U.S. patent application number 10/888936 was filed with the patent office on 2006-01-12 for fluid lifting system.
Invention is credited to Milan Rajic.
Application Number | 20060008371 10/888936 |
Document ID | / |
Family ID | 35541565 |
Filed Date | 2006-01-12 |
United States Patent
Application |
20060008371 |
Kind Code |
A1 |
Rajic; Milan |
January 12, 2006 |
Fluid lifting system
Abstract
A fluid lifting for a lifting a geological fluid from a
formation via a well while limiting environmental impact is
provided. The fluid lifting system includes an assembly that is
adapted to be raised and lowered within a lift tube by a cable or
wire-line. When lowered the assembly traps a predetermined volume
of fluid which is then lifted through the lift tube upon raising
the assembly. The assembly includes two main components a valve
body and a collar which is slidable along the valve body. The valve
body includes an axial bore allowing atmospheric air to readily
pass through the valve body so as to equalize air pressure across
the valve body. The collar includes a fluid passage that is open to
fluid flow when the collar is in a raised position along the valve
body and which is closed to fluid flow when in a lowered position
along the valve body.
Inventors: |
Rajic; Milan; (Calgary,
CA) |
Correspondence
Address: |
STEPHEN J. LEWELLYN
933 OLEANDER WAY SOUTH
SUITE 3
SOUTH PASADENA
FL
33707
US
|
Family ID: |
35541565 |
Appl. No.: |
10/888936 |
Filed: |
July 12, 2004 |
Current U.S.
Class: |
417/548 ;
137/554; 417/555.1 |
Current CPC
Class: |
F04B 53/12 20130101;
F04B 47/02 20130101; Y10T 137/8242 20150401; F04B 47/026
20130101 |
Class at
Publication: |
417/548 ;
137/554; 417/555.1 |
International
Class: |
F04B 53/00 20060101
F04B053/00; F04B 53/12 20060101 F04B053/12 |
Claims
1. A fluid lifting system comprising: a valve body adapted to be
raised and lowered within a lift tube, said valve body defining an
axial bore, said axial bore allowing fluid to freely flow through
said valve body; a collar slidably received by said valve body,
said collar defining at least one fluid passage passing
therethrough, wherein said fluid passage is open allowing fluid
flow therethrough when said collar is in a raised position on said
valve body and said fluid passage is closed preventing fluid flow
therethrough when said collar is in a lowered position on said
valve body; and a lift cable attached to said valve body.
2. The fluid lifting system of claim 1, further comprising: a
conduit attached to and extending upwardly from said valve body and
in fluid communication with said axial bore defined by said valve
body.
3. The fluid lifting system of claim 1, wherein said lift tube
defines a sand screen.
4. The fluid lifting system of claim 1, wherein said collar
contacts said lift tube and creates a fluid tight seal
therewith.
5. A ground water lifting system comprising: a valve body slidably
positioned within a lift tube, said valve body defining an axial
bore, said axial bore allowing the equalization of fluid pressure
across said valve body; a collar mounted to said valve body so as
to allow said collar to reciprocate a predetermined stroke along a
section of said valve body, said collar defining at least one fluid
passage extending therethrough, wherein said fluid passage is
closed to fluid flow when said collar is at its lowest most point
in said stroke, said collar defining a fluid tight seal with said
lift tube; and a lift cable, said lift attached to said valve body
for raising and lowering said valve body within said lift tube.
6. The ground water lifting system of claim 5, wherein said valve
body defines a lower stop and an upper stop at a spaced distance
from said lower stop, said upper stop defining an upper limit of
said stroke and said lower stop defining a lower limit of said
stroke.
7. The ground water lifting system of claim 6, wherein said lower
stop is a shoulder which engages said collar when said collar is at
said lower limit and which seals said at least one fluid passage
defined by said collar.
8. The ground water lifting system of claim 7, wherein said
shoulder is a tapered shoulder.
9. The ground water lifting system of claim 5, further comprising a
conduit attached to and extending upwardly from said valve body and
in fluid communication with said axially bore thereof.
10. The ground water lifting system of claim 5, wherein said lift
tube defines a sand screen along a section of said lift tube.
11. The ground water lifting system of claim 5, wherein said collar
sinks at a slower rate then said valve body when said valve body
and said collar are lowered into a column of fluid contained within
said lift tube.
Description
BACKGROUND OF THE INVENTION
[0001] Field of the Invention
[0002] The present invention relates generally to a fluid lift
system. More particularly, relating to fluid lift system for
lifting a geological fluid, such as water from a formation with
reduced environmental impact and sample contamination.
[0003] It is desirable to lift a high volume of fluid, such as
water from a well for the purpose of sampling and testing the
sample for ecological requirements. To get a representative sample
for testing, it is necessary to retrieve a volume of water that is
equal to three times the volume of water present above the well
screen. The sample volume varies from well to well and typically
falls within the range of 50 to 1000 liters.
[0004] It is critical when lifting the fluid sample from the well
not to apply pressure, vacuum, chemicals, aerate or vibrations to
the water level of the fluid to prevent changing or damaging the
geological formation from which the sample is drawn. Damaging or
changing the formation can contaminate the fluid being lifted which
can result in false test results during the testing of the
sample.
[0005] Current fluid lifting systems include submersible pumps,
inertial pumps such as the ones available under the name WaTerra
Pump, and hand pumps. Submersible pumps are limited by the depth of
a well and the retrieval rate or lift rate rapidly drops off with
the depth of the pump, they are sensitive to sand and hydrocarbon
contents, and tend to be non-durable. WaTerra pumps tend to have a
problem with lift tube bending, create vibrations and have a low
retrieval rate. Hand pumps while do not have a depth limit they are
difficult to operate, have a very low retrieval rate and include
the danger of being dropped into the well.
[0006] In addition, current water sampling standards are becoming
much more labor intensive requiring more frequent sampling and
sampling from deeper wells. Therefore, a need exists for a new and
improved fluid lifting system that has a higher rater of retrieval,
includes no driven mechanical elements, is easy to operate, does
not impact the formation and which is not well depth limited. In
this regard, the present invention substantially fulfills this
need.
SUMMARY OF THE INVENTION
[0007] In accordance with the present invention, an apparatus for a
lifting a geological fluid from a formation via a well while
limiting environmental impact is provided.
[0008] The apparatus essentially comprises an assembly that is
adapted to be raised and lowered within a lift tube by a cable or
wire-line. When lowered the assembly traps a predetermined volume
of fluid which is then lifted through the lift tube upon raising
the assembly. The assembly includes two main components a valve
body and a collar which is slidable along the valve body. The valve
body includes an axial bore allowing atmospheric air to readily
pass through the valve body so as to equalize air pressure across
the valve body. The collar includes a fluid passage that is open to
fluid flow when the collar is in a raised position along the valve
body and which is closed to fluid flow when in a lowered position
along the valve body. In addition, the collar makes a fluid tight
engagement with the lift tube.
[0009] In operation, the assembly is lowered down the lift tube and
into a column of fluid, such as water present above the well
screen. Upon lowering the assembly into the column of water, the
collar is raised along the valve body thereby allowing a volume of
water to readily pass through the collar and collect within a trap
zone. Once the assembly has been lowered to a desired depth, the
collar slides down along the valve body by under the force of
gravity to a point where the fluid passage is closed. The assembly
is then raised lifting the volume of water contained within the
trap zone. Upon lifting, air is readily passed through the axial
bore of the valve body equalizing pressure across the valve body to
eliminate creating a vacuum between the assembly and the column of
water remaining in the lift tube. The column of water contained in
the trap zone applies a downward pressure on the collar thereby
increasing the seal of the fluid passage preventing water from
draining back through the fluid passage and into the remaining
water in the formation. The assembly is raised to height where the
water contained within the trap zone is drawn off into a collection
container and then is lowered down the lift tube to collect an
additional volume of water from the formation. This process is
repeated until the desired quantity of water is retrieved from the
well.
[0010] There has thus been outlined, rather broadly, the more
important features of the invention in order that the detailed
description thereof that follows may be better understood and in
order that the present contribution to the art may be better
appreciated.
[0011] Numerous objects, features and advantages of the present
invention will be readily apparent to those of ordinary skill in
the art upon a reading of the following detailed description of
presently preferred, but nonetheless illustrative, embodiments of
the present invention when taken in conjunction with the
accompanying drawings. The invention is capable of other
embodiments and of being practiced and carried out in various ways.
Also, it is to be understood that the phraseology and terminology
employed herein are for the purpose of descriptions and should not
be regarded as limiting.
[0012] As such, those skilled in the art will appreciate that the
conception, upon which this disclosure is based, may readily be
utilized as a basis for the designing of other structures, methods
and systems for carrying out the several purposes of the present
invention. It is important, therefore, that the claims be regarded
as including such equivalent constructions insofar as they do not
depart from the spirit and scope of the present invention.
[0013] For a better understanding of the invention, its operating
advantages and the specific objects attained by its uses, reference
should be had to the accompanying drawings and descriptive matter
in which there is illustrated preferred embodiments of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will be better understood and objects other
than those set forth above will become apparent when consideration
is given to the following detailed description thereof. Such
description makes reference to the annexed drawings wherein:
[0015] FIG. 1 is a side elevation view of a preferred embodiment of
the fluid lifting system constructed in accordance with the
principles of the present invention in use.
[0016] FIG. 2 illustrates the fluid lifting system in a partially
lowered position.
[0017] FIG. 3 illustrates the fluid lifting system in a fully
lowered position.
[0018] FIG. 4 illustrates the fluid lifting system in a partially
raised position subsequent to the fully lowered position
illustrated in FIG. 3.
[0019] FIG. 5 illustrates the fluid lifting in an intermediate
raised position subsequent to the position illustrated in FIG.
4.
[0020] FIG. 6 illustrates the fluid lifting system in a fully
raised position.
[0021] The same reference numerals refer to the same parts
throughout the various figures.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Referring now to the drawings, and particularly to FIGS.
1-6, a preferred embodiment of the fluid lift system of the present
invention is shown and generally designated by the reference
numeral 10.
[0023] In FIG. 1, a new and improved fluid lift system 10 of the
present invention for lifting a fluid, such as water from a
geological formation is illustrated and will be described. More
particularly, the fluid lift system 10 includes a lift assembly 12
that is adapted to be raised and lowered within a lift tube 14 by a
cable or wire-line 16.
[0024] The lift assembly 12 includes a valve body 18 having a first
end 20 and a second end 22 and a collar 24 slidable along a section
of the valve body intermediate ends 20 and 22. The valve body 18
further defines an axial bore 26 extending therethrough from the
first end 20 to the second end 22. Fluid, air or liquid is free to
flow either in an upwardly or downwardly direction through the
axial bore 26 for the purpose of equalizing pressure across the
valve body 18. The collar 24 includes a fluid passage 28 which is
open to readily pass fluid therethrough when the collar is in a
raised position on the valve body 18 and which is sealed when the
collar is in a lowered position on the valve body.
[0025] The collar 24 is restrained to slide along the valve body 18
a predetermined stroke which has an upper limit and a lower limit.
The upper and lower limits are defined by an upper stop 30 and a
lower stop 32. Preferably, the upper stop 30 is a radial flange
extending from the surface of the valve body 18 and the lower stop
32 is shoulder extending from the valve body. Most preferably, the
shouldered 32 is a tapered shoulder. Even more preferably, the
taper is in a downward direction. When the collar 24 is in the
lower limit position along the valve body 18, the fluid passage 28
is sealed preventing fluid flow therethrough by the shoulder 32. As
the collar 24 is raised from the shoulder 32, the fluid passage 28
is opened to fluid flow.
[0026] While the collar 24 is free to reciprocate a predetermined
stroke along the valve body 18, the perimeter of the collar is
engaged with the lift tube 16 making a fluid seal therewith. The
fluid seal between the collar 24 and the lift tube 16 ensures all
fluid passing by the collar must pass through the fluid passage 28,
which is controlled based upon the position of the collar along the
valve body 18.
[0027] The first end 20 of the valve body, an upper surface 34 of
the collar 24 and the annulus of the lift tube above the shoulder
32 defines a trap zone 36. Preferably, a conduit 38 is attached to
the first end 20 of the valve body extending the height trap zone
36 above the shoulder 32. The conduit 38 can be sized to tailor the
volume of the trap zone 36 for a particular application. The
conduit 38 is attached to the first end 20 of the valve body 18 so
that the conduit and the axial bore 26 of the valve body are in
fluid communication so that air or fluid passing therethrough can
also freely enter the conduit.
[0028] Referring now to FIG. 2, the lift assembly 12 is illustrated
in an intermediate lowered position in the lift tube 14, where the
lift assembly is partially lowered into a column of formation water
40 contained within the lift tube. In this intermediate position,
the collar 24 is in a raised position allowing a quantity of water
from the water column 40 to pass through the fluid passage 28 and
into the trap zone 36, and a quantity of water from the water
column enters the axial bore 26 and conduit 38 to equalize pressure
across the valve body to prevent compressive forces from being
applied to the water column. Collar 24 is designed to have a slower
sinking rate then that of the valve body 18 so as to raise the
collar 24 along the valve body during the initial lowering of the
lift assembly 12 into the water column 40.
[0029] Turning now to FIG. 3, the lift assembly 12 is completed
lowered to a desired depth down the lift tube 14 and into the water
column 40. Preferably, the lift assembly 12 is lowered to a depth
so that the upper surface 34 of the collar is at the same depth as
the top of the well screen 42. At this point, the collar 24 has
been allowed to sink until its lowest most point where the fluid
passage 28 is sealed. Preferably, the passage 28 is sealed by
engagement of the collar 18 with the shoulder 32. In addition at
this point, the maximum volume of water entering the trap zone 36
from the water column 40 is contained within the trap zone and
pressure across the valve body 18 is equalized.
[0030] Referring now to FIG. 4, the lift assembly 12 is illustrated
partially raised from the water column 40. During this period,
first a hydrostatic pressure created by the volume of water
contained within the trap zone 36 is applied to the upper surface
34 of the collar 24 increasing the sealing of the fluid passage 28
by increasing the contact pressure between the shoulder 32 and the
collar. Second, atmospheric air present within the lift tube 14 is
pulled through the conduit 38 into the axial bore 26 of the valve
body 18 by a differential pressure present within the axial bore
created by water within the water column 40 flowing downwardly
through the axial bore. As atmospheric air continues to enter the
axial bore 26 a vacuum is prevented from occurring between the lift
assembly 12 and the water column 40. The flow of air is indicated
by the open arrows and the flow of water is indicated by the filled
arrows. This equalization of pressure across the valve body 18
during raising thereof is critical to the operation of the fluid
lift system 10.
[0031] FIG. 5 illustrates the lift assembly 12 completely raised
from the water column 40, where atmospheric air continues to travel
through the valve body 18 to ensure a vacuum is not created between
the lift assembly and the water column 40. As the lift assembly 12
is continually raised in the lift tube 14 the water contained
within the trap zone 36 is drawn off and out of the lift tube, as
illustrated in FIG. 6.
[0032] Once the water is completely drawn off from the trap zone
36, the lift assembly 12 is lowered back down the lift tube 14
where the complete lift cycle begins once again. This process can
be repeated a number of times until a desired volume of water is
retrieved from the well. Preferably, the volume retrieved from the
well is equal to three times the volume of water in the water
column 40 present above the well screen 42.
[0033] A number of embodiments of the present invention have been
described. Nevertheless, it will be understood that various
modifications may be made without departing from the spirit and
scope of the invention. Accordingly, other embodiments are within
the scope of the following claims.
* * * * *