flowmeters for air/gas
measurements are utilized in station 101 (for example, an SRL
inline style thermal mass flow indication, monitoring and
registration system by SAGE METERING, INC.)
[0122] Conductivity is a measurement of the ability of water to
transmit electricity due to the presence of dissolved ions.
Conductivity measurement is a method for determining the level of
ions in a water, but does not identify the ion. Because the
electrical current is transported by the ions in solution, the
conductivity increases as the concentration of ions increases, thus
conductivity increases as water dissolves ionic species. The basic
unit of conductivity is the siemens (S). Since cell geometry
affects conductivity values, standardized measurements are
expressed in specific conductivity units (S/cm) to compensate for
variations in electrode dimensions.
[0123] Conductivity measurements are used to obtain the data
necessary to determine TDS (Total Dissolved Solids) values.
Furthermore, the in-line conductivity measurements are utilized in
the operational software with a conversion factor to convert water
conductivity into total dissolved salts. This data can then be used
in software to calculate a present salt rejection based on
conductivity in the membrane processes. There is generally a direct
relationship between conductivity and the concentration of ions in
a solution. Any reputable conductivity indication, monitoring and
registration system can be utilized (for example, CDCN-80 systems
by OMEGA).
[0124] Pressure is the driving force in mobile test station 101.
The software system for monitoring and data logging requires
pressure sensors (transmitters are preferred) with current outputs
of 4 to 20 mA. A pressure transmitter is simply a pressure
transducer with some extra electronics to transmit the signal. Uses
include monitoring the pressure drop in a membrane system for
monitoring and energy requirement calculations. Pressure
indication, monitoring and registration systems provided by OMEGA'S
PXO1C1 series provide 4 to 20 mA output, very high accuracy
pressure transmitters with 1/4 NPT pressure connections.
[0125] CH.sub.4 measuring is preferably conducted with a Method 25
GC system by GenTech Scientific, Inc. This on-line instrument
includes an FID detector, built in air compressor and backflush gas
sampling valve for determination of methane/non-methane
hydrocarbons.
[0126] Turning now to FIGS. 11 and 12, the program control and
program process calculations are described. In general, while not
shown, to use the program the program directory must be accessed
and the water system program file opened. The program starts with a
main screen having selectable subdirectories for the four sections
411, 413, 205 and 435 corresponding to various treatment options
therein. The structure is as shown in FIG. 11. By selecting a
desired subdirectory at the main screen control screens related to
pre-treatment suites 411 or 413, polishing array 205 or
post-treatment suite 435 can be viewed and operated. Real time
instrument generated and/or manual data input or readout can be
obtained at the different screens.
[0127] On a selected subdirectory screen values can be changed in
the data fields. A detailed help file is available at the main
screen or subdirectory screens. Once all data fields are filled, a
"CALCULATION" selection at the main screen is enabled. Selecting
the CALCULATION operation leads to the outputs identified in FIG.
12. A report screen of the calculated results together with
upscaling reports follows.
[0128] Detail regarding the various apparatus in station 101 for
performing steps 1 through 19 (stages 403 through 439 in FIGS. 4
and 6a) follows hereinbelow, with greater attention paid the
numerous additional aspects of this invention as shown in FIGS. 13
through 50.
[0129] At stage 409, either of two types of inline heating systems
may be utilized. Commercially available inline electric water
heaters set up for continuous operation may be utilized. These
heater, due to limited heat transfer capability, must be
supplemented by a gas-fired tank heating system in an outside
supply tank.
[0130] Thus, the preferred method of water heating in the station
of this invention, in accord with an additional aspect of this
invention, is an inline steam heating system for direct raw feed
water heating which either does not require a gas-fired heater in
the outside tank system or requires considerably less heating
energy from the outside tank heater as shown in FIG. 13. This
inline direct feed water steam heating system works in a steam
diffusion mode where pressurized injected steam diffuses from an
outer jacket 1311 through a tubular porous sintered ceramic, glass,
stainless steel PVDF or PTFE membrane body 1313 into the feed
water, which flows inside of the membrane. Also located inside of
the membrane is a stainless steel static inline mixing element 1315
to provide a rapid homogenizing effect, whereby the mixing energy
is derived from the mixers pressure drop.
[0131] The heating system is comprised of a gas-fired steam boiler
system (this system resides both within and outside station 101,
most of which is not shown) to produce a maximum steam flow of 25
KG/H, at a pressure of 150 psi., a pressure reducing valve with
pressure indicators, a positioner control valve (from Burkert, for
example), a steam flow control shut-off valve 1317, steam check
valves (including one pressure indicator), a membrane steam
contactor assembly (utilizing, for example, a Penberthy Steam Jet
heater), and associated pipe spools. The membrane assembly is a
stainless steel unit consisting of eight major components (intake
flange with steam injection connection, end flange, two reducer
bushings, outer pipe housing 1311, porous steam diffuser membrane
1313 (made of sintered metal, ceramic, glass or other materials),
static inline mixer 1315, two high temperature seals, and four
assembly stud bolts, lock washers and nuts.
[0132] The center piece is static inline mixer 1315 which sits
inside of membrane 1313. The membrane itself is located inside the
outer pipe housing. The smaller membrane diameter in conjunction
with the larger pipe housing diameter provides the necessary ring
room around the membrane, for the three dimensional diffusive steam
transfer through the membrane into the feed water. These parts are
end sealed by the seals, centered by the intake flange and end
flange, and held together by the fasteners. The reducer bushings
provide the connection between the smaller water lines and larger
flanges of the membrane contactor assembly.
[0133] FIG. 13 also illustrates a second configuration of the
pre-treatments suite stages 701 through 707 (sludge accumulation,
concentration and return is not shown). Feed and return pumps 1319
and 1321 are the primary effluent pumps in the system. Several
level sight glasses 1323 are deployed for operator oversight.
[0134] The primary function of stages 403, 405, 407 and
pre-treatment suite 411 is the removal or significant reduction
(exceeding 90%) of materials having total suspended solids (TSS)
down to 100 .mu.m, Fe and Mn precipitation of exceeding 80%,
CH.sub.4 gas stripping exceeding 90%, and mineralization of the
organic contaminants exceeding 50%. The mechanical processes shown
in the FIGURES include screen filtration, scraping edge and/or
automatic backflush filtration. The physical treatment processes
include membrane aeration, adsorption, desorption, precipitation,
and sedimentation. The chemical treatment processes provided
include absorption and oxidation.
[0135] Referring to FIG. 13, incoming raw feed water is blended in
venturi water contactor 703 with oversaturated recirculation water.
Venturi water contactor 703 provides homogenization of the raw feed
water with the aerated recirculation water, and provides an
environment for contacts between the suspended particles by fluid
motion (orthokinetic flocculation). Agitation of suspension by
increasing collision frequency promotes faster aggregation than
does Brownian motion alone. Orthokinetic flocculation nearly always
takes place in turbulent flow, in some form of shear conditions as
can be provided by means, for example, of a cyclonic disperser.
[0136] The homogenized discharge from contactor 703 is fed through
spray degassing sparger system 1325, the spray providing a
preliminary degassing effect. Spray degasser sparger 1325 is
mounted beneath a sealed lid 1327, and protrudes in the otherwise
unused dead volume of lamella separator 707 above the clarification
area. 55.degree. inclined corrugated baffle plates 1329 of an
inline cascade series waterfall 1331. The aerated gaseous spray is
thus broken down into thin film layers and entrained fine droplets
as it flows down surfaces creating a large thin contact area for
gas and water.
[0137] The vacuum provided by the modified gas evacuator 705 is
used for supplying the operating vacuum and pressure differential
to induce gas release from solution, and to provide the motive
force to evacuate the degassed loading of free CH.sub.4 gas or
other gasses from the degassing portion of the enclosed
pre-treatment tank system at 707.
[0138] Because of droplet surface tension, a higher pressure is
present in the aerated droplets which are entrained in the thin
film layers on the plates (a lower bubble point). Therefore, to
enhance degassing efficiency, optional to the corrugated plate
degassing system, feed water heating at heater 409 is provided.
[0139] FIG. 14 illustrates a preferred embodiment of modified
venturi gas liberator 705. The unit includes suction chamber 1401
with a 21.degree. nozzle 1403 in cone 1405. Gas (CH.sub.4) is drawn
into chamber 1401 through inlet 1407 by pressurized air introduced
at inlet 1409 from rotary vane blower 1411 (FIG. 13) through
venturi cone 1405. Parallel section 1413 is connected at
nozzle/cone 1403/1405 leading to 6.degree. discharge diffuser 1415
discharging the CH.sub.4 and air combination (to outlet stack 109
either directly or through adsorption filtration unit 1417--see
FIG. 13).
[0140] ODE membrane aeration stage 701 shown in FIG. 13 provides
oxidation for Fe and Mn contamination in the feed water, and
preferably includes tubular or capillar membrane bundles. Feed
water flows inside of tubular bundle or capillar membranes bundle
1333, whereat compressor 1334 supplies a continuous flow of volume
and pressure controlled compressed atmospheric air at a pressure
greater than water pressure. Feed water flows under minimal
pressure inside of the tubular micro-filtration membrane 1333 and
is continuously aerated from the outside of the membrane to the
inside. Obstruction or clogging of the membrane pores from the feed
water is thus avoided. Controls employed at stage 701 allow a
minimum required power input to facilitate either the deironation
or degasification process or both. The liquid and air flow volumes
as well as their pressure readings are recorded by the onboard
diagnostic systems and are scaled to determine full-size plant
requirements. Since testings are done on-site, altitude and
corresponding oxygen saturation levels are accounted for
automatically.
[0141] The aerated feed water enters air bubble reactor 1335 and,
after exiting at the top, is diffused at diffuser 1337 below the
water surface lamella tank 707. If only deironation and/or
manganese reduction needs to be done, no bubbles need to be present
in reactor 1335. In such case, if air bubbles are shown in bubble
reactor 1335, air flow is throttled back at valve 1339. An oxygen
meter aids control of valve 1339 operation, and data output
provides a permanent record for diagnostic purposes and full scale
plant design.
[0142] A suction sparger 1341 is located on top the sludge chamber
1342. Thus, elevated suction for circulation pump 1343 minimizes
recirculation of precipitated and sedimentated matter. Sparger 1341
has an elongated head to prevent suction channeling, while at the
same time providing a positive suction head for recirculation pump
1343. Pump 1343 discharge feeds first through a selective inline
filtration systems 1344. Two outlet streams result, the adjustable
larger stream providing the motive fluid force for venturi water
contactor 703 and the smaller stream being recirculated through
membrane aeration stage 701.
[0143] The sedimentation process of precipitated iron and manganese
as well as other suspended solid particles in sludge chamber 1342
goes through three phases: sedimentation of particles without
interference with each other; transfer zone with interference; and
compression, the particles forming a cohesive sludge layer.
[0144] Membrane aeration apparatus 701 and 803 at suites 411 and
413 respectively are advantageous in that a highly controllable,
diffusive, mass transfer generating a large number of small and
well-distributed bubbles with a large combined surface area, is
more effective than a small number of large and not
well-distributed bubbles with a small combined surface area, for
instance generated by a less controllable venturi mass transfer
technology. This diffusive mass transfer of air and/or ionized air
or gas is a more economical technology compared to heretofore known
approaches for mass transfer of ionized air/gas into a
suspension.
[0145] Fluid density reduction at apparatus 702 creates an
environment for increased turbulent micro bubble ascension,
accelerating the degassing process, thereby requiring less degasser
separation area for modified vacuum tower degassing at stage 703.
In addition, the decreased density of the feed water provides
reduced carrying capacity for heavier suspended solids thus
expediting descent and sedimentation.
[0146] Standard air stone degasser technology is employed at
apparatus 704 to efficiently aerate fluid at lamella separator 707
in clarifier section 1349. This is done to facilitate the release
or reduction of entrained carry-over gas through the integrated
lamella separator 707 in the event of critically high CH.sub.4 gas
loading. Likewise, fine filtration at apparatus 706 in the range of
100 .mu.m is provided by commercially available self-cleaning
automatically operating filtration units such as the standard edge
filter unit from WFT or TEKILEEN's Minitwist series low-flow fully
automatic self-cleaning filtration system. Fine filtration
apparatus 706 is configured to filter the clarifier 707
fluid/effluent. The clarified fluid is pumped from the clarifier
buffer tank compartment 1350 by means of filter pump 1345. Filter
pump 1345 is gravity-fed through suction sparger 1346, located in
the elevated section of the clarifier's small sludge chamber 1347
to avoid the suction intake of entrained air produced by air stone
apparatus 704 and precipitated, as well as sedimentated, matter
from small sludge chamber 1347.
[0147] Regarding lamella unit 707, a two in one tank design is
employed wherein a large clarifier, development and degassing tank
section with attached large sludge chamber is separated from a
small clarifier catch and buffer tank with attached small sludge
chamber by integrated lamella separator 1348. Self-sealing lid 1327
is activated by the controlled operating vacuum. The design of the
integrated lamella separator 1348 into clarifier tank system 707
provides additional clarification area without increasing the
working volume of the clarifier, thus providing a reduced
footprint. Sludge return is fed into low shear return pump 1321 and
could be (with appropriate valve control) re-circulated through the
venturi water contactor 703 before collection.
[0148] Turning to FIG. 15, another embodiment 1501 of ODE membrane
aeration stage 701 is shown. As in the embodiment shown in FIG. 13,
this embodiment includes tubular bundle or capillar membranes
bundle 1333, with compressor 1334 supplying a continuous flow of
volume and pressure controlled compressed atmospheric air. Aerated
feed water enters air bubble reactor 1335 and, after exiting at the
top, is diffused at diffuser 1337. Air flow is controlled a
variable valve 1339. However, between compressor 1334 and bundle
1333, the air is ionized at ionized gas generator 1503 for
decontamination of membrane bundle 1333.
[0149] With reference to FIGS. 16 through 23, various embodiments
of components of second pre-treatment suite 413 are discussed (see
also FIG. 8). Regarding both ionized air/gas generation apparatus
804 and membrane aeration apparatus 803, in accordance with another
aspect of this invention, improved ion treatment and reactor
technologies, applications and methods of use are described. This
aspect of the invention relates to effluent treatment utilizing
ionized air or gas and membrane aeration, and has its objects,
among others, enhanced ionized gas transfer through known membrane
aeration technology providing energy efficiency over conventional
venturi technology. Using this technology, ionized gas transfer
into feed water is further enhanced by means of a static-in-line
mixing comprising, for example, a progressive single coil system or
an electrically charged dual coil system made from conductive but
non-sacrificial material such as synthetic graphite.
[0150] As will be seen, an integrated coil mixing system is
conveniently located between a portion of the outer membrane side
and the inner reactor wall of the liquid side. A gas ionization
chamber is an integrated part of the membrane support body. A
radioactive energy source for gas ionization may be utilized, and
is directly connected to the ionization chamber thus minimizing
occurrences of recombination of ion pairs prior to their diffusive
transfer into the liquid phase. Transparency of the reactor's
housing and coil support body allows for visual inspection of the
microbubble column and is controllable through means of associated
valving conveniently located on a reactor mounting panel. The
reactor's ionized air input is monitored and controlled by means of
an in-line oxygen sensor and controller unit. The feed quality is
monitored and controlled by means of conductivity meters at the
incoming feed and the outgoing treated water lines.
[0151] In order to affect a reasonable fallout rate of contaminants
in the water after electro-coagulation, it is necessary to add a
chemical polymer prior to the electro-coagulation cell. If no
chemical is added, fallout rates are unacceptably long. For a full
size plant, this adds a burdensome financial component with respect
to chemical costs and plant footprint. Slow fallout rates translate
into large tanks for increased retention times.
[0152] Ionized air is a well recognized and employed technology in
the field of air purification. By creating a large number of
negatively charged oxygen ions and positively charged nitrogen ion,
the ions then released into the air where they attach themselves to
floating particulate matter of opposing charge, heavier particles
are created through charge neutralization thus allowing them to
fall to the ground effectively reducing airborne contaminants. The
following teaches similar approaches at apparatus 803 and 804 of
pre-treatment suite 413 for agglomerating, or coagulating,
waterborne contaminants which are otherwise too small or
incorrectly charged for easy removal.
[0153] Most waterborne contaminants in particulate form are
charged. The charge can be positive or negative, although most
particles in certain post industrial effluents (such as coal bed
methane water) develop a negative charge. When the particulate
matter freely floats in water, they are continuously being repelled
by each other, this repelling action making the particles difficult
to agglomerate to form a more easily removable mass.
[0154] By introducing a stream of negatively and positively charged
ions into the water, one can effectively neutralize the particles
specific charges thus allowing them to be brought into intimate
contact to form more easily precipitated matter. Once the
interparticle repulsive forces have been neutralized, the fallout
rate in and after processing by electro-coagulation apparatus 805
will be enhanced and chemical treatment needs will be eliminated or
drastically reduced. This process might also speed up and enhance
the iron and manganese precipitation process as well. Finally,
these ions are also very disinfective to harmful biologic
components present in some feed waters presented for treatment and
its holding tanks.
[0155] FIG. 16 shows a first embodiment 1601 of membrane aeration
apparatus 803 of second pre-treatment suite 413. Air is received at
compressor 1603 and separation vessel 1605. Output from vessel 1605
is exposed at VUV/UV unit 1607 (an annular incoherent exciter UV
source with inward directed, coaxial, radiation geometry for UV
radiation in the 130-160 nm range), the air and/or plasma-gas being
fed through a perforated membrane support body 1609 equipped with
coiled feed grooves having spring 1610 thereat. Support body 1609
carries membrane sleeve 1611 with the active membrane side facing
outwardly. Membrane sleeve 1611 is sealed on both ends of
cylindrical support body 1609. Hydrophobe, anti-adhesive,
semi-permeable membranes are employed for this ODE/IDI process (any
flat commercially available flat sheet membrane can be used). The
entering air and/or plasma-gas through the passive membrane side of
membrane sleeve 1611 has a slightly higher pressure than the
outside liquid pressure on the active membrane side, thereby
avoiding the initiation of a filtration process.
[0156] Liquid is fed at input 1613 around support body 1609 and
over and around the active membrane side of sleeve 1611 along
grooves 1610 in a coiled manner. This provides a well distributed,
non-plugging turbulent flow regime over the net active membrane
area which also enhances blending and particle collisions. Spring
1610 of the coiled feed path is a preferably a PTFE coated 300
series stainless steel spring or a PVC spring. Spring 1610 securely
rests in a matching groove inside of a clear PVC outer housing body
(not shown). Unit treated water output passes through separation
vessel 1615 before output to subsequent treatment apparatus.
[0157] The higher air and/or plasma-gas pressure provides adequate
sealing action between the active membrane side and the coiled feed
path. The thickness of the coiled feed path in relation to membrane
sleeve 1611 diameter is in the range of 1:5 to 1:500. Coil feed
path length in relation to sleeve 1611 length is in the range of
2:1 to 200:1. As maybe appreciated membrane cost savings are
realized while ease of membrane exchange or replacement and large
membrane area are provided. Visual inspection of bubble generation
is allowed through the clear outer housing body enabling better
bubble control. Embodiment 1601 maximizes efficiency due to
integrated non-plugging inline mixing (no added static inline
mixing device is needed) and compact design.
[0158] FIG. 17 shows a second embodiment 1701 of membrane aeration
apparatus 803 of second pre-treatment suite 413 (similar elements
retaining numbering from prior occurrence). In this second ODE
variation, tubular or capillar membrane bundles are employed at
aerator unit 1703. Pretreated feed water flows through input 1705
inside the tubular or capillar membranes, again at a lower pressure
than from the outside applied air and/or plasma-gas received at the
unit at input 1707. Flow from unit 1703 is received at in-line
static mixer 1709 and bubble development control column 1711 prior
to output.
[0159] The air and/or plasma-gas diffuses with only a slightly
higher pressure above the liquid pressure through the
semi-permeable tubular or capillar membrane without initiation of
the filtration process. Feed water is continuously aerated and/or
gassed with plasma-gas through the tubular or capillar
semi-permeable membrane from the passive outside to the active
inside thus reducing obstruction or clogging of the membrane pores.
The membrane inside diameter is in the range of 1 to 10 mm. The
membrane wall thickness range is between 0.1 and 1 mm. Preferred
membrane materials (for this, the previous and the following
aeration apparatus embodiments) are PVDF, PP, PE, HPE, PTFE and
PFA.
[0160] FIG. 18 shows a third embodiment 1801 of membrane aeration
apparatus 803 based on inline diffusive ionization (IDI). Similar
elements retain their numbering from prior occurrences. UV-based
treatment processes for air and water have long been commercially
available. Where economically acceptable this kind of equipment can
be readily configured for use with ODE technology (as shown in
FIGS. 16 and 17).
[0161] Most manufactures of UV-based technology do not offer
industrial hardened units in the proper wavelength range for
post-industrial applications such as oilfield use. Pulsed UV is
still a rarity in the far UV range of 130 to 160 nm. The available
UV equipment is expensive, has low UV bulb life, and has high
energy consumption requirements.
[0162] The IDI implementation of this invention integrates a proven
and readily available polonium origin particle emitter 1803 (for
example, from NDR, Inc.) with a modified ODE contact reactor 1804
having a compact and industrial hardened design. Particle emitter
1803 is used to create a highly ionized stream of air/gas through
ball valve 1805 into reactor 1804 for infusing a liquid through the
reactor membrane, the number of free electrons approximately equal
to the number of positive ions (known as plasma gas).
[0163] Emitter 1803 uses the naturally occurring radio isotope
Polonium 210 as the internal energy source for emitting unstable
nuclei of Po210 atoms in the form of .alpha.-particles (in essence
an inert helium atom (4/2 He) stripped of its electrons). The
ejection energy is high enough to cause the ionization of O.sub.2
molecules of the air (5.3 million electron volts).
.alpha.-particles carry a positive charge of low density, and, in
collision with atoms in air, knock electrons out of oxygen and
nitrogen atoms. This ability to scatter electrons and send them to
other molecules leaves positive nitrogen and oxygen molecules and
forms negative ions. In this way, the collisions produce positive
and negative ion pairs that result in an inherently balanced ion
output from the nuclear ionizer emitter 1803. Each .alpha.-particle
produces about 134,000 ion pairs, and there are 2.2.times.1012
.alpha.-particles emitted per minute per curie.
[0164] These positive and negative pairs like all air ions, no
matter how they are produced, will recombine. Since the ions must
reach the feed water to neutralize the feed water contaminants
before they neutralize each other, a compressed air/gas stream is
used to diffusively aerate the ionized air or gas through the
hydrophobic membrane of reactor 1804 to reach contaminants in the
feed water. Because a radioactive source is used, no electrical
usage is required. Since the radioactive emission cannot be
influenced by either physical or chemical means, it is not
necessary to employ highly transparent and reflective reactor
materials such as those employed in air ionization with UV
technology.
[0165] Emitter 1803 can be built directly into contact reactor
1804, which is not possible with UV or Corona discharge means. This
shortens the time necessary for transmission in the system.
OH-radicals last only 10 milliseconds in water, and only 1 second
in air. Since these lifetimes in air are so brief, it becomes
imperative to produce the radical and subject it to the water
stream in as short a time frame as possible. Contact mixing
efficiency is further enhanced by means of a progressive flow path
which is coiled around the reactor membrane (as discussed
hereinabove). Generally, the fluence (ionized air dosage) decreases
as the feed water flow rate increases because the residence time in
the contact reactor is inversely proportional to the feed water
flow rate. However, the dependence is non-linear because at higher
flow rates the radial mixing efficiency of the static inline
progressive coil mixing element increases. The gas primarily will
consist of H.sub.2O as water vapor in the air, O.sub.2 and N.sub.2
from the air. To control the amount of H.sub.2O in the feed gas, as
with the other embodiments, the gas passes through separator
1605.
[0166] FIG. 19 shows a fourth embodiment 1901 of membrane aeration
apparatus 803 of second pre-treatment suite 413 (similar elements
retaining numbering from prior occurrence). Here, the radial mixing
is enhanced through means of an electrically charged
Dualplex-start-Coil-System (DSC) mixing system. The DSC consists of
two independent, non-touching coils 1903 with an even pitch spacing
twisted around the membrane. The coils are situated in the space
between the outside diameter of the membrane and the inside
diameter of the grooved support body. These coils are made of
non-sacrificial, but conductive material, for instance graphite or
graphite coated support material.
[0167] The proper non-touching spacing between the two coils is
provided and secured through a thinwalled duplex-start grooved
support body, made of clear nonconductive PVC. The duplex-starts in
the support body are offset to each other (i.e., turned by
180.degree.). Pitch of each coil and groove of one inch, providing
a pitch distance of half an inch between the two independent coils,
suggest good performance for most applications. The coils are
screwed into the support body concurrently and the support body is
inserted as a cartridge into a reactor glass body tube. The outer
support body diameter is sealed against the body tube (using
O-rings, for example).
[0168] AC power is received at connector 1905 connected to coils
1903 at a vessel cap 1907. The vessel cap in configured to provide
for electrical connection away from the liquid phase. In essence
this embodiment operates similar to an electrocoagulation system
with non-sacrificial electrodes, the electrically charged mixing
coils 1903 representing the electrodes and the pitch spacing
representing the electrode C--C distance. The operating current of
the system is preferably 4 amps with a frequency converter setting
of between 1 and 10 hertz.
[0169] While shown utilizing the emitter 1803 of the third
embodiment, this embodiment can be employed also with photo (UV)
initiated air ionization technology. If radioactive initiated air
ionization is employed, the positively charged .alpha.-particles
will deflect towards the negatively charged electrical field. The
frequency controlled alternating deflection of the
.alpha.-particles takes place primarily within the upper portion of
the ionization chamber. This alternating deflection provides
additional collision potentials with the continual incoming large
number of neutral air molecules, thus slowing the recombination of
positive and negative ion pairs prior to exposure to the
contaminated effluent.
[0170] The alternating current flow provides an enhanced
distribution environment for the diffusively aerated ionized
air/gas for balancing the surface charge of particles in the feed
water solution thus removing or reducing the electrical repulsive
charge on the particles. This hydrodynamic mixing energy, provided
through the differential pressure of the flow altering coil system,
generates a turbulent fluid motion environment for interparticle
contacts, sometimes called orthokinetik flocculation. The
interparticle contacts of charge neutralized materials (for
example, colloids) now destabilizes out of the dispersion, followed
by collision of destabilized particles to form aggregates. The
aggregation of these particles into larger more easily settled
aggregates is necessary for efficiency enhancement of following
processes where separation by precipitation, sedimentation and
flotation takes place.
[0171] Reactor unit 1804 is shown in FIG. 20 (though many of the
features thereof are similar to others of the reactors units shown
in FIGS. 16, 18 and 19. The unit includes perforated membrane
support body 2001 equipped with coiled gas feed grooves 2003 having
positive pitch. Gain twist mixing coil 2005 facilitates fluid flow
and secures hydrophobic membrane sleeve 2007 on support body 2001,
the active membrane side facing outwardly. Membrane sleeve 2007 is
sealed on both ends of cylindrical support body 2001.
[0172] This assembly is received in clear reactor sight glass/outer
body 2008, upper and Lower caps 2009 and 2011 applied and sealed
thereat by O-rings 2013 and 2015, respectively. Feed inlet port
2017 is defined in cap 2009 and retainer and transfer plug 2019 is
received between cap 2011 and outer body 2008 for, in combination
with a series of included fluid transfer holes 2020 adjacent to
conical end 2021 of support body 2019, channeling flow at flow
channel 2023 to outlet port 2025 defined in cap 2011. The
compressed stream of ionized air/gas received from emitter 1803 is
received into support body expansion chamber 2027 through port
2029. Slots 2031 are formed around support body 2001 for less
obstructed ionized air transfer through membrane sleeve 2007 into
the aqueous flow.
[0173] In unit 1804, the ionization of the induced air and the
diffusive transfer of the ionized air through the reactor membrane
into the feed water starts in the upper portion of the reactor
chamber, into the starting point of turbulence. The turbulence is
generated by means of the progressive flow path coiled around the
reactor membrane. The gain twist coil path provides a high energy
efficient collision environment for the ionically destabilized
particles in the feed water to form aggregates. The key to the high
energy efficiency of the progressive gain twist static inline
mixing coil lies in the fact that it substantially operates as a
plug flow device. All material passing through it receives the same
blending experience. The same amount of energy or foot pounds of
work per gallon has been expended on all the incoming feed water.
None is over-blended and none is under-blended.
[0174] All embodiments shown in FIGS. 16 and 18 through 20 are much
more effective than conventional venturi technology for the ionized
air-liquid-solids systems. The diffusive ODE/IDI technology
provides a defined three-dimensional diffusive phase contact
transfer environment with the medium. Since conventional venturi
type blending does not provide such a defined phase contact area,
the phase contact within the molecular and micron range takes place
by undefined chance rather than design and, therefore, lacks
effectiveness by comparison.
[0175] Furthermore, the conventional venturi contactor works with a
relative low pressure differential and, therefore, a low vacuum
suction for air and/or ionized gas. In contrast, the higher and
variable pressure operating membrane technology herein diffuses
more air for bubble generation and/or ionized gas effectively into
the feed medium. While recirculation can be provided, ODE/IDI
systems of this invention are effective in a once through on the
fly treatment. With the integration of the ODE/IDI units of this
invention a reduction of operating costs through energy savings and
capital cost for reactor construction are realized, and a smaller
station foot print is enabled.
[0176] FIGS. 21 through 23 show various other apparatus of second
pre-treatment suite 413, FIG. 21 illustrating a particular
arrangement of suite 413 including the ten apparatus 801 through
810 heretofore identified configured with selected piping, flow
control and instrumentation configuration. IDI inline ionizer unit
804 may be any known alpha ionizer such as the STATICMASTER series
form NRD and related instrumentation. Level sight glasses 2101 and
2102 allow convenient on-site process inspection. Output from suite
413 proceeds to stage 415 (step 7) including bag filter system 2105
and belt filter system 2107.
[0177] In accordance with another aspect of this invention, FIG. 21
through 23 and the following description illustrate the
electrocoagulation apparatus and configuration in station 101 of
this invention. Electrocoagulation apparatus 805 operates
conventionally but includes a number of unconventional features. In
addition, apparatus 805 is positioned in tank 2111 (the larger of
the two tanks 2111 and 2113 separated by separator plate 2115) of
lamella plate clarifier apparatus 809. Electrocoagulation operates
by the splitting off of ions from sacrificial or non-sacrificial
electrodes in apparatus 805 into the water presented for treatment
to destabilize suspended, emulsified or dissolved contaminants in
the water by introduction of an electrical current. The water acts
as an electric conductor in which current is carried, thus forming
a hydroxide compound. The most common sacrificial electrodes
utilized in such apparatus are made of iron or aluminum, the most
common non-sacrificial electrodes being made of carbon.
[0178] Present electrocoagulation art does not adequately address
the mechanisms of flotation, sedimentation and the circulation
effect of coagulant aggregation in the early stages as bridging
flocs. In the electrocoagulation process, the partially lighter
aggregated coagulants are transported to the liquid surface by
their attachment onto the ascending electrolytic gas bubbles. The
remaining, predominantly heavier, aggregated coagulants bridge to
heavier, larger flocs and precipitate out into a sediment
layer.
[0179] Treatment analysis in advance of establishment of the
treatment regimen determines the necessary mass quantity of matter
that needs to be deposited by the sacrificial electrodes. For
diagnostic real time capability, the electrocoagulation reactor
described hereinafter may be equipped with selective multiple
electrolytic cell choices (14 cells, for example) in the primary
reactor chamber.
[0180] In accordance with this aspect of the invention, the
following relates to electrical apparatus for electrolytic
flotation and electrochemical dosing referred to as
electrocoagulation, and apparatus, configurations and methods for
treating contaminated waters for selective pre-treatment and/or
cleaning of the waters. Electrocoagulation presents a
cost-effective alternative to traditional methods for treatment of
certain polluted waters or as a method for the pre-treatment of
suspensions, emulsions and light sludges prior treatment with
membrane technology, for instance clean up involving gas, dissolved
and suspended solids removal from a hydraulic system where chemical
or electrochemical dosing, coagulation, electroflotation,
flocculation and sedimentation would be employed.
[0181] Apparatus 805 of this invention allows for a variety of
electrode materials to be implemented within one active electrode
plate area for numerous electrolytic treatment applications. The
apparatus is compact and portable for easy delivery and hookup at
station 101 and is used in conjunction with the other station
apparatus for blending air, plasma-gas and/or dissolved metal salts
with the feed water. As shown in FIG. 21, a plurality of pumps for
controlling the feed water flow and a plurality of conveniently
located valves, regulators and pump controls for automated or
manual control of the various functions of the apparatus 805 are
provided. Apparatus 805 is integrated directly with dissolved air
flotation apparatus 806 in clarifier apparatus 809, and is further
enhanced by integration with vacuum apparatus to accelerate the
electroflotation of the floc-foam layer to the liquid surface of
electrocoagulation reactor (together referred to herein as
"electrolytic dissolved air flotation"--EDAF--treatment).
[0182] The EDAF treatment approach utilizes a modified plate
electrocoagulation reactor design. Because electrocoagulation
reactor 805 is an integrated part of clarifier tank 2111 of lamella
apparatus 809, shear-free sludge transfer in a compact single unit
structure is provided. Vacuum enhanced electroflotation is provided
through the employment of an enclosed vacuum hood 2117 above
flotation chamber 2119 of flotation apparatus 806, to speed up the
flotation process and as well remove unwanted created or entrained
gases via vacuum degassing apparatus 808.
[0183] Vacuum hood 2117 is adjustable for proximity and vacuum lift
capability to optimize the electroflotation effect as well as
floc-foam surface layer removal at cyclone separator apparatus 807.
Hood 2117 is mounted on outer housing 2121 holding inner reactor
assembly 2123 of electrocoagulation apparatus 805. Inner assembly
2123 (FIG. 22) is defined by four corner posts 2125 (FIG. 23)
together establishing primary reaction chamber 2127 and secondary
reaction chambers 2129 and 2131 adjacent the primary chamber. The
secondary chambers provide additional electrocoagulation treatment
stages to optimize the overall electrocoagulation treatment on an
as needed basis Each secondary chamber includes an anode, cathode
and bipolar electrode 2133, 2135 and 2137, respectively, held in
corner post 2139 for insulating the secondary chambers as well as
forming supports for insulating walls 2141 of the primary chamber.
A small jet of previously clarified process water received through
conduits 2142 washes electrode 2137
[0184] Conical sludge chamber 2143 is formed below primary reaction
chamber 2127 and vacuum/flotation chamber 2119 of flotation
apparatus 806 is formed below chamber 2127. Primary electrode
plates (either sacrificial or, preferably, non-sacrificial) are
held at a plurality of electrode positioners 2145 at opposed
chamber walls. This electrode framework allows rapid electrode
interchangeability and/or electrode set ups specially adapted to
site circumstances. For example, a composite electrode setup with
electrodes of different materials combined within a single
electrode stack could be utilized for treatment of complex feed
waters. Bipolar electrodes 2137 of secondary chambers 2129 and 2131
are readily accessible for maintenance purposes.
[0185] Integrated sludge chamber 2143 provides buoyancy and/or
electromechanically actuated sludge transfer via a sludge cone
valve 2149. Sludge is transferred from sludge chamber 2143 into the
fluid bed of the sludge holding/disposal chamber 810 at lamella
clarifier tank 2111 of clarifier apparatus 809, thus minimizing a
shear introducing gradient to the delicate floc structure within
the sedimentated electrocoagulation sludge. This eliminates or
greatly reduces the need for expensive floc polymers and/or
coagulants as well as reducing energy requirements for the floc
rebuilding process. A compound sludge chamber angle of repose of
35.degree. for hydroxide sludge is employed thus, in conjunction
with a matching sludge cone release valve, preventing sludge build
up within the chamber and expediting sludge release.
[0186] A variable discharge head and distribution system may be
employed to minimize surface floc-foam layer carry over from the
primary chamber and provide suitable discharge distribution
geometry into secondary electrocoagulation chamber(s), thus
minimizing channeling and ensuring effective electrocoagulation
treatment in the secondary electrocoagulation. Secondary
electrocoagulation flow control may be provided through discharge
disks and dampener adjustment to ascertain proper flow
distribution, retention time and minimize channeling, providing an
effective secondary and efficient overall electrocoagulation
treatment.
[0187] Multiple flat bar electrodes 2203 forming multiple electrode
stacks 2205 (only one shown in FIG. 22) are employed. These
standard vertical stacks consist of electrode bars 2203 arranged
one on top of another. Horizontal stacks 2205 may be arranged with
electrode bars 2203 in a side by side arrangement (instead on atop
one another) and secured by a top contactor clip which also
provides current transfer from one stack 2205 to the next. The
vertical multi-flat bar stack 2205 arrangement is more suitable to
maximize sacrificial electrode life. The sacrifice of electrode
material is more pronounced on the leading edge/area of the
ascending feed water flow in a downward or upward directed
parabolic shape. The leading edge problem can be minimized by
substituting the bottom bar with a nonmetallic, but conductive
graphite bar. If unacceptable, a new sacrificial bottom bar needs
to be added from time to time between whole stack replacements.
[0188] The vertical multi-flat bar option provides a mechanism for
active electrode area reduction without sacrificing reactor
retention time by insertion of dielectric/nonconductive plate area
(PVC or CPVC) into the vertical stack electrode structure in place
of active electrode bar(s). This allows varying of the active
surface area to volume ratio to find the optimum ratio for a
particular application. This variable ratio option is an important
feature in establishing scale-up of this parameter.
[0189] Required electrical field strength (dependent upon
concentration levels and contaminant types in the feed water) can
be manipulated by varying electrode C--C spacing for treatment
optimization. Primary electrocoagulation facilities at 2127 are
powered with a variably applied amperage in the range of 0.1 to 60
amps. With electrode bars set in series connection mode, the same
current flows through all the electrodes and voltage is allowed to
vary as electrocoagulation treatment progresses over time.
[0190] A crossflow electrode flushing capability option through
valve 2151 is preferably provided to create a turbulent flow regime
with the ascending water flow in primary electrocoagulation reactor
chamber 2127 and with the descending flow within the secondary
electrocoagulation reactor chambers 2129 and 2131. Flow direction
of flush water jetting is staggered crosswise and perpendicular to
the electrocoagulation process water flow over the electrode
plates. The directed turbulent flow continually washes the sides of
the electrodes and prevents or significantly retards the build-up
of impermeable oxide layers (passive) on the cathode as well as
deterioration of the anode due to oxidation. This can be done
instead of polarity switching or, in a fine regulated mode, in
addition to polarity switching in severe scaling situations or in
applications that contain heavy amounts of grease or oils.
[0191] A small jet of previously clarified and pressurized process
water flow is constantly or time sequentially introduced into the
electrocoagulation process water flow through a plurality small (
1/32'', for example) holes drilled into electrode positioners 2145
at primary electrocoagulation reactor chamber 2127. Secondary
electrocoagulation reactor chambers 2129 and 2131 have a plurality
of similar holes 2142 drilled into spaces at insulating corner post
2139 between and close to the electrodes.
[0192] The three phase separation and removal areas of
electrocoagulation reactor apparatus 805 operates as a standard
parallel electrode unit (in a fluidized bed configuration a
different arrangement would be applied). In phase one, light
flotation solids in the floc-foam, gas (H.sub.2 and O.sub.2), and
oil and grease layers are separated at the liquid surface and
removed by the adjustable vacuum at vacuum chamber 2119. In phase
two, the semi-clarified effluent of the primary electrocoagulation
treated water is separated from underneath the floc-foam surface
layer at chamber 2127 and is removed or transferred through
adjustable disk head control devices into the secondary
electrocoagulation reactor chambers 2129/2131. It is here either
optionally treated or directly discharged into the settling portion
of the lamella clarifier tank 2111 to develop clarity prior to
discharge from the lamella separator 2115 overflow into the clear
flow catch tank 2113. In phase 3, the solids precipitate out into
integrated primary electrocoagulation sludge chamber 2143,
proceeding through the normal sedimentation process mechanics.
[0193] When operating electrocoagulation apparatus 805 with
non-sacrificial electrodes, for instances with electrically
conductive synthetic graphite electrodes, the necessary positively
charged ions for maintaining the electrocoagulation process are
partially provided by the feed water itself. The remaining part of
the required positively charged ions are added in form of metallic
ions such as Al+, Ca+, Fe+ and Mg+ salts. For an enhanced electron
migration, the electrocoagulation process should be operated within
the acidic range through chemical dosing with hydrochloric (HCl),
sulfuric (HS.sub.2O.sub.4) or phosphoric acid (H.sub.3PO.sub.4).
Utilization of synthetic graphite electrodes avoids the
consumption, replacement and operating down-time associated with
conventional sacrificial electrodes, and reduces energy and
maintenance costs. Moreover, metallic salts are less expensive than
the refined, finished, sawcut and otherwise machined or fabricated
sacrificial metal electrode plates.
[0194] To facilitate feed into chamber 2127, a longitudinal tube
turns for net feed area adjustment inside of the stationary 11/4''
base pipe, a defined net opening slot area distributing the whole
feed through the whole length of primary electrocoagulation reactor
chamber 2127. To facilitate discharge from inner reactor assembly
2123, discharge weir disk orifices are preferably provided for flow
control from chamber 2127 or into secondary chambers 2129 and/or
2131. To prevent surface foam carry over into the secondary
electrocoagulation treatment chambers, a positive head above the
center of these orifices needs to be maintained at all times.
[0195] Through simple contact plunger manipulation at an easily
accessible multinode terminal bar or bars adjacent the electrodes
(either manual or automated contact manipulation could be
deployed), electrocoagulation reactor operating circuitry can be
arranged for different modes of operation. For parallel operation,
contact plungers are provided at each electrode node at a terminal
bar. This arrangement of the electrocoagulation reactor circuitry
provides parallel connection using monopolar electrodes. In this
mode, the electric current is divided between all of the electrodes
in relation to the resistance of the individual cells. The same
voltage is present in all of the contact plungers. Varying the
current controls the rate of electrochemical activity
[0196] For series operation, one contact plunger remains active at
the terminal bar furthest from the source power connections.
Insulated jumpers connect the nodes. In this mode of operation the
contactor terminal bar provides series connection for the monopolar
electrodes in the electrocoagulation reactor. In series cell
arrangements, a higher potential difference is required for a given
current to flow, because of higher cumulative resistance. The same
current would, however, flow through all the electrodes. Varying
the voltage controls the rate of electrochemical activity.
[0197] In a parallel, bipolar configuration (as shown in the
secondary chambers 2129 and 2131, but which could be applied
primarily), one contact plunger at both contactor terminal bars
remains, the one furthest from the source power connections. Only
the monopolar anode and cathode electrodes are connected to the
electrical power connections. In this mode, bipolar electrodes with
cells in parallel are used. The bipolar electrodes are placed
between the two parallel anode/cathode electrodes without any
electrical connections. When an electric current is passed through
the two electrodes, the neutral sides of the conductive plate of
the bipolar electrodes will be transformed to charged sides, which
have opposite charge compared to the parallel side beside it. This
cell arrangement provides, where applicable, a desirable testing
platform for a full scale unit application. Its simple set-up and
maintenance can lower the overall electrocoagulation operating
cost.
[0198] A mixed parallel and series configuration could be provided,
providing individual mixed cell circuitry configurations. For
instance, in a fourteen cell reactor, half the cells could be
connected in a series circuitry and the remaining seven cells
connected in parallel, either as monopolar, bipolar or in mixed
mode. This option can be used as a diagnostic tool when different
amperages are needed for different electrode materials within the
primary electrocoagulation reactor for specific treatment
situations.
[0199] These parallel or series power connection choices are
implemented by spring loaded contactor bars with integrated
connection interchangeability (plungers). DC or AC operating power
options with variable current density controls are implementable
for control of electrochemical dosing and electrolytic bubble
density production for sacrificial electrodes, as well as
regulating the required transport current for the required added
positively charged ions when nonmetallic and non-sacrificial
electrodes are employed.
[0200] Controlled polarity switching for DC power implementations
is provided to prevent or minimize oxide build up as well as
hydrogen polarization. A vector frequency controller for the AC
power option provides for frequency control below 90 Hertz to
prevent disaggregation of agglomerated particles. To accommodate
rapid changes of electrodes and/or customization of electrode
setups, main power distribution through removable, quick release,
swing away main contactor bars, providing as well for rapid change
from parallel to series power connection, is utilized.
[0201] Regarding pre-treatment suite stages 411 and 413, zeta
potential is an important part of the electrokinetic phenomena of
interaction between particles in suspension. The zeta potential is
the electrokinetic potential of a suspended particle as determined
by its electrophoretic mobility. This electric potential causes
colloidal particles to repel each other and stay in suspension. The
zeta potential is a measurement of the overall charge
characteristic of the suspended particles in the water. Whereby the
kind and magnitude of the electrical charge depends on the surface
potential of the particles, or the zeta potential. A negative zeta
potential indicates that the water contains free negatively charged
suspended solids (common in many treatment feed waters) that are
stabilized and therefore more likely to stay in solution.
[0202] A neutral zeta potential indicates that the suspended solids
do not carry a charge to assist in their electrical repulsion of
each other. They are more likely to destabilize and coagulate into
larger particulate groups and fall out of solution, and therefore
being removed as part of the pre-treatment. The importance of the
zeta potential rests on the fact that it can be measured
experimentally and in many cases serves as a good approximation of
the unmeasurable surface potential of the colloidal particle, since
there is a fairly immobile layer of counter ions that sticks
tightly to the surface of the particle. Treatment diagnostics
herein thus uses the zeta potential measurement to gauge coagulant
requirements (if any), and can be adapted for automated adjustment
of an injected cationic (positively charged) coagulant such as
reverse osmosis Quest 6000, which could be used in pre-treatment
stage 411, to achieve a neutral zeta potential upstream of
pre-treatment stage 413. Thus utilized, suspended solids would be
more likely to fall out of solution into 2111 of clarifier 809.
[0203] Vacuum introduced cyclone separation apparatus 807 of suite
413 (FIG. 21) utilizes a conventional cyclone unit or units 2155
and 2157 connected for vacuum inducement apparatus 808 and hood
2119 and outlet for foam collection through filters 2159 and 2161,
respectively. Filtration stage 415 (step 7) makes use conventional
know bag filter systems 2105 and or belt filtration systems 2107
(such as the Roll-A-Filter or Lazy Filter fabric media systems
produced by SERFILCO. Homogenizing and buffer tank for pH and
chemical adjustment a stage 417 (step 8), and buffer tanks at
stages 425 and 431 (steps 12 and 15), make use of a standard,
commercially available tank designs (for example, polyethelene
tanks by LMI or SNYDER of adequate capacity, and with or without
containment basins). Chemical metering pumps 306, 308 and the pumps
used at stages 421 and 427 (steps 10 and 13) could be either of two
types (automated and/or manually operated). Primary chemical
injection pumps are solenoid-driven, dual manual controlled
diaphragm metering pumps having four-function valves for control of
anti-siphon, back pressure, priming, and pressure relief all in one
could be used (the metering pumps and controls by LMI Milton Roy,
for Example).
[0204] Secondary chemical injection pumping employs dual channel
peristaltic pumps for antiscalant injection, for example upstream
of nanofiltration and reverse osmosis membrane systems described
below (V-TECH--3000 at stage 421 or 4000 at stage 427--through
Masterflex pumps from Cole-Parmer Instrument Company, for example,
could be utilized).
[0205] Membrane treatment and other treatment systems utilized at
205, including stages 419 through 433 (steps 8 through 16), may be
realized by deployment of various types of apparatus and systems,
particularly at steps 9, 11, 14 and 16 (steps 8, 10, 12, 13 and 15
are primarily directed to homogenization and process buffering
and/or chemical metering, and have been addressed hereinabove).
Ion-exchange treatment and HEED systems utilizable herein have
already been addressed. In addition V-SEP series L/P systems, while
not preferred, could be utilized at stages 419, 423, 429 and 433
for analytics as well as nanofiltration and reverse osmosis filter
installations.
[0206] At stage 419, high frequency nanofiltration systems as
discussed hereinbelow could be employed. However, in accordance
with another aspect of this invention, FIG. 24 through 27
illustrate an axial vibratory membrane separation apparatus and
methods for forward osmosis. This aspect of the invention relates
to low amplitude, axial vibratory membrane separation apparatus
(both nanofiltration and reverse osmosis filtration) called quaking
recycle membrane separation technology employed with forward
osmosis technology. Forward osmosis technology is employed to
supplement the quaking membrane nanofiltration and/or reverse
osmosis technology, the hybrid application incorporated into an
integrated apparatus (high frequency forward nanofiltration or high
frequency forward reverse osmosis apparatus).
[0207] Heretofore known forward osmosis technology uses the osmotic
pressure differential across a membrane, rather than the hydraulic
pressure differential, for filtration. The osmotic pressure
differential is provided by a recyclable solute composed of a
mixture of salts, the thermally recyclable salt solution called
"draw solution".
[0208] Draw solutions typically used include ammonium bicarbonate
(NH.sub.4HCO.sub.3), ammonium carbonate (NH.sub.4).sub.2CO.sub.3,
ammonium carbamate NH.sub.4NH.sub.2CO.sub.2; (H.sub.4NO)
(CONH.sub.2;H.sub.2N--CO--O--NH.sub.4), and can preferably include
magnetoferritin in solution. The concentration of solutes in the
thermally recyclable draw is required to have a higher osmotic
pressure than the osmotic pressure of the concentration of solutes
in the feed water (often brackish). Common spiral-wound membranes
have not been heretofore utilized for forward osmosis because a
liquid stream cannot be forced to flow on the support side
(permeate side) inside the envelope, where the porous polymer layer
further increases the internal concentration polarization. The
apparatus of this aspect of the invention employs tubular or hollow
fiber membrane modules, rather than spiral-wound membrane
elements.
[0209] The hybrid quaking membrane plus forward osmosis process and
apparatus of this invention secure permeate continuity of the
present art forward osmosis technology (generating extreme
turbulence on both sides of the forward osmosis membrane (feed side
and draw side) to support permeate continuity), provide
nondestructive, vibratory membrane separation for commercially
available forward osmosis membranes, and reduce the potential
tendencies of concentration polarization, scaling and fouling of
forward osmosis membranes.
[0210] Turning to FIGS. 24 to 27, the hybrid quaking membrane plus
forward osmosis process and apparatus is illustrated with the
quaking membrane assembly at 2401 and recycle and reconcentrating
closed loop system at 2501. In the combined apparatus,
self-supported, semi-permeable or hollow fiber tubular membrane
2403 is used as a forward osmosis membrane operating in a quaking
membrane process. Such tubular and hollow fiber membranes have no
thick support layer as in spiral-wound, flat sheet, asymmetric
membranes, thus minimizing internal concentration polarization.
Membranes of this type are commercially available.
[0211] The quaking membrane process is low amplitude and high
quaking frequency, generating low shear energy and therefore a
gentle treatment in the epoxy potting compound of tubular or hollow
fiber membrane 2403. The quaking energy significantly lower already
low external concentration polarization, and has a positive effect
on internal concentration polarization as well. Sufficient
turbulence is generated on both sides of tubular or hollow fiber
membrane 2403 (external and internal) for securing continuation of
increased flux performance required by the forward osmosis process.
The process thus yields a higher permeate production with less
concentrate for disposal and requires less up front pre-treatment
for the feed, while using less energy compared to conventional
reverse osmosis/nanofiltration technology because little or no
hydraulic pressure is needed as a driving force for separation.
[0212] For a continuously operated forward osmosis process, it is
necessary that the membrane module design allows liquids to flow
freely on both sides of membrane elements. Cellulose triacetate is
the preferred material used in membrane 2403 (TOYOBO Hollosep
hollow fiber membranes, for example). Low pressurized,
recirculating feed water flows inside of the hollow fiber tubes of
the membrane module 2403 from low pressure feed recirculation pump
2405. The gravity-assisted feed flow is induced at the top of the
axial vibrating, hollow fiber module 2403.
[0213] Quaking membrane module 2403 can either be operated in a
vertical or inclined position, quaking membrane movement is
provided by means of quake generator such as high pressure
diaphragm pump 2407. The low pressurized, draw solution flows
counter currently to the feed on the outside of the hollow fiber
tubes. The draw enters at the bottom of membrane module 2403 and
exits at the top. Forced draw circulation flow is provided by
vacuum and compressor pump 2503 (FIG. 25). The concentration of the
draw solution is diluted as the high osmotic pressure of the
solution draws water through the semi-permeable membrane from the
feed medium of lesser osmotic pressure. This, in turn, requires a
reconcentration of the draw solution for the continuous
desalination process.
[0214] The diluted draw solution is thermally recycled and
reconcentrated in a closed loop system, which yields potable water.
The closed loop system consists of two heat exchangers 2505 and
2507, a stripper column 2509, and buffer tank 2511. In the closed
loop, the draw solution diluted with water is first lightly heated
to 30.degree. to 50.degree. C. in heat exchanger 2505. The heated
draw exits heat exchanger 2505 from the top and is siphoned into
stripper column 2509. Stripper column 2509 packing includes either
raschig rings or berl saddles. Stripping takes place the column,
the packing providing the necessary increased area and turbulence
to achieve a desired draw solution conversion from a liquid to a
vapor phase with the nonvolatile water precipitating out of the
draw solution.
[0215] The lightly heated, liquefied and diluted influent
(consisting of water and its soluble light volatile draw
components) is distributed (at spray head 2512, for example) at the
top of packed column bed 2513, flowing down through the bed where
the large transfer area and the vacuum assistance of pump 2503
allows the volatile components of the diluted draw to convert into
an effluent vapor phase in the upper column portion and yielding
potable water dilution water from the lower column portion (the
treatment product of this apparatus). Vacuum and compressor pump
2503 is configured to handle a large vapor volume on its suction
side and compressing the vapor on its pressure side, and transfers
the pressurized vapor from stripper column 2509 into the top of
second heat exchanger 2507 for compression heat removal from the
compressed vapor mixture. Cooling is provided by means of fresh
cold feed water.
[0216] The cooling the vapor phase yields a condensate of a highly
concentrated solute mixture and thus generates a recycled draw
solution of initial concentration strength. The vapor mixture
condensate is discharged from exchanger 2507 into buffer tank 2511.
Tank 2511 includes automatic aeration and de-aeration device 2517
to avoid the passage of residual vapor into hollow fiber module
2403. Treated water is transferred out of column 2509 by
centrifugal-vacuum pump 2519 while retentate particle separation is
achieved via hydrocyclone separator 2409 (FIG. 24). The upper
module suction provides motive force to the recycled draw solution
for flowing continuously from the lower permeate suction connection
of module 2403 upwards and towards the upper permeate discharge
connection, while the feed flows counter current to the draw
downwards inside of hollow fiber module 2403.
[0217] The apparatus of FIGS. 24 and 25 is adapted for use not only
with commercially available semi-permeable tubular and/or hollow
fiber membranes modules, but also for forward osmosis specialized
spiral-wound membranes when and if they become commercially
available. The apparatus and processes can be used in station 101,
and also in applications for any brackish water treatment, higher
contaminated CBM water treatment, overflow treatment of biological,
defecated, municipal waste water for irrigation, cleaning processes
for airplane and other public transportation wash water recycling,
processing of bilge water, processing of wash water for combat
vehicles after active and practice missions, and waste water
processing for the pharmaceutical and chemical industry.
[0218] The quaking membrane coupled with the forward osmosis
process allows a substantial concentration upgrading at stage 419
at a significantly reduced energy requirement compared to
conventional membrane separation processes, and could be employed
as well at stages 423, 429 and/or 433. Depending on the
application, quaking membrane technology provides high recovery
relative to conventional nanofiltration and/or reverse osmosis
technology. Reduced scaling and fouling tendencies of the apparatus
and processes reduce costs associated with pre-treatment stages
used in conventional nanofiltration and reverse osmosis
technology.
[0219] Quaking frequency is variable in the range of 1 to 100 Hz
depending on configuration. Quake amplitude has a relatively wide
adjustable range of 0.2 to 2.0 mm. Quaking membrane movement can be
generated either by any of electrical, hydraulic or mechanical
means through an adjustable high frequency generator. Electrical
means can include electromagnetic linear reciprocating membrane
motion apparatus through a frequency-controlled, modified linear
motion motor assembly wherein frequency and amplitude can be
adjusted dynamically over a greater range (from 1 to 100 Hz.--see
FIGS. 26 and 27).
[0220] Modified motor assembly 2601 is shown in FIGS. 26a and 26b
having an upper stator coil section 2603 and lower stator coil
section 2605, upper and lower (upper components only being shown in
FIG. 26b) fluid transferring end pieces 2407 being equipped with
encapsulated, high-energy neodymium, iron-boron, reciprocating
permanent magnet sleeves 2409. The nonmagnetic outer housing 2410
having with upper and a lower stator 2411 and retainers 2413. The
stators contain the electromagnetic coils, which utilizes 3-phase
direct drive, brushless technology. The stator's length and
diameter set the force level, while the sleeve length determines
the amplitude height.
[0221] Motor 2601 uses a dual synchronous design wherein two
stators and two permanent magnet sleeves are spaced over the entire
length of the membrane. These dual linear motors are operated
synchronously thus providing positive linear reciprocating motion
over the entire length of the membrane. Quaking membrane cartridge
at 2403 floats and is supported between an upper recoil spring
system and the lower support structure spring system (both at
2403), thus isolating membrane cartridge movement therebetween.
Spring rate is adjustable for equalization of the stator coil force
requirement between upper and lower stator coils 2411, with force
requirements based on the chosen operational quaking frequency and
amplitude.
[0222] As can be appreciated, the membrane cartridge rides up and
down between two resilient spring isolation systems within a
stationary (housing also at 2403), whereas the motive reciprocating
forces are provided by means of dual synchronously operating linear
motor assembly 2601. The two spring systems are configured to be
adjustable for vibration transmissibility and damping efficiency
(the spring system's ability to dissipate oscillatory energy and
thus not transfer the energy to the entire quaking membrane module
2403).
[0223] The modified linear motor assembly 2601 is essentially an
electric motor that has its stator configured and positioned so
that, instead of producing rotation, it produces a linear force
along its length. As shown in FIG. 27 stator coil cooling can be
accomplished utilizing a cold feed water stream (for example, from
the same cold feed stream feeding heat exchanger 2507) fed by
appropriate piping to port 2701 of ring-shaped cooler 2703 mounted
between retainer disks 2705 adjacent to stator coil 2411. Feed at
port 2701 is constantly replenished and recycled out at port 2707
connected at heat exchanger 2505.
[0224] Feedback in the forward osmosis system can be bypassed, if
operations in quaking membrane mode only is preferred, by simple
valving preventing re-osmosis of clean permeate. Three-way ball
valve 2521 functions as a selector valve for quaking membrane plus
forward osmosis mode operations or quaking membrane mode operations
only.
[0225] Osmotic pressure differential in the foregoing quaking
membrane forward osmosis apparatus and methods is preferable
provided by a magnetically recyclable solute composed of magnetic
mixture of soluble salts. The use of magnetoferritin is known but
requires removal from the aqueous stream by means of
electromagnetic separation. To minimize problems associated
therewith and with the problem of concentration polarization, FIG.
28 shows an ultrasonically active draw solution dispersion system
in accord with yet another aspect of this invention.
[0226] Alternating electrical energy from ultrasonic generator 2801
is converted to an alternating magnetic field at coil 2803 in
protective housing 2805 held around the outer housing of membrane
module 2403 by retaining disks 2807. Coil 2803 extends
substantially the entire length of module 2403. Generator 2801 is
adjustable. The oscillating magnetic field induces hydrodynamic
dispersion forces (turbulence) at ultrasonic frequencies in the
ultrasonically active draw solution including magnetoferritin. The
turbulence is at the internal boundary layer of the membrane thus
minimizing internal concentration polarization. External
concentration polarization is controlled by using a low pressure
magnetically coupled centrifugal feed pump with an elevated output
rate for producing external feed flow turbulence.
[0227] FIG. 29 shows one arrangement of components in a polishing
treatment array 205 using membrane treatment systems especially
concentrating on the integration of the membrane treatment systems
of stages 423 (step 11 using the nanofiltration membrane treatment
option) and 429 (step 14 using the reverse osmosis membrane
treatment option). These two stages implementing membrane processes
separate dissolved solids from the pre-treated water. The selection
of specific membranes and spacer material are based on test results
(for example, from on-site three-dimensional test cells such as
those shown in U.S. Pat. No. 6,059,970). The systems are set to
operate at moderately to high pressures and typically employ high
speed gravity assisted geometries with selected variable crossflow
capabilities.
[0228] Nanofiltration membrane implementation of stage 423 is a
multistage configuration, operating in series. The array includes,
for example, three pressure vessels 2901 each having a single
membrane. The primary function of nanofiltration membrane treatment
is the removal of the finest colloidal matter. The separated
colloidal matter is removed with the nanofiltration concentrate.
The produced nanofiltration permeate serves as feed the next
membrane and, ultimately, for reverse osmosis implementation of
stage 429.
[0229] The reverse osmosis implemented array of stage 429 includes,
for example, two stages, with two membranes 2903 operating in
parallel in the first stage feeding a third membrane 2905 in the
second stage. As shown, each stage thus implemented has its own
pressure pump and crossflow pump 2907, 2909 and 2911 and 2913,
respectively. Nanofiltration stage 423 has a maximum operating
pressure of 35 bar (508 psi), and a crossflow pump maximum rating
of 50 gpm at a maximum of 60 psi in a 750 psi environment. Reverse
osmosis stage 429 has a maximum operating pressure of 70 bar (1015
psi), and a crossflow pump rating of maximum rating of 10 gpm at a
maximum of 45 psi in a 1,200 psi environment. System operating
pressure is regulated through bypass regulators 2914 and 2920.
[0230] At this time, the most economical ready-made nanofiltration
membrane shape is a flat membrane sheet in a spiral wound membrane
element. A spiral wound element consists of multiple membrane
pockets (for example 4-16 pockets), the spiral wound pockets
terminating into a centralized collecting pipe. Special parallel
polypropylene spacers of 80 mil thickness are preferred and
complete the membrane (spiral wound nanofiltration membrane
elements from Nadir with a practical neutral surface voltage (zeta
potential), for example).
[0231] The nanofiltration special spacing materials (spacers) are
especially effective in applications with high suspended solids
(colloidal) concentration. Since the primary purpose of the
nanofiltration in station 101 is to remove all suspended solids
rather than dissolved solids (such as salts), these types of
spacers with their larger spacing between the membrane surface are
preferred. A smaller membrane spacer for other applications could
be use (for example, having 33 mil diamond spacer).
[0232] Alternatively, to maintain maximum processing flexibility at
stage 423, low and ultra-low pressure reverse osmosis membranes
could be used (where total dissolved salts are an issue). If
nanofiltration membranes are employed, crossflow pump 2909 output
flow must be turned down at bypass valve 2915 for a lesser brine to
permeate ratio to achieve a more desirable permeate quality.
[0233] Reverse osmosis and/or HEED assembly buffer tank and at
stages 425 and 431 can be any suitable tank and containment basin
(for example, a three leg tank by SNYDER). Stage 427 (step 13) is
interposed to reduce scalants in reverse osmosis processes.
Bicarbonate (HCO.sub.3) is present in many post production waters
presented for treatment (such as CBM water, for example). Many
produced CBM waters are near saturation in dissolved bicarbonate.
When these waters are concentrated in a reverse osmosis system,
calcium carbonate will be one of the first salts to precipitate.
Calcium Carbonate scaling potential can be estimated using
stability index calculations.
[0234] Prevention of calcium carbonate precipitation in the
nanofiltration or reverse osmosis systems of station 101 is aided
by injection of sulfuric acid at pump 306 into a homogenizing
buffer tank at stage 417 to condition nanofiltration and/or reverse
osmosis feed water. This will convert much of the bicarbonate to
carbonic acid and dissolved carbon dioxide as well as increase the
solubility of calcium carbonate due to the lower pH. In estimating
the acid concentrations for pH adjustment, the rule of thumb is
that lowering the feedwater pH to between 6.0 and 6.5 will reduce
the bicarbonate concentration by about 80%. For most CBM waters and
typical pilot program nanofiltration and/or reverse osmosis
permeate recoveries, an 80% reduction of bicarbonate will be
sufficient to prevent calcium precipitation.
[0235] By inline injection of a fouling and scaling inhibitor (such
as VITECH 3000) at stage 421 into the nanofiltration feed stream,
colloidal and scale crystal growth is slowed, colloidal formation
inhibited, and the crystalline shape of the scale crystal is
modified. By inline injection of a scaling inhibitor (such as
VITECH 4000) at stage 427 into the reverse osmosis feed stream,
scale crystal growth is slowed and crystalline shape is modified.
It should be realized that scaling by other salt types can occur
simultaneously (for instance, BaSO.sub.4). Therefore, it is
necessary for the hybrid dosing to catch the remaining scaling
causing salts with an antiscaling medium. Common scale inhibitors
consist of molecules that contain carboxylic or phosphate
functional groups. Lower molecular weight polyacrylate molecules
contain multiple carboxylic functional groups.
[0236] At reverse osmosis implementation of stage 429, membranes
2903 and 2905 are preferably spiral wound polyamide skin layer
composite membranes with a zeta potential of approximately -7 mV
and a polysulfone support layer and standard 31 mil diamond spacers
(since prefiltered feed water will be used). Optionally, seawater
polyamide membranes with a spacer thickness of 27 mil could be
utilized. The polyamide thin layer membranes are constructed with
an aromatic polyamide extruded onto a less dense polysulfone
substrate. The optional seawater membrane elements use a denser
polyamide membrane layer with better rejection characteristics.
[0237] Polyamide membranes are sensitive to oxidizing agents such
as free chlorine or iodine. This requires that chlorine or iodine
present in the feedwater be removed by a reducing agent (such as
sodium bisulfite in the case of chlorine injected upstream of the
reverse osmosis modules). To avoid fouling in such case, a
non-oxidizing biocide like BUSAN (150 to 1500 ppm) can be
continuously injected in-line with the reverse osmosis feed stream.
This mixture which kills bacteria, fungi and algae is compatible
with the membrane material as well as the other injection chemicals
used.
[0238] A number of parameters can affect reverse osmosis permeate
flowrate at stage 429 (or stage 425 if used there also). These
include water temperature, salt concentration and membrane pressure
as the feed water flows through the system. Since station 101 is
not specifically adapted to a particular water presented for
treatment, stage 429 is preferably configured work within a minimum
and maximum range of 1,000 ppm to 20,000 ppm TDS, as well as a
temperature range of 40.degree. to 80.degree. F. The system's
maximum design pressure is around 1,000 psig.
[0239] Higher pressures result in higher permeate flowrates and
better salt rejection characteristics. Higher pressures also
require more power and can result in higher membrane fouling rates
and reduced membrane life expectancy. These considerations are
important considerations for programming at steps related to
upsizing (to full size plant). In addition, higher pressure
operation may require stainless steel, fiberglass/epoxy or carbon
fiber/epoxy membrane housings and piping material to handle the
higher pressure. To maximize flexibility for different water
treatment applications, station 101 preferably includes reverse
osmosis systems configured for high pressure operating
capabilities.
[0240] Membrane 2903 housings are arranged vertically rather than
horizontally, and all are top fed. This operating geometry provides
gravitational assistance to the high speed crossflow turbulence.
Crossflow (recirculation flow) is provided by pump 2913 and flow
controlled by bypass valve 2919. System pressure is controlled by
pressure regulator 2920. Pressure pump 2911 operates at a maximum
flowrate of 2.65 GPM at a maximum 1,029 psi.
[0241] Station 101 employs high speed gravity assisted geometries
in their system design. Thus, membrane systems are working with an
unconventional high crossflow velocity, and the membrane housings
are geometrically arranged in a vertical top feed position.
Therefore, it allows the feed water crossing the membrane with the
assist of gravity, whereby the chosen array minimizes the pressure
differential across the membrane system. This differential would
otherwise take away from the net driving pressure at the tail end
of the individual membrane system.
[0242] A portion of the concentrate is recycled back to the overall
membrane system feed to increase recovery beyond the 75% it may
have already achieved. For example, by recycling only 1/5 of the
concentrate back to the feed, recovery can be increased to an 80%
permeate recovery. This results into a 20% reduction of disposable
concentrate production. The concentrate recirculation (retentate)
flow rate for the pilot unit operation is provided through the
crossflow pumps 2909 for the nanofiltration at stage 423 and 2913
for the reverse osmosis at stage 429.
[0243] In order to provide the desired high crossflow velocity over
the membranes, and in accord with another aspect of this invention,
separate high flow, low pressure crossflow pumps are utilized.
Since pressure pumps 2907 and 2911 of the membrane system cannot
fulfill these requirements, separate low pressure but high flow
crossflow pumps operating in a high pressure environment with
flowrate adjustment capability are needed. These pumps are
magnetically driven with no seals and are equipped with high
pressure stainless steel housings to contain a feed pressure of up
to 1200 psi. The relatively small, low energy, high pressure feed
pumps provide the system operating pressure. The feed pressure and
flow rate is preferably regulated by a vector drive.
[0244] Through this arrangement, the feed achieves sufficient
pressure through the high pressure feed pumps for membrane
separation. These high flow crossflow pumps provide sufficient
turbulence and hydrodynamic shear to flush down and clean out the
membrane flow channels of contaminated matter to minimize any
fouling/scaling potential of the specific membrane system. The low
operating pressure of the crossflow pump does not create excessive
pressure even when operated at full flow capacity. Crossflow meters
are preferably utilized to measure, control, and obtain optimum
crossflow and crossflow velocity to achieve sufficient turbulence
to minimize fouling/scaling potential. Turbine meters with magnetic
pickups and transmitter/read-out units are preferred. The preferred
pumps here are magnetically driven centrifugal pumps. The high
flowrate is needed to cover a large crossflow rate range. The
flowrate is easily adjustable through a valve controlled
by-pass.
[0245] Turning to FIG. 30, the preferred magnetically driven
centrifugal pump 3001 (used, for example, for pumps 2909 and/or
2913) of this aspect of the invention is illustrated, such pumps
being heretofore commercially unavailable that can operate in a
high pressure environment (over 500 psi for the nanofiltration, and
in excess of 1,000 psi for reverse osmosis). All high pressure
parts are manufactured from compatible nonmagnetic stainless steel
series 316 or 312, 316L or Hastelloy C4 (casing sections 3005, 3013
and 3016, for example). Nonmagnetic stainless steel is required to
contain the high operating system pressure, to offer corrosion
resistance in a chloride rich environment and to allow a magnetic
field transfer, from drive magnet 3007 to magnet capsule 3021, to
facilitate the no touch magnetic coupling process.
[0246] Another novel element of the pump design herein is use of
off-the-shelf plastic low pressure internal pump parts (for
example, impeller 3009, mouth ring 3011, spindle 3015, rear thrust
3018, front thrust 3019 and magnet capsule 3021). Since pump
shavings from plastic impellers have been known to foul the lead
end elements of membrane systems, an optional discharge screen
downstream of the pump is recommended. A chemically resistant
coating such as Ceramic, PVDF, PP, PE, HPE, PTFE or PFA is utilized
to prevent pitting and is applied to the inside of high pressure
pump components.
[0247] The magnetic pump is otherwise of convention design. Ceramic
spindle 3015 is mounted rigidly on one end onto stationary, high
pressure resisting rear casing 3016 which is made from non-magnetic
stainless alloy. Main bearing 3017 rotates on the protruding end of
spindle 3015, bearing 3017 press fitted into magnet capsule 3021
which is counter-rotationally twist-locked onto impeller 3009.
Pointed conical rear thrust 3018 is mounted on impeller 3009 and
limits rearward movement of magnet capsule 3021 and impeller 3009.
Thrust 3018 rides against the front face of stationary spindle 3015
thus limiting the rear thrust. Likewise, front thrust of magnet
capsule 3021 and impeller 3009 is limited by impeller mounted mouth
ring 3011 riding against the front face of stationary front thrust
3019. The feed medium itself provides lubrication between moving
and stationary thrust contact areas.
[0248] In accordance with another aspect of this invention, in-line
degasser and degasser column assemblies 3101 are shown in FIGS. 29
and 31. Assemblies 3101 are specifically adapted for air and/or
CO.sub.2 removal or reduction in the produced membrane permeate
flow stages 423 and 429 in order to improve flow rates and flow
data acquisition in the permeate production process. The design,
use and application of these assemblies are an improvement over
prior art designs and methods. Assemblies 3101 condition flow of
produced permeate by air/gas removal prior to processing through
flow instrumentation and recording devices for the generation of
real time liquid flow data without error producing air or gas
content. Assemblies 3101 are adaptable in any setting where
enhanced flow process stabilization is required in a liquid system
with entrained and unwanted air or gas and where in-line degassing
is needed for flowmeter applications. No packing material is needed
for optimum surface area contact between the water and the air as
is used in conventional tall column forced-draft degassifier
designs.
[0249] Assemblies 3101 include inline degasser 3103 and attached
degasser column 3105, and has no moving parts. Head back pressure
control can be adjustable by height adjustment of elbow 3107
relative to the top of column 3105 (at cap 3109). Visual inspection
of ongoing degassification processes can be monitored through clear
column tube 3111. Ball-valve 3113 controls flow to degasser 3103 of
assembly 3101, flowmeter 3115 following degasser 3103. Gas
supersaturated concentrate flows into the bottom of expansion
chamber 3117 of degasser 3103 providing atmospheric pressure
release through top connected hose 3119. Hose 3119 is connected at
the other end to degasser column 3105.
[0250] Vertical adjustment of column 3105 provides proper
back-head, back-pressure control, the column's horizontal swivel
capability at cantilever arm 3121 providing dead leg free hose
transfer. Head is adjusted to match individual concentrate draw-off
by keeping enough column head on column 3105, which is open to the
atmosphere. As a result, a spilling out of concentrate flow is
avoided. Through controlled release of back-pressure, concentrate
discharge gas pressure is lowered in expansion chamber 3117.
[0251] The in-rushing expanding CO.sub.2 bubbles towards the lower
pressure level of upper expansion chamber outlet 3123. The rising
bubbles accelerate during their ascent due to the simultaneous
decline of available head pressure in assembly 3101. Since the
ascending bubbles are shielded from entering the lower water
transfer openings in pipe riser 3125 by shield 3127, only the
descending, saturated but bubble-free water enters the transfer
openings. The now transformed water from the supersaturated to the
saturated stage is calm enough to allow for meaningful flowmeter
readings and control.
[0252] Flow distributor and discharge equalizer 3201 in accord with
another aspect of this invention is shown in FIG. 32. The method of
use of equalizer 3201 is novelly adapted to use with high speed
crossflow membrane systems operating in a gravity assisted mode.
Equalizer 3201 is hydrodynamically designed for flow direction from
a horizontal entry flow at port 3203 to a vertical flow in housing
3205, and a flow directional change back from a vertical flow to a
horizontal side exit flow to enhance operation of the vertically
mounted high speed membrane systems.
[0253] Flow altering distribution cones 3207 at product tube
extension 3209 provide favorable hydromechanical loading and
unloading for spirally wound membranes by distributing the
in-rushing high crossflow of high operating pressure more evenly
into the leading portion of the vertically arranged membranes.
Since favorable membrane hydromechanics extends useful membrane
life expectancy, cost savings are realized.
[0254] Equalizers 3201 are mounted in place of long sweeping
mounting elbows usually used for top entry and bottom exit of
conventional high speed, vertical membrane system designs (at 3211,
for example, in FIG. 29, other utilization nodes being identifiable
in the drawings). This improved hydrodynamic design adapted for
side entry operation is a practical method for reducing overall
height and footprint requirements of a vertically mounted, high
speed membrane system.
[0255] In accordance with another aspect of this invention, a first
embodiment of a high frequency membrane separation apparatus and
method utilizable with membrane systems of this invention is shown
in FIGS. 33a and 33b. This invention relates to apparatus and
methods for fluid filtering utilizing membrane separation (for
example nanofiltration and/or reverse osmosis filtration) that
combines vibratory shear techniques with adjustable crossflow
techniques. This and further embodiments of the high frequency
membrane separation apparatus and methods (set forth hereinafter)
are particularly well adapted to treatment stages 419, 423, 429
and/or 433 when membrane treatment options are applied (generically
referred to hereinafter as membrane treatment systems).
[0256] High frequency membrane separation herein refers to
vibrating, oscillatory motion of the membrane support structure.
Vibration direction is perpendicular to the floor of station 101
for gravity assisted membrane separation systems. The vibration
curve is preferably a regular curve, which corresponds
mathematically to a zero centered sine or cosine, a sinusoidal or
simple harmonic. The amplitude is preferably steady and frequency
high.
[0257] This hybrid does not depend solely on vibratory induced
shearing forces to prevent fouling and thus does not require total
shut down of the membrane separation process during preventive
maintenance on the vibrators. The shear wave produced by axial
vertical membrane vibration causes solids and foulants to be lifted
off membrane surfaces and remixed with retentate flowing through
the parallel or tunnel spacer or other specially designed spacers
of spirally wound elements or through flow channels of tubular or
capillar membrane elements. Movement continuity is maintained
through the adjustable crossflow, reducing further additional
membrane fouling tendency.
[0258] This hybrid approach using adjustable crossflow and high
shear processing exposes membrane surfaces for maximum flux (volume
of permeate per unit area and time) that is typically higher than
the flux of conventional vibratory membrane technology alone. In
the conventional vibratory membrane design, each membrane module
requires its own vibratory energy source. Only a single vibratory
engine 3303 is utilized for a multi-membrane module design herein
(up to thirty-two 2.5'', sixteen 4'' or eight 8'' membrane
modules).
[0259] To suit operating environments such as those at station 101,
where height restrictions and/or leveling problems are encountered,
high frequency membrane separation apparatus of this invention can
be operated at an incline using center pivot 3304 for adjustment of
swivel framework 3305 (from standard vertical position to a maximum
15.degree. incline orientation) in swivel support 3306. Unlike
other vibratory membrane separation technology which employs
horizontal vibratory torsional motion in the axis plane of abscissa
(x), and which require use of proprietary one source only custom
membrane modules, this approach is more flexible. Readily
available, and thus less costly, conventional membrane modules can
be used, and mounting of membrane modules in a vertical flow
gravity assisted position with adjustable crossflow operation is
accommodated.
[0260] This embodiment of the high frequency membrane separation
apparatus uses twin motors connected at shaft/eccentric and weight
assemblies 3307 and 3309 of the motors in vibratory engine 3303 to
provide shear enhanced fouling reducing membrane separation (these
vibrator motors are well known structures). The motors are
preferably 3-phase 1800-3600 RPM induction motors delivering high
speed synchronized centrifugal force, one motor rotating
shaft/eccentric and weight 3307 counter-clockwise and the other
rotating shaft/eccentric and weight 3309 in a clockwise
direction.
[0261] The vibrator motors are capable of producing net centrifugal
forces that change direction in space as the motor rotates. Such a
force acts upward at one instant and downward a half-rotation
later, thus producing a force that acts sinusoidal at a frequency
that corresponds to shaft/eccentric/weight assemblies 3307/3309
rotation.
[0262] Adjustable eccentric weight provides variable force output
(from 0% to 100%) at a synchronized mode of operation (i.e., the
adjustable weights are aligned with each other at 90.degree. for
clockwise rotation and 270.degree. for counter-clockwise rotation).
A vibratory high-speed linear motion through center of gravity thus
impacts swivel framework 3305 having the vibrating motors mounted
on the inside thereof and the membrane modules mounted on the
outside thereof.
[0263] Support box frame structure 3310 is preferably square tubing
2''.times.2'' with a 1/8'' wall. Frame structure 3310 carries
membrane modules (hereinafter 3311, generally applied, for example,
to modules 2901 or 2903/2905 of FIG. 29 or other membrane modules
disclosed herein and related to the various nanofiltration and
reverse osmosis options) and includes frame uprights 3312 mounted
via rubber dampeners 3313 (preferably eight) at swivel framework
3305 (one upright per corner of the support structure). Swivel
frame uprights 3315 of support 3306 are preferably made from
fabricated 1/4'' steel material, and are connected to seismic
absorbing mass at fabricated steel base frame 3317. Base frame 3317
is preferably at least partially filled with concrete to add
mass.
[0264] Two springs 3319 are located in-line at the top of support
structure box frame 3310 (supporting panel structure not shown) and
between horizontal top frame members 3321 of the open swivel
framework 3305. Dampeners 3323 are located adjacent to bottom frame
member 3325 of swivel framework 3305. As compared to conventional
springs, urethane springs/dampeners are preferred for their high
load-carrying capability, longer life, abrasion resistance, low
noise, and vibration damping and shock absorbency.
[0265] The springs themselves are cylindrical, and four connecting
bolts 3327 fasten support structure 3310 to swivel framework 3305.
The fine-threaded connecting bolts allow for vibratory amplitude
adjustment in a range up to about 1''. If combined with
conventional coil springs, the vibratory amplitude adjustment range
increases up to 1.5''. Together with the adjustable frequency drive
(or inverter drive), customization of axial vibratory linear motion
for shear enhanced fouling reducing membrane separation is
accommodated.
[0266] A second embodiment of the high frequency membrane
separation apparatus and methods of this invention is shown in
FIGS. 34 through 38. In the embodiment shown in FIG. 34, vibration
is hydrodynamically controlled. This embodiment is specially
applicable whenever a homogen disperse fluid substance with a lower
concentration polarization layer has to be treated--for instance,
organic and inorganic colloidal solution as well as fine disperse
suspensions and higher concentrations of salt solutions (TDS
1,000-50,000 mg/L). Since high shear rates are not required in high
frequency membrane separation apparatus 3401, apparatus 3401 can be
configured to operated at a lower amplitude. System 3403 can
operate efficiently at a lower amplitude.
[0267] Vibratory impulse energy is provided through the primary
feed pump (for example, pumps 2907/2911 as shown in FIG. 29), no
secondary vibratory energy source is required. Furthermore, only
the membrane, fluid column (preferably pre-filtered as taught
herein, generally represented at 3404) and some associated internal
components of apparatus 3401 are vibrated (not the entire unit
including support mass). One feed pump 2907/2911 can serve one or
many modules in parallel feed array.
[0268] In combination with heretofore described crossflow
characteristics, hydrodynamic vibration herein provides axial
vibration of amplitude "Y" to enhance the sinusoidal flow pattern
between transverse spacer rods 3801 in membrane media 3802 (see
FIG. 38). Vibration amplitude is controlled through stroke
adjustment. The system operates with low vibratory energy waves
which are scaled to provide effective agitation. Axial vibration
with a maximum amplitude Y of only about 2 mm for a spirally wound
membrane is sufficient to maintain proper permeate continuity.
Apparatus 3401 provides sinusoidal meandering turbulent cleaning
action by high frequency vibration up to 180 Hz in a tangential
direction to the surface of the membranes (see FIG. 38).
[0269] To effect the benefits of hybrid apparatus 3401 membrane
element 3405 is oscillated within the membrane housing 3407 (see
FIGS. 35 through 37). The bulk stream containing the returned
suspended particles between the membrane leaves of spirally wound
membrane elements (generally at 3803 in FIG. 38), and in the flow
channels of tubular and/or capillary membrane elements, is
continuously flushed out of the membrane module by means of the
gravity assisted low crossflow. Since apparatus 3401 does not
depend on crossflow induced turbulence, feed of a homogen fluid
substance with a lower concentration polarization layer can be
concentrated at a higher level.
[0270] Crossflow pressure can be maintained in a low range between
35 and 140 kPa (utilizing crossflow pump 2902/2913, for example)
thus producing an adjustable low crossflow velocity in the range of
0.075 to 1 m/s and requiring low operating energy. Sufficiency of
turbulence for anti-fouling/scaling is maintained by high frequency
of the vibration. Produced are low vibratory energy waves scaled to
provide a nonstagnant membrane area environment with effective
sinusoidal meandering turbulence to the boundary layer 3805 area,
settling of suspended particles thus inhibited.
[0271] Feed activated hydrodynamic impulse system 3501 is best
illustrated in FIGS. 35 through 37. A pulsating high pressure water
jet is receive from plunger pump 2907/2911 through inlet port 3503
through lower retainer ring 3504 and feed ring-room housing 3505 at
lower section 3506. Housing 3407 holding filter module 3405 is
ported as required for feed input and concentrate and permeate
output and is constructed accordingly. Upper section 3601 (FIG. 36)
includes permeate discharge connector 3603, upper retainer plate
3605, spring rings 3606, bolt retainer plate 3607, spring
adjustment plate 3609 return spring 3611 and lantern ring 3613.
Variously sized O-rings seals 3615 seal the unit. Membrane coupling
3617 couples connector 3603 to membrane 3405.
[0272] Lower section 3506 (FIG. 37) further includes permeate tube
plug 3703, ring piston 3705, retentate discharge connector 3707,
and spring rings 3709 and 3711. Again, various sized o-rings 3713
seal the apparatus. As can be appreciated the pulsating jet of
received through port 3505 vibrates module 3405 at ring piston 3705
at the rate of pulsation. Reciprocation is limited and maintained
by spring 3611 operating against ring 3613 (held in adjustment by
adjustment plate 3609).
[0273] Self contained, vibratory spring, seal and transfer conduit
apparatus and methods, in accord with yet another aspect of this
invention, are illustrated in FIGS. 39 and 40. The self contained,
vibratory spring, seal and transfer conduit apparatus and methods
of this invention provide a flexible sealing connection between an
oscillating and a stationary object by means of a fluid conveying
elastomeric conduit connection. The flexible fluid conveying
conduit is equipped with nonflexing end connectors to provide
motionless sealing surfaces for the associated o-ring seals which
are housed in the respective objects. As a result, positive
nonreciprocating sealing in a dynamic operating environment is
provided.
[0274] Self contained apparatus 3901 is adapted for (but not
limited to) use with vibrating membrane technology of the type
shown herein in FIG. 35 (and numbers therein common to both
embodiments are carried forward). Apparatus 3901 is preloaded under
tension by a polyurethane based permeate transfer conduit 4003
(also referred to herein as polyurethane spring conduit 4003). The
material used has a durometer of about 60 A and has high rebound
values (greater than 65%) sufficient to withstand high frequency
vibrations. The materials is selected to have high load bearing
properties in both tension and compression). All machine elements
thus remain in alignment and remain stationary (relative to one
another) thereby preserving sealing surfaces while the vibratory
load is operating.
[0275] Springs (preferably Belleville or disc springs) 4005
generate a portion of the compressive force counter reacting the
tension load of polyurethane spring conduit 4003. Pre-load
retainers 4007 preferably stainless steel retainer rings or spring
clips)contain and secure preload, connecting urethane spring
conduit 4003 with the upper and lower load guides 4009. Springs
4005 are held between upper and lower load guides 4009 and center
load guides 4011, load transfer spacer 4013 spanning center guides
4011 spacing the two spring columns (formed by a spring 4005 and
one each of load guides 4009 and 4013). This arrangement equally
distributes the low value tension and compression loads.
[0276] Spring 4015 further supports polyurethane spring conduit
4003. Conduit 4003 is mounted at the upper end with a modified
plate 4016, abutting modified permeate discharge connector 4004,
and at the lower end to a modified lantern ring 4017. Load transfer
spacer 4013 has a length selected so that maximum urethane spring
conduit 4003 deflection is less than 2%. Urethane spring
manufacturers suggest a maximum deflection of 25% and a maximum
cycle rate of 700 cycles per hour for intermittent operation. For
continuous operations and a maximum deflection of 15%, a maximum
cycle rate of 12,000 cycles per hour is suggested. Because
apparatus such as apparatus 3901 has a cycle rate of between
216,000 and 648,000 cycles per hour, the deflection percentage
needs to be significantly reduced.
[0277] Apparatus 3901 provides wear and leak-free operation for
permeate fluid transfer between oscillating membrane element 3405
and its stationary housing 3407 components, thus effectively
avoiding contamination of the produced permeate with feed water.
Apparatus 3901 accommodates either high frequency membrane
separation housing designs (side port entry and the top port entry)
and serves as a return spring for apparatus 3401 as well as a
permeate transfer conduit and seal unit. Modular design
accommodates ease of maintenance.
[0278] On the lower side of apparatus 3901, lower spring 4005
column oscillates simultaneously with the module 3405, while at the
upper side of apparatus 3901 upper spring 4005 column remains
steadier so that the connecting end of conduit 4003 remains
motionless in its sealing seat 4019. This is due to the return
spring pressure acting upon the upper retainer which keeps the
upper male connecting end securely in its sealing seat.
[0279] In accordance with yet another aspect of this invention,
FIGS. 41 and 42 illustrate a high shear and high amplitude internal
membrane separation apparatus and methods. This invention relates
to permeate continuity in water treatment processes. More
particularly, the purpose of this aspect of the invention is to
achieve high shear in such processes to increase permeate
continuity while treating high load of colloidal and slimy matter
(polysaccharide, etc.) in treatment station feed water.
[0280] Apparatus 4101 illustrated in FIG. 41 offers high shear
operation for internally vibrating membrane separation systems of
the types heretofore disclosed. This high shear option is provided
by means of a high vibration amplitude in the range of 1/32'' to
3/8''. However, such high amplitude vibration could damage membrane
element 3405. Thus, in accord with this invention, an
all-surrounding membrane support tube 4103 with upper and lower
connecting end pieces 4105 and 4107 which are rigidly coupled and
locked to support tube 4103 by split tongue and groove rings 4109
are provided, thus converting membrane element 3405 into membrane
cartridge 4111 having element 3405 therein. Membrane cartridge 4111
provides a backlash free, non-load bearing and non-force
transmitting, hardened operating environment for membrane element
3405.
[0281] End pieces 4105 and 4107 also provide means for membrane
fluid transfer. Upper end piece 4105 has two conduits 4113 for
crossflow feed influent and 4115 for produced permeate effluent.
Lower end piece 4107 has multiple inclined conduits 4117 (at least
four conduits for smaller membranes) all merging into large
retentate effluent conduit 4119 of venturi nozzle 4121. Nozzle 4121
has an outside cone angle of about 21.degree. to support venturi
function and enhance rapid transfer of the pulsating, make up feed
flow at elevated operating frequencies. High pressure vibrating
pulsating feed input 4123 through lower flange and injector body
assembly 4124 is positioned to operate against surface 4125 of
lower end piece 4107 to vibrate cartridge 4111.
[0282] Overall, a containment housing 4127 is welded to transfer
flange assemblies 4129 (upper) and outer flange 4130 of assembly
4124, the lower flange assembly bolted together by bolt and nut
sets 4131 through lower inner flange 4132 and outer flange 4130 of
assembly 4124. Upper flange assembly is bolted together with bolt
and nut sets 4133 having recoil springs 4135 thereover for recoil
adjustment. Safety guard 4137 is mounted at the top of apparatus
4101 and includes a window for on-site amplitude inspection.
[0283] The structural integrity of the membrane element 3405 needs
to be strong enough to sustain its own vibratory mass acceleration
forces within its hardened enclosure. To provide maximum structural
membrane element strength, the preferred spirally-wound membrane
element design for all high frequency membrane separation
applications in high shear mode includes fiberglassed outside for
holding element 3405 together. However, amplitudes greater than
3/8'' are not recommended for the spirally-wound membrane elements
under any circumstances since adhesive membrane joints fatigue
prematurely at higher operating frequencies (60 Hz).
[0284] Apparatus 4101 allows operation of vibratory membrane
implementations at higher shear at moderate frequency (20 to 60
Hz). Membrane cartridge 4111 is relatively light and vibrates
internally at an adjustable up to a relatively high frequency
within housing 4127 (rather than vibrating the entire heavy
membrane module as is common in conventional vibratory membrane
separation processes).
[0285] A primary application for this high shear option for high
frequency membrane separation systems is the effluent treatment of
dewatered electrocoagulation sludge. This is an important treatment
step whenever a required electrocoagulation process generates
sludge and the produced sludge requires dewatering prior to
disposal. Any other application where an elevated shear energy
requirement for treatment of a specific feed water is diagnosed
would benefit from use of apparatus 4101.
[0286] A secondary application for this high shear option exists
where electrocoagulation pre-treatment is abandoned in favor of
standard nanofiltration treatment. This will produce a concentrate
having colloidal loading too high for standard low shear high
frequency membrane separation processes. Yet another application
occasioned in any circumstance where limited disposal options are
present in extreme high flow yield (high concentration factor)
treatment setting.
[0287] End pieces 4105 and 4107 are preferably machined out of any
suitable material such as metal alloys or engineering plastic
materials (selected to keep the vibratory mass low). To minimize an
unbalanced, one-sided, membrane feed flow channeling,
antichanneling flow distribution plug 4139 having splash dome 4141
blocks direct throughflow and guides the feed flow into ring room
flow distribution channel 4143 defined at end piece 4105. Splash
dome plug 4139 rests on a shoulder in the lower section of feed
conduit 4113 and is secured in its upper position by stainless
steel retainer ring 4142. A flared fluid transfer opening from ring
room 4143 faces towards the anti-telescoping device at the lead end
of membrane element 3405.
[0288] Step bore 4145 in end piece 4105 seals (at o-ring 4147) the
upper end of permeate collection tube 4149. The outside of upper
end piece 4105 includes groove structures, the first to receive
upper reciprocating groove ring seal 4151 to seal the upper portion
of membrane cartridge 4111. A second high and shallow groove 4153
receives the overlapping split tongue ring 4109 (connectable at its
other end in groove 4155 of tube 4103. The split tongue ring halves
can be held together by dual spring rings or other suitable means.
O-ring 4157 seal upper end piece 4105 and support tube 4103.
[0289] To take up axial slack and minimize movement of membrane
element 3405 within its all-surrounding enclosure, shims can be
added to flow distribution and screen plate 4159 sandwiched between
upper end piece 4105 and the anti-telescoping device at the lead
end of membrane element 3405. (and where applicable, at the
permeate collection tube). Membrane element backlash is thus
virtually eliminated.
[0290] Plate 4159 provides the necessary pressure drop for proper
crossflow feed distribution around the feed ring room. In
conjunction with anti channeling flow distribution plug 4139, plate
4159 minimizes localized feed channeling, thus utilizing more
efficiently the available membrane area for diffusive fluid
transfer. Plate 4159 also acts as a crossflow pump discharge filter
screen to catch any particles and foreign objects.
[0291] Support tube 4103 can be made from a thin-walled metal alloy
a heavier walled, suitable plastic material in order to reduce the
vibratory mass. Support tube 4103 is grooved at it bottom end (at
4155) to provide a connection sites for tongue and groove ring 4109
thereat. U-cup seal gasket 4161 is placed around the outside (in a
concentrate seal holder 4162) of the lead end of the membrane
element 3405. This gasket seals membrane element 3405 to external
support tube 4103 and prevents the crossflow feed influent from
bypassing the membrane element.
[0292] Downstream, membrane element 3405 is equipped with an
anti-telescoping device that is connected to lower end piece 4107
by means of the extended lower end of its permeate collection tube
4162. Tube 4162 is sealed at o-ring 4163 at lower end piece 4107.
Lower end piece 4107 itself is rigidly coupled and sealed to
support tube 4103 in the same manner as upper end piece 4105. The
top face of lower end piece 4107 is equipped with a tapered,
shallow ring groove 4165. Groove 4165 collects and distributes
concentrate/retentate fluid through multiple inclined fluid
transfer conduits 4117 which are distributed around groove
4165.
[0293] Protruding venturi nozzle 4121, is fitted in inlet chamber
4166 which is defined by injector body 4167 of assembly 4124
protruding into lower end piece 4107 leaving a small ring room 4169
adjacent surface 4145 of end piece 4107 for the distribution of the
high pressure, pulsating make up feed flow. Venturi nozzle 4121 has
an effective sealing length equivalent to the maximum operating
amplitude.
[0294] End piece 4107 has a dual purpose concentric guide shroud
4171 providing a close fit concentricity between the axially
vibrating lower end piece 4107 and non-vibrating injector body
4167. Shroud 4171 defines a reasonable operating clearance between
end piece 4107 and external housing 4127 to ensure proper operation
of reciprocating seal 4172 sealing housing 4127 and vibrating
membrane cartridge 4111 from potential fluid loss. Shroud 4171 also
provides impact surface 4173 contacting amplitude regulating impact
ring 4175. Ring 4175 is preferably made from polyether-based
urethane (60 on the Shore A scale), providing shock deadening. Ring
4175 is configured and positioned for highly resilient operation
providing quick recovery in high-frequency vibration applications
(rebound values from 50 to 70%). Vibration amplitude ranges can be
regulated by ring height selection. An increase in ring height
increases the volume of the distribution ring room 4169 while
reducing the effective height of the cylindrical shaped section of
nozzle 4121.
[0295] In operation, the unchanged volume of the displacement
stroke of high pressure piston pump (2907 or 2911, for example, in
FIG. 29) first fills the volume of ring room 4169 with feed liquid
before it starts to initiate an axial, upward movement of membrane
cartridge 4111. Once the cartridge travel upwards and exceeds the
reduced height of the outer diameter of nozzle 4121, a fluid
transfer passage around nozzle 4121 (from ring room 4169 to chamber
4166) opens and passes the liquid which then flows by the
21.degree. cone-shaped end of nozzle 4121 of lower end piece 4107.
Consequently, the feed flow through this transfer passage is
entrained and carried along by the venturi effect of the
concentrate/retentate discharge and is subject to the priming
suction of the crossflow recirculation pump (2909 or 2913, for
example, in FIG. 29).
[0296] Injector body 4167 is also preferably a unitary structure,
machined, for example, from either suitable metallic alloys or
plastic material. Injector body 4167 has large conduit 4177 and
smaller conduit 4179, conduit 4177 for transfer of concentrated
retentate and the pulsating, make up feed influent to crossflow
recirculation pump as discussed hereinabove. Conduit 4179 is the
input for the vibration inducing feed. Injector body 4167 is sealed
at outer housing 4127 with o-ring 4181. Camber 4166 tapers down at
conduit 4177 to funnel the flow into recirculation suction
connector pipe 4183 maintained through inner lower flange 4132.
[0297] Injector body 4167 is positioned and kept in place inside
external housing 4127 by flange 4132. The weldment of flange 4130
and housing 4127 could be replaced by an integral structure such as
a pipe spool. An upper impact and buffering ring 4185 (made from a
polyurethane material) is located between upper end piece 4105 and
upper inner flange 4186 of flange assembly 4129 (the weldment of
flange 4187 of assembly 4129 to housing 4127 could also be replaced
by an integral structure such as a pipe spool).
[0298] While not preferred, a potentially useful alternative draw
off arrangement for apparatus 4101 as illustrated in FIG. 42 could
be utilized. This arrangement provides secondary retentate conduit
4201 in conduit 4183 and through injector body 4167 and chamber
4166 defined by lower end piece 4107 so that its inlet 4203 resides
above venturi nozzle 4121 in conduit 4119. In this way draw off
received through cartridge 4111 can be at least partially
segregated from mixed retentate and feed received during operations
from ring room 4169.
[0299] In accordance with another aspect of this invention, FIGS.
43 through 45 illustrate an oscillatory crossflow membrane
separation apparatus and methods. The object of the apparatus and
methods of this aspect of the invention is to achieve adequate
shear in treatment of contaminated water to increase permeate
continuity for feedwater having moderate colloidal loading. The
apparatus employs vibratory membrane treatment without moving
sensitive membrane elements 3405 or modules 3311 and associated
components. This minimizes energy requirements while simultaneously
increasing membrane longevity. Standard membrane elements 3405 and
standard modules/housings 3311 may be used.
[0300] As previously discussed, thickness of the membrane boundary
layer is affected by the permeate flux rate. However, oscillatory
crossflow shear forces, together with a spacer introduced
homogenization effect, reduces the size of the boundary layer by
pulling-suspended particles back. This, in turn, keeps them from
settling and returns the particles to the bulk stream. The bulk
stream contains the returned particles between the membrane
leaves.
[0301] In apparatus/system 4301 oscillatory shear forces are
provided by the pulsing crossflow medium itself, oscillatory
crossflow pulsations generated by modified piston or diaphragm pump
4303 (for example, pumps from SPECK, WANNER, CAT, DANFOSS (Nessie),
or others). Pump modification consists of the removal of the
particular pump suction and discharge check valves.
[0302] This valveless pump 4303 provides no true pumping. Only an
up and down, pulsating fluid column is generated by the valveless
pump. Since valveless pump 4303 in apparatus 4301 does not function
as an operational pump, it will be referred to hereinafter as a
fluid oscillator. Since oscillator 4303 does not have to produce a
high pressure gradient, its operating energy requirement is very
low. Oscillation amplitude (height of the fluid column) depends on
the relationship between the combined membrane flow channel
displacement volume, geometric displacement volume of fluid column
oscillator 4303, and membrane element 3405 length.
[0303] Crossflow movement of the oscillating fluid column over
membrane element 3405 is provided pump 2909/2913, for example.
Valve controlled bypass 4305 is located between the discharge from
crossflow recirculation pump 2909/2913 and after the discharge end
of oscillator 4303 for purposes of bypassing oscillator 4303 and/or
fine tuning the pulsation effect. System feed pressure is provided
by high pressure pump 2907/2911.
[0304] Feed pressure pump 2907/2911 provides the applied membrane
pressure after adjusting for the permeate pressure and, if
applicable, for the osmotic pressure. Crossflow pump 2909/2913
provides a stream of prefiltered (as heretofore discussed and
indicated generally herein at 4307) feed fluid passing over the
surface of membrane element 3405 which flows perpendicular to the
permeate stream. Oscillator 4303 provides the pulsating shear force
effect to the combined flow volume of the other two pumps and
operates in series with pump 2907/2911.
[0305] The primary application for apparatus 4301 and related
methods is for membrane systems having small, combined membrane
flow-channel displacement volume, wherein, despite a relatively
small geometric displacement volume of fluid column oscillator
4303, an adequate oscillation amplitude height producing an
effective shear action to minimize the thickness of the membrane
boundary layer is produced. The methods and apparatus 4301 for
oscillatory crossflow membrane separation can be applied whenever a
crossflow, combined with a reduced permeate flux, is otherwise
insufficient to reduce the boundary layer thickness. Upgrade and
maintenance situations can make particularly effective use of
apparatus 4301. Apparatus 4301 would also be useful in treatment
settings where the medium to be treated shows a high scale
formation potential caused by high concentration of dissolved
salts.
[0306] FIG. 44 shows an operating principle variation of the system
shown in FIG. 43. In this embodiment, oscillator 4303 works against
pump 2907/2911. This embodiment is particularly useful if the
medium to be treated shows a high fouling potential caused by
suspended solids of colloidal matter and organics. FIG. 45 shows
yet another variation of the system shown in FIG. 43. Fluid column
oscillation is provided by double-acting cylinder system 4501 with
a single piston. The piston is powered by an electrical crankshaft
drive. The double-acting cylinder system enhances the fluid column
oscillation over the entire membrane.
[0307] In operation, during a piston upstroke in oscillator
4303/4501, the fluid column within the leaves of membrane element
3405 is accelerated upwards. The upward movement starting at the
discharge end of membrane element 3405. The pneumatic accumulator
of a standard membrane module 3311 acts as a hydraulic balancer in
the system of this aspect of the invention. Air pressure in the
accumulator acts as a weight for raising the piston by pushing the
stand pipe's fluid column against the bottom side (rod side) of the
piston thus assisting the column's upward movement over the entire
membrane length and minimizing slip and localized hydroshock.
Piston friction is reduced allowing for high oscillating frequency
operation.
[0308] During a piston downstroke in oscillator 4303/4501, the
fluid column within the leaves of membrane element 3405 is
accelerated downward, the downward movement starting at the
discharge end of the membrane. The momentary void at the lead end
of membrane element 3405 is augmented by the stored energized
volume from the hydropneumatic accumulator, thus providing an
uninterrupted downward movement of the fluid column over the entire
membrane length and minimizing slip and localized cavitation.
[0309] The pneumatic accumulator of module 3311 also serves as a
water hammer and surge pressure absorber (shock dampener). The
internal hydromechanical shock vibrations introduced by the
oscillator 4303/4501 could cause damages to membrane element 3405.
The accumulator dampens these hydromechanical shocks without
reducing significantly the adequacy of hydromechanical shear to the
boundary thickness layer of element 3405.
[0310] In general, apparatus 4301 works with a low crossflow
velocity. In order to secure a reversal in shear direction and
produce a useful shear velocity, the crossflow velocity must be
lower than the fluid column oscillation velocity. The fluid column
up-stroke works against the downward directed crossflow. The
oscillatory axial crossflow membrane separation apparatus and
method of FIGS. 43 through 45, when compared to non-oscillating
conventional crossflow membrane systems operating at a standard
crossflow velocity of 1 m/s, reveals that these new oscillatory
apparatus produce higher shear rates by a magnitude due to motional
fluid acceleration. The oscillatory crossflow membrane separation
method of this invention produces approximately five times greater
a shear rate with the up-stroke, and approximately 14 times greater
a shear rate with the down-stroke oscillation than the conventional
crossflow membrane separation systems.
[0311] Turning now to FIGS. 46 through 48, post-treatment stage
435, bio-monitoring stage 437 and collection and return stage 439
will be described. As shown in FIG. 47, post-treatment stage 435
includes treatment apparatus/options 4601, 4603, 4605 and 4607.
Apparatus 4601 provides an activated carbon filter 4608 for gas
absorption. Valve 4609 allows bypass of this option (valves 4611
and 4613 allow other options to be bypassed).
[0312] A dolomite/marble filter for sodium absorption ratio (SAR)
compensation is utilized at stage 4603. Reverse osmosis membrane
treatment applied at station 101 of this invention removes up to
99% of the sodium and almost all of the calcium and magnesium ions
in the treatment flow, and the produced reverse osmosis permeate
may have an elevated SAR value. This may be unacceptable if the
permeate is designated for surface discharge, so apparatus 4603
reintroduces SAR lowering ions.
[0313] Tank 4615 (a 300 gallon Snyder Horizontal Leg Tank, for
example) is filled 3/4 full with crushed white marble split 4617
into which produced permeate is introduced through pipe 4619 at the
bottom of one end of the tank. The permeate exits tank 4615 at the
top of the tank at its other end. The permeate with the residual
CO.sub.2 gas and pH around 6 will leach calcium ions out of the
marble, whereby the pH will be increased to about 7.
[0314] An alternative means for SAR adjustment is by inline dosing
with milk of lime. For inline mixing of milk of lime with treatment
water a multi-stage static KOMAX mixer would be sufficient. The
required amount of Ca(OH).sub.2 or more specific Ca depends on the
residual Ca content in the treatment water and the desired sodium
absorption ratio. When lime requirements are high, QuickLime CaO
can be formulated in a lime slaker to convert it to the hydrated
Lime Ca(OH).sub.2. An injection pump or pumps then deliver the
solution into a 200 gpm slipstream, consisting of a blend of raw
and treated water, which is mixed with Ca(OH).sub.2. Downstream,
the calcium enriched slipstream is blended with the residual
discharge stream in a static inline KOMAX mixer prior to
discharge.
[0315] Ultraviolet radiation treatment apparatus 4605 employs 254
nm UV light. The 254 nm UV is employed for microbial
decontamination or disinfection at bulb 4623. The most advanced
theory of bacterial action of UV suggests that photochemical
alteration of deoxyribonucleic acid (DNA) hinders the bacteria or
microbial contaminants from reproduction (photochemical birth
control). Although the bacteria or microbial contaminants are not
killed, if they cannot reproduce, then their potential impact is
dramatically reduced. The dosage required to inhibit population
growth by 100% for a selected target organism depends on the
specific organism. For a specific organism, a dosage rate is
established through experimentation, since the dosage varies widely
between different organisms. Therefore, initial treatment analysis
on the subject treatment water includes means for determining the
kind of organisms present.
[0316] The UV treatment can also be employed in the first or second
pre-treatment stage herein (if the turbidity of the feed water is
very low--less than 2 nephelometric turbity units) in three
potential applications: for continuous sanitization of the feed
water; using a 185 nm bulb, for reducing the total organic carbon
of the feed water; and, in case of chlorination, for removing free
chlorine, chloramines or trihalomethanes from feed water.
[0317] Apparatus 4607 is shown in FIG. 47. Apparatus 47 provide
membrane aeration and O.sub.2 utilizing ODE techniques discussed
hereinabove. The apparatus includes microfiltration cartridge 4701
receiving air from blower 4703 and feed from UV apparatus 4605.
Outflow from cartridge 4703 is received at bubble reactor 4705, the
outflow from which is received at biomotoring stage 437 before
receipt at concentrate collection and effluent return stage 439
(FIG. 48).
[0318] FIG. 49 shows one typical circuitry of primary unit power
control and routing at station 101. The system is typical of such
installations, including other installations in station 101, and
includes system lighting and circuit breaker panel 4901, service
disconnect 4902 and power distribution bridge 4903. Station systems
can be established on panel 4901 at headers 4907 (including that
shown in this FIG. 49, established at header panel 4907').
[0319] Various circuits for pump operating systems and controls are
shown for a first water treatment grouping, including edge filter
pump circuit 4909, aerator pump circuit 4911, supply pump circuit
4913, return and transfer pump circuit 4915, and homogenizing pump
circuit 4917. Primary power to supply and return/transfer pumps
4919 and 4921, respectively, as well as to station compressor 4923
and vent blower 4925 and the various circuits is connected through
bridge 4903. The other systems in station 101 follow a similar
wiring logic. Communications and computing systems should be
isolated to assure their integrity.
[0320] In accord with yet another aspect of this invention,
improved spacers for membrane elements of axial vibratory membrane
separation modules are shown in FIGS. 50 through 53. These spacers
combine the known art of parallel spacer technology with the known
art of diamond spacer technology in a novel spacer design. Parallel
spacers require a higher energy gradient to generate turbulence
than diamond spacers but have no stagnant areas. Due to a more
favorable flow channel arrangement, effective membrane flushing is
provided by parallel spacers. As a result, concentration
polarization is avoided. On the other hand, diamond spacers require
a lesser energy gradient to generate turbulence due to the
obstructed, flow-altering, diamond-shaped design, but have a less
favorable flow channel arrangement with stagnant areas. These
stagnant areas are prone to concentration polarization.
[0321] The spacer embodiments 5001, 5101, 5201 and 5301 shown in
FIGS. 50 through 53 all provide turbulence due to an obstructive,
flow-altering, inner layer 5003/5103/5203/5303 of spacious material
(suitable fabric materials, for example) between outer support
structure (rods, for example) 5005/5105/5205/5305, thus reducing
the energy gradient needed to generate turbulence. Outer support
structure 5005/5105/5205/5305 on both sides of inner layer
5003/5103/5203/5303 provides enhanced flow channel clearance so
that generated turbulence may effectively reduce the thickness of
the boundary layer. This avoids concentration polarization. These
spacers are particularly well adapted to the axial vibratory
membrane separation treatment apparatus disclosed hereinabove, and
can be employed in both hydraulic pressure-driven membrane
separation apparatus and osmotic pressure-driven membrane
separation apparatus associated with forward osmosis processes. The
spacers shown in the FIGURES are all bonded spacers utilizing known
bonding techniques.
[0322] As to the different embodiments, embodiment 5001 shown in
FIGS. 50a through 50c utilizes flow-altering, inner layer 5003 of
spacious woven material with a symmetrically opposing outer support
structure 5005. Embodiment 5101 of FIGS. 51a and 51b utilizes
flow-altering, inner layer 5103 of spacious woven material with a
symmetrically offset outer support structure 5105. Embodiment 5201
of FIGS. 52a through 52c utilizes flow-altering, inner layer 5203
of spacious non-woven material with a symmetrically opposing outer
support structure 5205. Embodiment 5301 of FIG. 53 utilizes
flow-altering, inner layer 5303 of spacious non-woven material with
a symmetrically offset, outer support structure 5305.
[0323] In accord with still another aspect of this invention, FIGS.
54 through 56 illustrate apparatus 5401, an assembly for treatment
of biological wastewater from station 101 utilizing a rotating
biological contactor. Apparatus 5401 may be used as an additional
pre-treatment step to remove contaminants such as emulsified
oil/grease, anaerobic iron accepting bacteria, as well as trace
amounts of dissolved iron, manganese and methane gas from the
influent feed water stream.
[0324] The goal of all biological wastewater treatment systems is
to remove the non-settling solids and the dissolved organic load
from the wastewater by using microbial populations. The
microorganisms used are responsible for the degradation of organic
matter and the stabilization of organic wastes. The station of this
invention may use aerobic microorganisms (i.e., microorganisms that
require oxygen for their metabolism). These microorganisms use the
organic content, including anaerobic iron accepting bacteria, of
the wastewater as an energy source to grow.
[0325] The specific biological medium used herein consists of
genetically altered aerobic microorganism cultures (e.g.,
Pseudomonas aeruginosa, Bacillus licheniformis, Pseudomonas
fluorescens, Bacillus subtilis, etc.). The organic load of this
treatment system is incorporated in part as biomass by the
microbial populations, and almost all the remainder is liberated as
gas (carbonated dioxide, plus methane if ODE membrane aeration
apparatus 701 is used to the influent wastewater feed). Unless the
cell mass formed during the biological treatment is removed from
the wastewater (e.g., by sedimentation, for instance, described
herein), the treatment is largely incomplete because the biomass
itself will appear as organic load in the effluent and the only
pollution reduction accomplished is that fraction liberated as
gas.
[0326] Heretofore utilized rotating biological contactors have
employed a biological film supported on a rotating plastic material
disk or disks in a horizontal plane in a trough through which
settled sewage flows. The disks are only partially submerged and,
therefore, the biomass is subject to periodical removal from the
wastewater flow (the oxygen required to permit respiration is
extracted from atmospheric air). Excess biomass is continually
sloughed from the support disks and treated effluent must therefore
be discharged into a secondary clarifier to settle entrained solids
prior to further treatment.
New Rotating Biological Contactor
[0327] Apparatus 5401 of this aspect of the invention utilizes
immersed conveyor 5403 holding a coil 5404 of woven plastic fabric
conveyor belt material 5601/5603/5605 in a long sheet (e.g., 1,500
m.times.1 m, the various embodiments of which are shown in FIGS.
56. The conveyor could be coated with ZEORAP using a fluidized bed
process (for example, silicon fog) prior to seeding with microbial
cultures. This provides faster and stronger adherence of the
seedling to the rough ZEORAP surface structure. The ZEORAP becomes
a catalyst for the conversion of organic and inorganic
contaminants. The coil is spirally wound (Archimedes' spiral)
around drum 5405 to which the inner coil end is fastened, the other
coil end fastened to take-up drum 5407. The drums are mounted side
by side in tank 5408 allowing alternating coiling and uncoiling of
the belt material from one drum to the other (utilizing
bi-directional motor 5409 connected by belt or chain drive 5411
with each of the drums, motor 5409 connected with a sensor switch
or the like for reversing direction of rotation (not shown)). The
bio media rotates alternatingly perpendicular to the flow of the
contaminated feed water. Drums 5405 and 5407 are carried on driven
shafts 5413 and 5415, and compacted sludge draw-off at the bottom
of tank cones 5417 and 5419 is conducted by screw
conveyor/progressive cavity pump systems 5421 and 5423. Removal of
immobilized microorganisms to control activated sludge thickness of
the conveyor belt occurs at mechanism 5425, and initial seeding or
reseeding of microorganisms on belt material 5601/5603/5605 is via
insert 5427
[0328] The inclined, unsupported free span of conveyor belt
material between the two drums provides a place for continually
sloughing off the excess biomass from the bio-sludge carrying
conveyor belt material. This arrangement provides about a 40%
larger active contact surface area over prior art devices, thus
allowing a smaller footprint with equal or improved performance.
Less energy is required by apparatus 5401 due to a lesser rotating
mass. Manufacturing costs are, likewise, reduced. Because of the
larger active surface area, shorter treatment contact and retention
times are required. The apparatus is easy to maintain and clean
[0329] Belt material 5601/5603/5605 is preferably treated with
genetically altered aerobe microorganisms, and is normally made of
a plastic fabric material 5607/5609/5611 (from VERSEIDAG, for
example, see FIGS. 56a through 56c). Often the fabric material is
supported by a welded on rod support structure 5613 as shown in
FIG. 56a, while still providing gaps for proper aeration to occur.
The biological growth that becomes attached to conveyor belt
material 5601/5603/5605 assimilates the organic materials in the
wastewater. Aeration is provided by the alternating rotation of
conveyor coil 5404, which exposes about 60% of the total conveyor
area to the air after wastewater contact.
[0330] The extent of wastewater treatment is related to the amount
of conveyor belt surface area and the quality and volume of the
influent wastewater. Conveyor speed is a function of the
continuously changing coil(s) diameter. To maintain a constant
conveyor 5403 speed, the rotational speed of both drums 5405 and
5407 is controlled. Automatic drum speed control may be provided,
for example, by means of a digital speed regulator consisting of a
pulse generator (a driver sprocket or the like) that produces
pulses in proportion to motor 5409 speed. An oscillator is used as
a reference. Pulse generator and oscillator counts are compared and
a corresponding error signal is fed to an analog regulator. Since
both drums alternatingly coil on or off and, therefore, rotate at
different speeds, both drums are equipped with clutches
(ratchet-type, overrunning clutches for example). The clutches
alternatingly overrun while coiling off, thus allowing drums to
turn at different speeds.
[0331] Motor 5409 is incorporated in an assembly including a closed
coupled gear reduction unit, and is preferably a reduced voltage
starting, solid state technology to protect the driven load from
mechanical shock. The alternating reversal of motor 5409 is
accomplished by a PLC controlled solid state relay or other means.
Influent feed flow is received at inlet 5429 (also where ODE
technology aerated water stream of previously clarified effluent is
introduced in a closed loop mode to facilitate iron and manganese
precipitation, CH4 gas liberation and further expediting the
sedimentation process within apparatus 5401). Effluent is drawn off
at outlet 5431 for further treatment.
[0332] As may be appreciated from the foregoing apparatus and
methods are provided for water treatment diagnostics, site specific
treatment and plant modeling. A station employing the apparatus and
methods of this invention is mobile, adaptable, and capable of
applying a variety of treatment options and models for purposes of
development of a site-specific full scale treatment proposal.
* * * * *