U.S. patent application number 12/764606 was filed with the patent office on 2010-10-21 for catalytic water treatment method and apparatus.
This patent application is currently assigned to ECOLAB USA INC.. Invention is credited to Lee J. Monsrud, Keith E. Olson, Douglas J. Prideaux, Paul F. Schacht, Eric V. Schmidt, Kim R. Smith.
Application Number | 20100263688 12/764606 |
Document ID | / |
Family ID | 42980058 |
Filed Date | 2010-10-21 |
United States Patent
Application |
20100263688 |
Kind Code |
A1 |
Monsrud; Lee J. ; et
al. |
October 21, 2010 |
CATALYTIC WATER TREATMENT METHOD AND APPARATUS
Abstract
The present invention relates to methods, apparatuses, and
systems for treating water. The methods, apparatuses and systems
reduce solubilized water hardness using various water treatment
agents bound to a supporting material. The present invention also
includes methods of employing treated water, for example, in
cleaning or food processing applications.
Inventors: |
Monsrud; Lee J.; (Inver
Grove Heights, MN) ; Prideaux; Douglas J.; (Eden
Prarie, MN) ; Olson; Keith E.; (Apple Valley, MN)
; Smith; Kim R.; (Woodbury, MN) ; Schacht; Paul
F.; (Oakdale, MN) ; Schmidt; Eric V.;
(Woodbury, MN) |
Correspondence
Address: |
ECOLAB USA INC.
MAIL STOP ESC-F7, 655 LONE OAK DRIVE
EAGAN
MN
55121
US
|
Assignee: |
ECOLAB USA INC.
St. Paul
MN
|
Family ID: |
42980058 |
Appl. No.: |
12/764606 |
Filed: |
April 21, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61171145 |
Apr 21, 2009 |
|
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|
61261610 |
Nov 16, 2009 |
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Current U.S.
Class: |
134/18 ; 210/205;
210/679 |
Current CPC
Class: |
C02F 1/5236 20130101;
C02F 2303/22 20130101; C02F 1/42 20130101; C02F 2201/006 20130101;
C02F 1/725 20130101; C02F 5/10 20130101; C02F 2001/425 20130101;
E03B 7/074 20130101; C02F 5/02 20130101 |
Class at
Publication: |
134/18 ; 210/205;
210/679 |
International
Class: |
C02F 1/42 20060101
C02F001/42; B08B 7/04 20060101 B08B007/04 |
Claims
1. An apparatus for treating a water source comprising: an inlet
for providing the water source to a treatment reservoir; one or
more catalysts positioned inside the treatment reservoir, the
catalyst comprising a water treatment agent bound to a supporting
material, wherein the water treatment agent is selected from the
group consisting of a source of magnesium ions, aluminum ions, zinc
ions, titanium ions and mixtures thereof; and an outlet for
providing treated water from the reservoir.
2. The apparatus of claim 1, wherein the supporting material
comprises an ionic resin.
3. The apparatus of claim 2, wherein the resin comprises a weak
acid cation resin.
4. The apparatus of claim 1, wherein the water treatment agent
comprises magnesium.
5. The apparatus of claim 1, wherein the supporting material
comprises beads of resin.
6. The apparatus of claim 1, wherein the catalyst is agitated.
7. The apparatus of claim 1, wherein the treatment reservoir
comprises a removable cartridge.
8. The apparatus of claim 1, wherein the supporting material is
selected from the group consisting of an acrylic acid polymer, a
methacrylic acid polymer, and combinations thereof.
9. The apparatus of claim 1, wherein the supporting material
comprises a carboxylic acid polymer.
10. The apparatus of claim 1, wherein the water treatment agent is
ionically bound to the supporting material.
11. The apparatus of claim 1, wherein the supporting material is a
resin that binds magnesium ions preferentially over calcium
ions.
12. The apparatus of claim 1, wherein the treatment reservoir
further comprises one or more metal oxides or hydroxides.
13. The apparatus of claim 12, wherein the metal oxide is selected
from magnesium oxides, aluminum oxides, titanium oxides or mixtures
thereof.
14. The apparatus of claim 1, wherein the apparatus is located in a
washing system.
15. The apparatus of claim 14, wherein the washing system is an
automated washing system.
16. The apparatus of claim 14, wherein the automated washing system
is selected from the group consisting of an automatic ware washing
machine, automatic vehicle washing system, an instrument washer,
clean in place system, food processing cleaning system, bottle
washer, an automatic laundry washing machine, and combinations
thereof.
17. The apparatus of claim 1, wherein the apparatus is located
upstream on a water line feeding a washing machine.
18. The apparatus of claim 17, wherein the washing machine is an
automatic washing machine selected from the group consisting of an
automatic ware washing machine, automatic vehicle washing system,
instrument washer, clean in place system, food processing cleaning
system, bottle washer, an automatic laundry washing machine, and
combinations thereof.
19. The apparatus of claim 1, wherein the treated water from the
outlet does not need to be filtered prior to use.
20. A method of treating a water source comprising: contacting the
water source with a catalyst, the catalyst comprising a water
treatment agent bound to a supporting material, wherein the water
treatment agent is selected from the group consisting of a source
of magnesium ions, aluminum ions, zinc ions, titanium ions and
mixtures thereof, such that the water is treated.
21. The method of claim 20, wherein the treated water has a
substantially reduced solubilized water hardness.
22. The method of claim 20, wherein the step of contacting
comprises passing the water source through the catalyst.
23. The method of claim 20, further comprising agitating the
catalyst.
24. The method of claim 20, wherein the supporting material is an
ionic resin.
25. The method of claim 24, wherein the supporting material is a
weak acid cation resin.
26. The method of claim 20, wherein the water treatment agent
comprises magnesium.
27. The method of claim 20, wherein the supporting material
comprises beads of resin.
28. The method of claim 20, wherein the supporting material is
selected from the group consisting of an acrylic acid polymer, a
methacrylic acid polymer, and combinations thereof.
29. The method of claim 20, wherein the catalyst is contained in a
treatment reservoir.
30. The method of claim 29, wherein the treatment reservoir
comprises a removable cartridge.
31. The method of claim 20, wherein the water to be treated is at a
temperature of between about 10.degree. C. and about 90.degree.
C.
32. The method of claim 20, wherein the water to be treated has a
pH of between about 6 and about 8.
33. The method of claim 20, wherein the water to be treated has a
pH of greater than 8.
34. The method of claim 20, wherein the treated water does not need
to be filtered after treatment.
35. The method of claim 20, wherein the treated water does not have
a substantially reduced water hardness level after treatment.
36. The method of claim 20, wherein the pH of the treated water is
substantially similar to the pH of the water source prior to
treatment.
37. The method of claim 20, wherein the catalyst further comprises
one or more oxides or hydroxides of magnesium, aluminum or titanium
not bound to the supporting material.
38. The method of claim 20, wherein the water contacted with the
catalyst forms a precipitate comprising a cation different than the
water treatment agent.
39. A method of using a treated water source to clean an article,
the method comprising: treating a water source with a catalyst, the
catalyst comprising a water treatment agent bound to a supporting
material, wherein the water treatment agent is selected from the
group consisting of a source of magnesium ions, aluminum ions, zinc
ions, titanium ions and mixtures thereof; forming a use solution
with the treated water and a detergent; and contacting the article
with the use solution such that the article is cleaned.
40. The method of claim 39, wherein the catalyst further comprises
one or more oxides or hydroxides of magnesium, aluminum or
titanium.
41. The method of claim 39, wherein the detergent is substantially
free of a chelant, builder, threshold agent, sequestrant or
combinations thereof.
42. The method of claim 39, wherein the step of contacting the
article with the use solution is performed in an automatic washing
machine selected from the group consisting of an automatic ware
washing machine, automatic dishwashing vehicle washing system,
instrument washer, clean in place system, food processing cleaning
system, bottle washer, and an automatic laundry washing
machine.
43. A method for treating a food processing stream comprising:
contacting the food processing stream with a catalyst, the catalyst
comprising a water treatment agent bound to a supporting material,
wherein the water treatment agent comprises a source of magnesium
ions, such that the food processing stream is treated.
44. The method of claim 43, wherein the supporting material
comprises a resin.
45. The method of claim 44, wherein the resin comprises a weak acid
cation resin.
46. The method of claim 43, wherein the step of contacting
comprises passing the food processing stream through the
catalyst.
47. The method of claim 43, wherein the food processing stream
comprises a whey permeate.
48. The method of claim 43, further comprising concentrating the
treated food processing stream.
49. The method of claim 48, wherein the step of concentrating the
food processing stream is selected from the group consisting of
passing the treated food processing stream through a reverse
osmosis system, passing the treated food processing stream through
a nanofiltration system, passing the treated food processing stream
through an ultrafiltration system, passing the treated food
processing stream through an evaporator, and combinations thereof.
Description
RELATED APPLICATIONS
[0001] This application claims priority to and is related to U.S.
Provisional Application Ser. No. 61/171,145 filed on Apr. 21, 2009
and entitled "Catalytic Water Treatment Method and Apparatus." The
entire contents of this patent application are hereby expressly
incorporated herein by reference including, without limitation, the
specification, claims, and abstract, as well as any figures,
tables, or drawings thereof.
[0002] This application also claims priority and is related to U.S.
Provisional Application Ser. No. 61/261,610 filed on Nov. 16, 2009
and entitled "Methods and Apparatus for Controlling Water
Hardness." The entire contents of this patent application are
hereby expressly incorporated herein by reference including,
without limitation, the specification, claims, and abstract, as
well as any figures, tables, or drawings thereof.
[0003] This application is also related to U.S. application Ser.
No. ______ (Attorney Docket No. 2699USU1) filed concurrently
herewith and entitled "Methods and Apparatus for Controlling Water
Hardness." The entire contents of this patent application are
hereby expressly incorporated herein by reference including,
without limitation, the specification, claims, and abstract, as
well as any figures, tables, or drawings thereof.
FIELD
[0004] The present invention relates to methods and devices for
treating an aqueous system, i.e., a water source or stream. In
particular, the present invention provides methods and devices for
reducing solubilized water hardness using various water treatment
agents bound to a supporting material. Methods for inhibiting or
reducing scale formation are also provided. The present invention
also relates to methods of employing treated water, for example, in
cleaning processes.
BACKGROUND
[0005] The level of hardness in water can have a deleterious effect
in many systems. For example, when hard water alone, or in
conjunction with cleaning compositions, contacts a surface, it can
cause precipitation of hard water scale on the contacted surface.
In general, hard water refers to water having a total level of
calcium and magnesium ions in excess of about 100 ppm expressed in
units of ppm calcium carbonate. Often, the molar ratio of calcium
to magnesium in hard water is about 2:1 or about 3:2. Although most
locations have hard water, water hardness tends to vary from one
location to another.
[0006] Water hardness has been addressed in a number of ways. One
method currently used to soften water is via ion exchange, e.g., by
exchanging the calcium and magnesium ions in the water with sodium
associated with a resin bed in a water softening unit. The calcium
and magnesium adhere to a resin in the softener. When the resin
becomes saturated it is necessary to regenerate it using large
amounts of sodium chloride dissolved in water. The sodium displaces
the calcium and magnesium, which is flushed out in a briny solution
along with the chloride from the added sodium chloride. When water
softeners regenerate they produce a waste stream that contains
significant amounts of chloride, and salts including sodium,
calcium and magnesium salts, creating a burden on the system, e.g.,
sewer system, in which they are disposed of, including a multitude
of downstream water re-use applications like potable water usages
and agriculture. Further, traditional water softeners add to the
salt content in discharge surface waters, which has become an
environmental issue in certain locations. Therefore a method to
handle water hardness without the use of large amounts of sodium
chloride is needed.
[0007] Hard water is also known to reduce the efficacy of
detergents, for example, by forming films on surfaces, and reacting
with detergent components making the detergent less functional in
the cleaning process. One method for counteracting this includes
adding chelating agents or sequestrants into detersive compositions
that are intended to be mixed with hard water in an amount
sufficient to handle the hardness. In several instances, chelators
and sequestrants (e.g., phosphates and NTA) have been found to
cause environmental or health issues. However, in many instances
the water hardness exceeds the chelating capacity of the
composition. As a result, free calcium ions may be available to
attack active components of the composition, to cause corrosion or
precipitation, or to cause other deleterious effects, such as poor
cleaning effectiveness or lime scale build up.
SUMMARY
[0008] In some aspects, the present invention provides an apparatus
for treating water. The apparatus includes: an inlet for providing
the water source to a treatment reservoir. One or more catalysts
are positioned inside the treatment reservoir. The catalysts
comprise a water treatment agent bound to a supporting material.
The water treatment agent is selected from the group consisting of
a source of magnesium ions, aluminum ions, zinc ions, titanium ions
and mixtures thereof. The apparatus also includes an outlet for
providing treated water from the reservoir.
[0009] In some embodiments, the apparatus is located in a washing
system. For example, in some embodiments, the apparatus is located
in an automatic washing system selected from the group consisting
of an automatic ware washing or dish washing machine, automatic
vehicle washing system, an instrument washer, clean in place
system, food processing cleaning system, bottle washer, an
automatic laundry washing machine, and combinations thereof. The
apparatus can be located upstream from the water line feeding a
washing machine in some embodiments.
[0010] In other aspects, the present invention relates to a method
of treating a water source. The method includes contacting the
water source with a catalyst. The catalyst comprises a water
treatment agent bound to a supporting material, wherein the water
treatment agent is selected from the group consisting of a source
of magnesium ions, aluminum ions, zinc ions, titanium ions and
mixtures thereof, such that the water is treated. In some
embodiments, the treated water has a substantially reduced
solubilized water hardness. In some embodiments, the step of
contacting can include passing the water source through the
catalyst.
[0011] In other aspects, the present invention relates to methods
of using a treated water source to clean an article. The method
comprises treating a water source with a catalyst. The catalyst
comprises a water treatment agent bound to a supporting material,
wherein the water treatment agent is selected from the group
consisting of a source of magnesium ions, aluminum ions, zinc ions,
titanium ions and mixtures thereof. A use solution is formed with
the treated water and a detergent; and contacting the article with
the use solution such that the article is cleaned.
[0012] In still yet other aspects, the present invention relates to
methods for treating a food processing stream. The method comprises
contacting the food processing stream with a catalyst. The catalyst
comprises a water treatment agent bound to a supporting material,
wherein the water treatment agent comprises a source of magnesium
ions, such that the food processing stream is treated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic view of an apparatus for use in
treating water according to embodiments of the invention.
[0014] FIG. 2 is a photograph of test glasses washed in water which
was treated to reduce solubilized water harness according to
embodiments of the invention.
[0015] FIG. 3A is a photograph of test glasses washed in detergent
without builders and rinse aids with untreated water.
[0016] FIG. 3B is a photograph of test glasses washed in detergent
with out builders and rinse aids and with water treated to reduce
solubilized water hardness according to embodiments of the
invention.
[0017] FIG. 3C is a photograph of test glasses washed in detergent
with builders and rinse aids and with untreated water.
[0018] FIG. 3D is a photograph of test glasses washed in detergent
with builders and rinse aids and with water treated to reduce
solubilized water hardness according to embodiments of the
invention.
[0019] FIGS. 4A and 4B are photographs of test glasses washed with
untreated water, water treated with a calcium bound resin, water
treated with a magnesium bound resin, and water treated with a
hydrogen bound resin.
DESCRIPTION
[0020] The present invention relates to apparatuses and methods for
treating water, such that the solubilized water hardness is
controlled and/or reduced. In some embodiments, the solubilized
calcium portion of water hardness is reduced. In some aspects, a
water treatment agent is bound to a resin and is used to treat the
water. In some embodiments, the water treatment agent is magnesium
and the resin is a weak acid cation resin.
[0021] The water treated in accordance with the methods of the
present invention has many beneficial effects, including, but not
limited to, reduction of scale and soiling in areas where hard
water can cause soiling, protecting equipment, e.g., industrial
equipment, from scale build up, increased cleaning efficacy when
used with conventional detersive compositions, and reducing the
need for specific chemistries, e.g., those containing threshold
agents, chelating agents, or sequestrants, or phosphorous, in
downstream cleaning processes.
[0022] In some aspects, the present invention provides methods for
treating water. In some embodiments, the solubilized calcium
portion of water hardness is reduced. In some embodiments, the
water is contacted with a catalyst including a water treatment
agent. In other aspects, the present invention provides methods for
inhibiting or reducing scale formation in an aqueous system
including contacting the aqueous system with a catalyst including
one or more water treatment agents bound to a support material
and/or one or more unbound conversion agents.
[0023] So that the invention may be more readily understood certain
terms are first defined.
[0024] As used herein, the terms "builder," "chelating agent," and
"sequestrant" refer to a compound that forms a complex (soluble or
not) with water hardness ions (from the wash water, soil and
substrates being washed) in a specific molar ratio. Chelating
agents that can form a water soluble complex include sodium
tripolyphosphate, EDTA, DTPA, NTA, citrate, and the like.
Sequestrants that can form an insoluble complex include sodium
triphosphate, zeolite A, and the like. As used herein, the terms
"builder," "chelating agent," and "sequestrant" are synonymous.
[0025] As used herein, the term "free of chelating agent" or
"substantially free of chelating agent" refers to a composition,
mixture, or ingredients that does not contain a chelating agent,
builder, or sequestrant or to which only a limited amount of a
chelating agent, builder, or sequestrant has been added. Should a
chelating agent, builder, or sequestrant be present, the amount of
a chelating agent, builder, or sequestrant shall be less than about
7 wt %. In some embodiments, such an amount of a chelating agent,
builder, or sequestrant is less than about 2 wt %, less then about
0.5 wt %, or less than about 0.1 wt %.
[0026] As used herein, the term "lacking an effective amount of
chelating agent" refers to a composition, mixture, or ingredients
that contains too little chelating agent, builder, or sequestrant
to measurably affect the hardness of water.
[0027] As used herein, the term "solubilized water hardness" refers
to hardness minerals dissolved in ionic form in an aqueous system
or source, i.e., Ca.sup.++ and Mg.sup.++. Solubilized water
hardness does not refer to hardness ions when they are in a
precipitated state, i.e., when the solubility limit of the various
compounds of calcium and magnesium in water is exceeded and those
compounds precipitate as various salts such as, for example,
calcium carbonate and magnesium carbonate.
[0028] As used herein, the term "water soluble" refers to a
compound that can be dissolved in water at a concentration of more
than 1 wt-%.
[0029] As used herein, the terms "slightly soluble" or "slightly
water soluble" refer to a compound that can be dissolved in water
only to a concentration of 0.1 to 1.0 wt-%.
[0030] As used herein, the term "substantially water insoluble" or
"water insoluble" refers to a compound that can be dissolved in
water only to a concentration of less than 0.1 wt-%. For example,
magnesium oxide is considered to be insoluble as it has a water
solubility (wt %) of about 0.00062 in cold water, and about 0.00860
in hot water. Other insoluble compounds for use with the methods of
the present invention include, for example: magnesium hydroxide
with a water solubility of 0.00090 in cold water and 0.00400 in hot
water; aragonite with a water solubility of 0.00153 in cold water
and 0.00190 in hot water; and calcite with a water solubility of
0.00140 in cold water and 0.00180 in hot water.
[0031] As used herein, the term "threshold agent" refers to a
compound that inhibits crystallization of water hardness ions from
solution, but that need not form a specific complex with the water
hardness ion. This distinguishes a threshold agent from a chelating
agent or sequestrant. Threshold agents include a polyacrylate, a
polymethacrylate, an olefin/maleic copolymer, and the like.
[0032] As used herein, the term "free of threshold agent" or
"substantially free of threshold agent" refers to a composition,
mixture, or ingredient that does not contain a threshold agent or
to which only a limited amount of a threshold agent has been added.
Should a threshold agent be present, the amount of a threshold
agent shall be less than about 7 wt %. In some embodiments, such an
amount of a threshold agent is less than about 2 wt-%. In other
embodiments, such an amount of a threshold agent is less then about
0.5 wt-%. In still yet other embodiments, such an amount of a
threshold agent is less than about 0.1 wt-%.
[0033] As used herein, the term "antiredeposition agent" refers to
a compound that helps keep a soil composition suspended in water
instead of redepositing onto the object being cleaned.
[0034] As used herein, the term "phosphate-free" or "substantially
phosphate-free" refers to a composition, mixture, or ingredient
that does not contain a phosphate or phosphate-containing compound
or to which a phosphate or phosphate-containing compound has not
been added. Should a phosphate or phosphate-containing compound be
present through contamination of a phosphate-free composition,
mixture, or ingredients, the amount of phosphate shall be less than
about 1.0 wt %. In some embodiments, the amount of phosphate is
less than about 0.5 wt %. In other embodiments, the amount of
phosphate is less then about 0.1 wt %. In still yet other
embodiments, the amount of phosphate is less than about 0.01 wt
%.
[0035] As used herein, the term "phosphorus-free" or "substantially
phosphorus-free" refers to a composition, mixture, or ingredient
that does not contain phosphorus or a phosphorus-containing
compound or to which phosphorus or a phosphorus-containing compound
has not been added. Should phosphorus or a phosphorus-containing
compound be present through contamination of a phosphorus-free
composition, mixture, or ingredients, the amount of phosphorus
shall be less than about 1.0 wt %. In some embodiments, the amount
of phosphorous is less than about 0.5 wt %. In other embodiments,
the amount of phosphorus is less than about 0.1 wt %. In still yet
other embodiments, the amount of phosphorus is less than about 0.01
wt %.
[0036] "Cleaning" means to perform or aid in soil removal,
bleaching, microbial population reduction, or combination
thereof.
[0037] As used herein, the term "ware" refers to items such as
eating and cooking utensils and dishes and other hard surfaces such
as showers, sinks, toilets, bathtubs, countertops, windows,
mirrors, transportation vehicles, and floors. As used herein, the
term "warewashing" refers to washing, cleaning, or rinsing
ware.
[0038] As used herein, the term "hard surface" includes showers,
sinks, toilets, bathtubs, countertops, windows, mirrors,
transportation vehicles, floors, and the like.
[0039] As used herein, the phrase "health care surface" refers to a
surface of an instrument, a device, a cart, a cage, furniture, a
structure, a building, or the like that is employed as part of a
health care activity. Examples of health care surfaces include
surfaces of medical or dental instruments, of medical or dental
devices, of autoclaves and sterilizers, of electronic apparatus
employed for monitoring patient health, and of floors, walls, or
fixtures of structures in which health care occurs. Health care
surfaces are found in hospital, surgical, infirmity, birthing,
mortuary, and clinical diagnosis rooms. These surfaces can be those
typified as "hard surfaces" (such as walls, floors, bed-pans,
etc.,), or fabric surfaces, e.g., knit, woven, and non-woven
surfaces (such as surgical garments, draperies, bed linens,
bandages, etc.,), or patient-care equipment (such as respirators,
diagnostic equipment, shunts, body scopes, wheel chairs, beds,
etc.,), or surgical and diagnostic equipment. Health care surfaces
include articles and surfaces employed in animal health care.
[0040] As used herein, the term "instrument" refers to the various
medical or dental instruments or devices that can benefit from
cleaning using water treated according to the methods of the
present invention.
[0041] As used herein, the phrases "medical instrument," "dental
instrument," "medical device," "dental device," "medical
equipment," or "dental equipment" refer to instruments, devices,
tools, appliances, apparatus, and equipment used in medicine or
dentistry. Such instruments, devices, and equipment can be cold
sterilized, soaked or washed and then heat sterilized, or otherwise
benefit from cleaning using water treated according to the present
invention. These various instruments, devices and equipment
include, but are not limited to: diagnostic instruments, trays,
pans, holders, racks, forceps, scissors, shears, saws (e.g. bone
saws and their blades), hemostats, knives, chisels, rongeurs,
files, nippers, drills, drill bits, rasps, burrs, spreaders,
breakers, elevators, clamps, needle holders, carriers, clips,
hooks, gouges, curettes, retractors, straightener, punches,
extractors, scoops, keratomes, spatulas, expressors, trocars,
dilators, cages, glassware, tubing, catheters, cannulas, plugs,
stents, scopes (e.g., endoscopes, stethoscopes, and arthoscopes)
and related equipment, and the like, or combinations thereof.
[0042] As used herein, the term "laundry," refers to woven and
non-woven fabrics, and textiles. For example, laundry can include,
but is not limited to, clothing, bedding, towels and the like.
[0043] As used herein, the term "water source," refers to any
source of water that can be used with the methods, systems and
apparatus of the present invention. Exemplary water sources
suitable for use in the present invention include, but are not
limited to, water from a municipal water source, or private water
system, e.g., a public water supply or a well. The water can be
city water, well water, water supplied by a municipal water system,
water supplied by a private water system, and/or water directly
from the system or well. The water can also include water from a
used water reservoir, such as a recycle reservoir used for storage
of recycled water, a storage tank, or any combination thereof. In
some embodiments, the water source is not an industrial process
water, e.g., water produced from a bitumen recovery operation. In
other embodiments, the water source is not a waste water
stream.
[0044] The methods, systems, apparatuses, and compositions of the
present invention can include, consist essentially of, or consist
of the components and ingredients of the present invention as well
as other ingredients described herein. As used herein, "consisting
essentially of" means that the methods, systems, apparatuses and
compositions may include additional steps, components or
ingredients, but only if the additional steps, components or
ingredients do not materially alter the basic and novel
characteristics of the claimed methods, systems, apparatuses, and
compositions.
[0045] As used herein, "weight percent," "wt-%," "percent by
weight," "% by weight," and variations thereof refer to the
concentration of a substance as the weight of that substance
divided by the total weight of the composition and multiplied by
100. It is understood that, as used here, "percent," "%," and the
like are intended to be synonymous with "weight percent," "wt-%,"
etc.
[0046] As used herein, the term "about" or "approximately" refers
to variation in the numerical quantity that can occur, for example,
through typical measuring and liquid handling procedures used for
making concentrates or use solutions in the real world; through
inadvertent error in these procedures; through differences in the
manufacture, source, or purity of the ingredients used to make the
compositions or carry out the methods; and the like. The term
"about" also encompasses amounts that differ due to different
equilibrium conditions for a composition resulting from a
particular initial mixture. Whether or not modified by the term
"about", the claims include equivalents to the quantities.
[0047] It should be noted that, as used in this specification and
the appended claims, the singular forms "a," "an," and "the"
include plural referents unless the content clearly dictates
otherwise. Thus, for example, reference to a composition containing
"a compound" includes a composition having two or more compounds.
It should also be noted that the term "or" is generally employed in
its sense including "and/or" unless the content clearly dictates
otherwise.
Water Hardness/Water Sources
[0048] In some aspects, the apparatuses and methods of the present
invention are used to treat a water source such that the
solubilized water hardness in the water source is controlled and/or
reduced. The water source treated may be any source of water having
a hardness that would be benefited by treatment in accordance with
the methods of the present invention. Exemplary water sources
suitable for treatment using the methods of the present invention
include, but are not limited to, ordinary tap water such as water
from a municipal water source, or private water system, e.g., a
public water supply or a well. The water can be city water, well
water, water supplied by a municipal water system, water supplied
by a private water system, and/or water directly from the system or
well. In some embodiments, the water source is not an industrial
process water, e.g., water produced from a bitumen recovery
operation. In other embodiments, the water source is not a waste
water stream.
[0049] The apparatus, systems and methods of the present invention
include treating a water source such that the solubilized hardness
of the water is controlled. In some aspects, the solubilized
hardness of the water is reduced. In some aspects, the present
invention provides methods for reducing or inhibiting scale
formation in an aqueous system.
[0050] In some embodiments, an aqueous system, i.e., a water
source, is contacted with one or more water treatment agents bound
to a resin and/or unbound conversion agents. Without wishing to be
bound by any particular theory, it is thought that the water
treatment agents cause solubilized calcium water hardness ions in
water to substantially precipitate via an interfacial reaction from
solution as calcium carbonate in the thermodynamically unfavorable
crystal form aragonite rather than as the thermodynamically
favorable crystal form calcite. Aragonite is a fragile crystal
which doesn't bind well to surfaces and doesn't form hard water
scale while calcite is a more robust crystal which binds tightly to
surfaces, forming a hard water scale that's not seen with
aragonite. Thus, contacting water with a water treatment agent of
the present invention reduces the solubilized water hardness of the
treated water, and leads to a reduction in scale formation on a
surface in contact with the treated water. The aragonite crystals
can also act as seed crystals for further reduction of solubilized
calcium after contacting the water treatment agent.
[0051] The methods of the present invention are especially
effective at removing or preventing scale formation wherein the
scale includes calcium salts, e.g., calcium phosphate, calcium
oxalate, calcium carbonate, calcium bicarbonate or calcium
silicate. The scale which is intended to be prevented or removed by
the present invention may be formed by any combination of the
above-noted ions. For example, the scale may involve a combination
of calcium carbonate and calcium bicarbonate.
[0052] In some embodiments the water source has a pH of between
about 6 and about 11 prior to treatment using the methods,
apparatuses, or systems of the present invention. In some
embodiments, the pH of the water source prior to treatment is
greater than about 8. In some embodiments, the pH of the water
source is raised to greater than 9, and in some embodiments the pH
is greater than 10 prior to treatment. In some embodiments, the pH
of the water source is increased prior to contacting the catalysts,
such as by injecting an alkaline chemical into the feedstream or by
applying a self-buffering alkali source, such as MgO or calcite, to
the water source. In some embodiments, the water source has a pH
greater than about 9 prior to treatment with the catalyst and the
precipitate does not need to be filtered because the formation of
large flocculent forms of precipitant is avoided. For example, more
than 200 ppm sodium carbonate (e.g., up to about 5,000 ppm) may be
added to the treated water source, raising the pH above about 10,
and the treated water would not need to be filtered.
Catalyst
[0053] Embodiments of the invention include a catalyst including a
support medium and a water treatment agent bound to the support
medium. The water treatment agent may be ionically bound or
physically bound to the support medium. The catalyst may be
contained within a treatment reservoir. In some embodiments, the
catalyst includes an additional functional ingredient which is not
bound to a support medium. In further embodiments, the catalyst
includes one or more water treatment agents bound to a support
medium and one or more additional functional ingredients which are
not bound to a support medium.
[0054] As used herein, the term "water treatment agent" refers to a
species that causes solubilized calcium in water to substantially
precipitate from solution as calcium carbonate in a form which is
thought to be the thermodynamically unfavorable crystal form
aragonite rather than as the thermodynamically favorable crystal
form calcite. Aragonite is a fragile crystal which doesn't bind
well to surfaces and doesn't form hard water scale while calcite is
a more robust crystal which binds tightly to surfaces, forming a
hard water scale that's not seen with aragonite.
[0055] Water treatment agents suitable for use with the methods and
apparatus of the present invention include sources of magnesium
ions, iron ions, aluminum ions, titanium ions, and zinc ions and
polymorphs of calcium. In some embodiments, the water treatment
agents suitable for use with the methods and apparatus of the
present invention do not include aluminum, zinc and/or titanium
ions. One or more water treatment agents may be used. In some
embodiments, the water treatment agent is selected from the group
consisting of sources of magnesium, aluminum, and titanium ions and
polymorphs of calcium. In some embodiments, the water treatment
agent includes only a source of magnesium ions.
[0056] While not intending to be bound by theory, it is believed
that the water treatment agents act as catalyst by acting as
nucleation seeds to precipitate calcium carbonate out of the water
in the form of aragonite. As such, the water treatment agent does
not undergo an ionic exchange which would require recharging of the
resin with new water treatment agent, as in existing water
treatment systems. Rather, the water treatment agent remains
adjoined to the catalyst and continues to promote the precipitation
of calcium carbonate over an extended period of time without
needing to be replaced for a long time. As aragonite precipitates
on the surface of the resin system it promotes further
precipitation of aragonite. As the resin column is agitated some of
the aragonite crystals are broken off the surface of the resin
system and mixed back into the water as precipitated seed crystals.
This process reaches a steady state so the rate of crystallization
equals the rate of removal from the surface.
[0057] Ongoing experiments have shown that the catalyst continues
to function after treating 25,000 gallons of water per pound of
resin without fail. In practice, the lifespan of the catalyst will
depend upon the water conditions and the presence of contaminants
in the water. In average water conditions, the catalyst may last 1
or 2 years, while in very good water conditions or in low water
usage rates it may last 5 or 10 years. In some embodiments, water
contacted with a water treatment agent forms a precipitate which
includes a cation which is different from the water treatment
agent. For example, in some embodiments the water treatment agent
includes a source of magnesium ions and the precipitate formed
includes calcium. In some embodiments, water contacted with a water
treatment agent forms a calcium precipitate. The calcium
precipitate formed using the methods of the present invention is
such that the precipitate (e.g. aragonite crystals) flows through
the water source harmlessly. That is, in some embodiments, unlike
conventional water treatment systems, there is not a need to filter
or remove the precipitate from the treated water.
[0058] The catalyst can further include additional functional
ingredients. Additional functional ingredients suitable for use
with the methods of the present invention include any materials
that impart beneficial properties to the catalyst, the water source
being treated, or any combination thereof. For example, functional
ingredients may be added that aid in the prevention of "cementing"
of the catalyst, i.e., agglomeration of the particles, as it is
contacted with a water source.
[0059] In some embodiments, the catalysts of the present invention
further include one or more additional functional ingredients
including, but not limited to, metal oxides, metal hydroxides,
polymorphs of calcium carbonate (non-Calcite forms) and
combinations and mixtures thereof. In some embodiments, the
additional ingredient includes one or more metal oxide, such as
magnesium oxide, aluminum oxide, and titanium oxide, for example.
In some embodiments, the additional functional ingredient includes
one or more metal hydroxide, such as magnesium hydroxide, aluminum
hydroxide, and titanium hydroxide, for example. Polymorphs of
calcium carbonate such as aragonite may also be used in embodiments
of the invention.
[0060] In some embodiments, the additional functional ingredient
used includes a metal oxide and a metal hydroxide in combination,
such as magnesium oxide and magnesium hydroxide. The additional
ingredients may be in any form, e.g., solid, particle, liquid,
powder, nanoparticle, slurry, suitable for use with the methods of
the present invention. In some embodiments, a solid source of an
additional functional ingredient is used.
[0061] In some embodiments, the catalyst includes a combination of
a water treatment agent bound to a support medium and an unbound
additional functional ingredient. For example, in one embodiment,
the catalyst includes magnesium bound to a support medium as well
as unbound additional ingredient such as magnesium oxide and/or
magnesium hydroxide. In some embodiments, the bound water treatment
agent and unbound additional ingredient are physically present
together, such as mixed together in the same treatment reservoir or
as separate layers in the same treatment reservoir. In other
embodiments, the bound water treatment agent and the unbound
additional ingredient are separate, such as in different treatment
reservoirs operating in series.
[0062] In some embodiments, the additional functional ingredient
includes a mixed cation compound of calcium and magnesium ions. In
some embodiments, the additional functional material includes
calcium magnesium carbonate, some natural minerals of which may
also be known by the name dolomite. In some embodiments, one or
more additional functional ingredients are bound to the supporting
material.
Supporting Material
[0063] In some aspects, the catalysts for use with the present
invention include a supporting material. The supporting material
may be any material to which a water treatment agent can be bound.
In some embodiments, the catalysts includes more than one different
supporting material.
[0064] In some embodiments, the supporting material has a density
slightly higher than the density of water to maximize fluidization
and/or agitation of the supporting material. In some embodiments,
the supporting material binds cations by ionic or electrostatic
force. In some embodiments, the bound cation is magnesium. In some
embodiments, the supporting material is inert.
[0065] In some embodiments, the water treatment agent includes a
resin. In some embodiments, the supporting material is a resin
capable of binding magnesium ions preferentially over binding
calcium ions. The resin for use as a supporting material can
include any ion exchange resin. For example, in some embodiments,
the resin includes an acid cation exchange resin, e.g., a weak acid
cation exchange resin, or a strong acid cation exchange resin. In
other embodiments, the supporting material is a chelating
resin.
[0066] In some embodiments, the resin includes an acrylic acid
polymer or methacrylic acid polymer. In some embodiments, the
supporting material is not inorganic. In some embodiments, the
supporting material comprises a polymer having sulfonic acid
substituents. For example, in some embodiments, the supporting
material does not include a ceramic material, and/or zeolites.
[0067] The supporting material may be provided in any shape and
size, including beads, sheets, rods, disks or combinations of more
than one shape.
[0068] The water treatment agent may be bound to the support
material in a variety of ways. For example, the resin may be loaded
with the magnesium resin by an ion exchange mechanism. In a
two-step process, the hydrogen on an acid resin is first exchanged
with sodium and then finally exchanged with the final cation using
the salt of the water treatment agent. For example, in some
embodiments, a magnesium bound resin catalyst may be created from a
weak acid cation exchange resin having a H+ ion attached to the
active sites, such as carboxylic acid groups. The weak acid cation
exchange resin can be first converted to a sodium form, such as by
soaking the resin in an excess of sodium hydroxide for 4 to 12
hours and then rinsing with water, and then the sodium form may be
converted to a magnesium form, such as by using soluble magnesium
salts, such as MgCl.sub.2 and MgSO.sub.4, for example.
[0069] Alternatively, the water treatment agent may be bound to the
supporting material using a one-step process. In some embodiments,
the magnesium may be directly exchanged with the hydrogen on the
surface of an acid resin. For example, the resin may be soaked in
an excess of magnesium salt, such as MgCl.sub.2 or MgSO.sub.4, for
a sufficient time such as 4 to 12 hours, and then rinsed with
water. Soluble magnesium salts which may be used include magnesium
chloride, magnesium sulfate, for example. In other embodiments, the
weak acid cation exchange resin may be converted to a magnesium
form using a low solubility magnesium source, such as magnesium
hydroxide, magnesium oxide, for example. For example, MgO can be
added to an apparatus containing a resin and either mixed with the
resin, or used as a separate pre-conditioning stage of the
apparatus. In some embodiments, magnesium is bound to the
supporting material using the one-step process using MgO or MgOH,
and some residual MgO or MgOH remain on the surface where they may
enhance the water treatment activity of the catalyst.
[0070] In other embodiments, the resin includes a weak acid cation
exchange resin having H+ ions attached to the active sites. The
resin may then be neutralized by having a water source run over it.
Without wishing to be bound by any particular theory, it is thought
that as the water runs over the resin, the calcium and magnesium
ions in the water will attach to the resin, thereby neutralizing
it.
[0071] Similar two step or one step processes could be used to bind
other water treatment agents such as aluminum, titanium, zinc, and
polymorphs of calcium, to the supporting material.
[0072] In some embodiments, a layer of a magnesium source may be
provided beneath an un-neutralized resin in a treatment reservoir,
so that when water flows through the reservoir, the catalyst is
converted to the magnesium form. For example, the reservoir is
first filled with the magnesium source (soluble or insoluble). The
un-neutralized resin is added on top of the magnesium source. When
the water starts to flow though the reservoir from the bottom up,
it picks up some of the magnesium and this material will react with
the resin to form the supported catalyst resin system.
[0073] The water treatment agent may be ionically or physically
bound to the supporting medium. For example, in some embodiments,
Ca2+ or Mg2+ have a loose ionic bond with a weak acid resin
substrate, providing a large amount of active surface area as the
ions are held loosely in there in ionic form and catalyzing the
precipitation of aragonite.
Treatment Reservoir
[0074] Embodiments of the invention include one or more treatment
reservoirs which contains the catalyst. Embodiments of the
invention include a system or apparatus having a single treatment
reservoir, one or more treatment reservoirs in parallel and/or one
or more treatment reservoirs in series. In embodiments which
include more than one treatment reservoir, each treatment reservoir
may include the same one or more catalysts or may include different
one or more catalysts. For example, the water source may be passed
over a plurality of reservoirs, in the same or in separate vessels,
including the same or different catalysis, i.e. water treatment
agents bound to a supporting material.
[0075] The treatment reservoir may be any shape or size appropriate
for the use of the water and the volume of water to be treated. In
some embodiments, the apparatus includes a vessel which includes a
treatment reservoir. The treatment reservoir may be for example, a
tank, a cartridge, a filter bed of various physical shapes or
sizes, or a column. In some embodiments, the treatment reservoir is
pressurized. In other embodiments, the treatment reservoir is not
pressurized.
[0076] Some embodiments of the invention include a treatment
reservoir including a water inlet and a water outlet. In some
embodiments, the water may enter and exit the treatment reservoir
through the same opening or channel. In some embodiments, the
treatment reservoir is contained within a vessel. Water to be
treated enters the vessel through an inlet located at or near the
top of a vessel, flows downward along the vessel wall or walls, and
enters the treatment reservoir at the bottom of the vessel. The
water flows upward through the treatment reservoir toward the top
of the vessel and exits the vessel through an outlet at or near the
top of the vessel.
[0077] An example of a system for treating water according to
embodiments of the invention is shown in FIG. 1, a schematic of an
apparatus of the present invention is shown at reference 10. The
apparatus includes: an inlet 12 for providing the water source to a
treatment reservoir 14; a treatment reservoir 14 including a water
treatment agent 16; an outlet 18 for providing treated water from
the treatment reservoir; and a treated water delivery line 20. In
some embodiments, the treated water delivery line 20 provides water
to a selected cleaning device. In some embodiments, there is no
filter between the outlet and the treated water delivery line. A
flow control device 22 such as a valve 24 can be provided in the
treated water delivery line 20 to control the flow of the treated
water into the selected end use device, e.g., a warewashing
machine, a laundry washing machine.
[0078] In some embodiments, the entire treatment reservoir can be
removable and replaceable. In other embodiments, the treatment
reservoir can be configured such that catalyst contained within the
treatment reservoir is removable and replaceable. In some
embodiments, the treatment reservoir includes a removable,
portable, exchangeable cartridge including a water treatment agent,
e.g., magnesium, bound to a supporting material, such as a weak
acid resin.
[0079] In some aspects, the present invention provides methods for
reducing or controlling solubilized water hardness and/or reducing
scale formation including contacting a water source with a catalyst
including a water treatment agent. The step of contacting can
include, but is not limited to, running the water source over or
through a solid source, e.g., a column, cartridge, or tank,
including the water treatment agent. The contact time is dependent
on a variety of factors, including, for example, the pH of the
water source, the hardness of the water source, and the temperature
of the water source.
[0080] In some embodiments, the catalyst is in the form of an
agitated bed or column. The bed or column can be agitated by any
known method including, for example, by the flow of water through
the column, fluidization, mechanical agitation or mixing, high flow
backwash, recirculation, air sparge, eductor flow, and combinations
thereof. In some embodiments, the catalyst includes a fluidized
bed, e.g., a column or a cartridge, in the treatment reservoir.
Fluidization is obtained by an increase in the velocity of the
fluid, e.g., water, passing through the bed such that it is in
excess of the minimum fluidization velocity of the media.
[0081] As the catalyst promotes precipitation of the calcium
carbonate, the calcium carbonate may be bound to the catalyst.
Therefore, the catalyst, such as the bed or column may be agitated
to avoid "cementing," i.e., agglomeration of the catalyst once
contacted with the water source. Such agitation may prevent the
precipitant from binding to the catalyst and/or may cause
precipitated calcium to become dislodged from the catalyst. For
example, as the aragonite precipitates on a catalyst, agitation of
the catalyst results the beads or granules of the support media,
for example, to bounce into each other and/or to bound into the
solid unbound conversion agent. The physical impact knocks off the
precipitate, such as aragonite crystals. The loose calcium
carbonate crystals may then pass through and exit the treatment
reservoir along with the treated water. In this way, the agitation
of the catalyst causes it to be self-cleaning, exposing the
catalyst and enabling it to continue nucleating and precipitating
the calcium carbonate from the water source. It has been discovered
that the catalyst according to embodiments of the invention can
continue to perform excellently on very hard water, such as 17
grain water, even after used to treat water for 900 consecutive
dishmachine cycles, with the inside of the dishmachine remaining
nearly perfect, whereas untreated was resulted in heavy scale
deposits.
[0082] The crystals are very small in size, are inert and
non-reactive, and do not stick to surfaces. For example, aragonite
crystals formed according to embodiments of the invention may be
between approximately 10 nm and 1000 nm in size. Because it is
inert and small in size, the precipitated calcium carbonate does
not need to be filtered or removed from the treated water. Rather,
the treated water containing the precipitated crystals of calcium
carbonate can be used for any downstream application.
[0083] The treatment reservoir may be contained in a vessel which
can be small, such as a canister filter-type vessel as used for
small drinking purification processes. Alternatively, the vessel
can be large, such as a large water treatment tank as used in whole
house water softening.
[0084] As water passes through the treatment reservoir, the water
treatment agent bound resin treats the water by nucleating and
precipitating calcium carbonate out of the water. In some
embodiments, the flow of water is in the upward direction. For
example, in some embodiments, the water enters the treatment
reservoir through an inlet in a bottom portion of the reservoir,
flows up through the catalyst, and exits the treatment reservoir
through an outlet at a top portion of the treatment reservoir.
[0085] The treatment reservoir may be sized and shaped to increase
the agitation and fluidization of the catalyst as water contacts
it. The agitation works to keep the catalyst clean from
precipitated calcium carbonate. In some embodiments, the volume of
the vessel is minimized, such that it contains only enough water
for the application or intended use such that the residence time is
not excessively low. This design prevents the water in the
reservoir from getting stagnant and reduces the possible risk of
bulk precipitation and accumulation of calcium carbonate in the
reservoir. In some embodiments, the volume of water in the vessel
may be completely evacuated with each use of the water. In some
embodiments, the vessel is sized such that there is sufficient
head-space (or free-board) above the resin to permit the resin to
rise and be agitated as water passes through. In some embodiments,
the free-board space is equal to approximately 100% of the volume
of the catalyst.
[0086] In some embodiments, the catalyst is agitated using
fluidization forces to create a flowing bed that is in constant
agitation when the water is flowing. In other embodiments, the
catalyst is agitated using centrifugal forces created by tangential
water flows, mechanical agitation, or ultrasound agitation, for
example. The agitation ultimately results in a cleaning of the
catalysts, removing the calcium crystals from the catalysts, such
that water can continue to flow over or through the media with
reduced obstruction.
Methods of Use
[0087] The methods, apparatuses, and systems of the invention may
be used for a variety of purposes. For example, an apparatus for
employing the water treatment methods of the present invention can
be connected to the water main of a house or business. The
apparatus can be employed in line before the hot water heater, or
after the hot water heater. Thus, an apparatus of the present
invention can be used to reduce solubilized water hardness in hot,
cold and room temperature water sources. In some embodiments, the
water to be treated in accordance with the present invention is at
a temperature of between about 10.degree. C. and about 90.degree..
In some embodiments, the temperature of the water to be treated is
above room temperature, e.g., greater than about 20.degree. C.
[0088] In some aspects, the present invention provides a system for
use in a cleaning process. The system includes providing a water
source to an apparatus for treating the water source. In some
embodiments, the apparatus for treating the water source includes:
(i) an inlet for providing the water source to a treatment
reservoir; (ii) a treatment reservoir containing a catalyst
including a water treatment agent bound to a supporting media
and/or an unbound additional functional ingredient; (iii) an outlet
for providing treated water from the treatment reservoir; and (iv)
a treated water delivery line for providing the treated water to
the automatic washing machine, such as a warewashing machine. In
some embodiments, a device, e.g., a screen, is present in the
treatment reservoir in order to keep the water treatment agent
contained within the treatment reservoir as the fluid is passing
over or through it. In some embodiments, the apparatus is
filterless, with no filter between the outlet and the treated water
delivery line.
[0089] Once the water has been treated, the treated water is
provided to an automatic washing machine, e.g., an automatic ware
washing or dishwashing machine, a vehicle washing system, an
instrument washer, a clean in place system, a food processing
cleaning system, a bottle washer, and an automatic laundry washing
machine, from the treated water delivery line of the apparatus.
Alternatively, the treated water may be used in a manual washing
system. Any automatic or manual washing machine that would benefit
from the use of water treated in accordance with the methods of the
present invention can be used. The treated water is then combined
with a detersive composition in the washing machine to provide a
use composition. Any detersive composition can be used in the
system of the present invention, for example, a cleaning
composition, a rinse agent composition or a drying agent
composition. The articles to be cleaned are then contacted with the
use solution in the automatic washing machine such that they are
cleaned.
[0090] The water treatment methods and systems of the present
invention can be used in a variety of industrial and domestic
applications. The water treatment methods and systems can be
employed in a residential setting or in a commercial setting, e.g.,
in a restaurant, hotel, hospital. For example, a water treatment
method, system, or apparatus of the present invention can be used
in: ware washing applications, e.g., washing eating and cooking
utensils and other hard surfaces such as showers, sinks, toilets,
bathtubs, countertops, windows, mirrors, and floors; in laundry
applications, e.g., to treat water used in an automatic textile
washing machine at the pre-treatment, washing, souring, softening,
and/or rinsing stages; in vehicle care applications, e.g., to treat
water used for pre-rinsing, e.g., an alkaline presoak and/or low pH
presoak, washing, polishing, and rinsing a vehicle; industrial
applications, e.g., cooling towers, boilers, industrial equipment
including heat exchangers; in food service applications, e.g., to
treat water lines for coffee and tea brewers, espresso machines,
ice machines, pasta cookers, water heaters, steamers and/or
proofers; in healthcare instrument care applications, e.g.,
soaking, cleaning, and/or rinsing surgical instruments, treating
feedwater to autoclave sterilizers; and in feedwater for various
applications such as humidifiers, hot tubs, and swimming pools
[0091] In some embodiments, the water treatment methods and systems
of the present invention can be applied at the point of use. That
is, a water treatment method, system, or apparatus of the present
invention can be applied to a water source upstream of an
application such as a washing system. In some embodiments, the
water treatment is applied immediately prior to the desired end use
of the water source. For example, an apparatus of the present
invention could be employed to a water line connected to a
household or restaurant appliance, e.g., a coffee maker, an
espresso machine, an ice machine. An apparatus employing the
methods of the present invention may be located in a washing
system. For example, it can also be included as part of an
appliance which uses a water source, e.g., a water treatment system
built into an automatic or manual washing system, a coffee maker,
an ice machine, or any other system which may benefit from the use
of treated water.
[0092] A treatment reservoir according to embodiments of the
invention may be used with a washing machine in a variety of ways.
In some embodiments, the treatment reservoir may be connected to a
detergent dispensing device. The treatment reservoir may be used to
supply treated water to a washing system and/or to a rinsing system
of a washing machine. In some embodiments, the treatment reservoir
may be used to supply a mixture of treated water and detergent to a
washing system.
[0093] Additionally, an apparatus for employing the water treatment
methods of the present invention can be connected to the water main
of a house or business. The apparatus can be employed in line
before the hot water heater, or after the hot water heater. Thus,
an apparatus of the present invention can be used to reduce
solubilized water hardness in hot, cold and room temperature water
sources.
[0094] Because the embodiments of the invention are so useful at
removing solubilized hardness from water, treated water may be used
with detergents having reduced amounts of builders or that are low
in builders. In some embodiments, the treated water may be used
with detergents which are substantially free of builders. In some
embodiments, the treated water may be used with detergents which
are substantially free of chelant, builder, threshold agent,
sequestrant or combinations thereof. Besides being economically
advantageous, the use of low builder detergents or no builder
detergents allowed by embodiments of the invention is also more
beneficial to the environment, as is the elimination of the need to
regenerate the system such as by using sodium chloride.
[0095] The methods, apparatuses, and systems of the present
invention may also be used in the food and beverage industry, for
example in a food and beverage processing application. In some
embodiments, the water treatment apparatuses can be used upstream
from a reverse osmosis membrane ("RO membrane"), a nanofiltration
system ("NF system"), or an ultrafiltration system ("UF system")
(collectively "RO/NF/UF systems") or an evaporator in a food or
beverage processing application, e.g., an application to treat whey
permeate.
[0096] For example, the methods and apparatuses can be used to
prevent calcium scale formation on evaporators and RO/NF/UF systems
used to process whey permeate, or other mineral containing feed
streams. Whey permeate contains water, lactose and minerals, e.g.,
calcium phosphate. The permeate is about 6% lactose and is
typically concentrated using RO filtration to reach about 18%
solids. The permeate is further concentrated using an evaporator to
reach about 65% solids. RO/NF/UF systems are known to be fouled by
the mineral, resulting in increased pressure for permeation and/or
a decreased flow rate.
[0097] During evaporation, the evaporator is fouled by mineral
deposits including mostly calcium phosphate scale. This scale
reduces heat transfer efficiency which in turn requires an increase
in steam and/or a decrease in feed flow rate to maintain the
finished solids content. Current scale reducing treatments include
adding polyphosphates to the feed stream to minimize scaling, and
using large amounts of acid to dissolve and remove the scale from
the RO/NF/UF units and evaporators. Using the apparatus, systems or
methods of the invention upstream from an RO/NF/UF system or an
evaporator may minimize the scaling and increase production
efficiency without having to use polyphosphate treatments or
treating the evaporator or RO/NF/UF units with a large amount of
acid to dissolve the scale.
[0098] In some embodiments, the methods and apparatus may also be
used to produce and isolate aragonite. Precipitates of aragonite
may be removed from the water by filtration, for example, and used
for industrial or pharmaceutical purposes.
EXAMPLES
Example 1
[0099] Three resin samples were prepared by loading them with H+,
Ca+, and Mg+. The magnesium loaded sample was prepared according to
the following procedure. A weak acid cation resin, Lewatit S 8528
obtained from the Lanxess Company, was soaked in 500 grams of NaOH
beads and 2500 ml of softened water for 24 hours. The pH was
approximately 12-13. After soaking, the resin was then rinsed
thoroughly with softened water three times until the pH of the
rinse water was below 11. The resin was soaked in 2500 ml of
softened water with 700 grams of a MgCl.sub.2.6H.sub.20 composition
for 4 days. The resin was thoroughly rinsed with softened water
three times. The final pH of the rinse water was approximately
7.5-8.5. To load the resin with Ca++, the same procedure was used
as the MG++ resin, only the resin was soaked with CaCl.sub.2
composition. The H+ form of the resin, was the resin itself,
without any cations loaded onto it.
[0100] The magnesium treated resin produced by this method was used
in Examples 3-5, below.
Example 2
[0101] The following alternative process was used to produce a
magnesium form of a weak acid cation exchange resin: Lewatit S 8528
resin was soaked in a 60% magnesium hydroxide slurry for 4 days.
The final pH of the rinse water was 11.0.
Example 3
[0102] Two pounds of the magnesium treated resin, produced
according to the method of Example 1, was used to treat 17 gpg
(grain per gallon) hard water. The two pounds of resin was placed
into a flow-through reservoir and connected to the inlet of an
institutional dishwashing machine. The treated water was then used
to wash test glasses in an AM-14 automatic ware washing machine
with no detergent and no rinse-aid. After 1100 cycles using the
same water treatment reservoir and resin, the interior of the
warewashing machine showed no visible scale.
[0103] FIG. 2 shows a picture of 8 test glasses, each washed in a
dishmachine using hard water treated with the magnesium catalyst
resin. The first six glasses from the left were removed from the
dishmachine after consecutive 100 cycles of the magnesium treated
resin and wash cycles of the glass. The sixth glass from the left,
after 600 cycles of the magnesium treated media and wash cycles,
showed no scale buildup. As can be seen, there was no scale buildup
on the glass even after 600 wash/rinse cycles while using the
magnesium treated resin. The seventh glass from the left was washed
100 times by the same magnesium treated resin after 800 cycles, and
the eighth glass from the left was washed 100 times by the same
magnesium treated resin after 900 cycles. As can be seen, even
after 900 cycles, there is no scale buildup, indicating that the
magnesium resin continued to reduce scaling even after 900
cycles.
Example 4
[0104] Magnesium treated resin, produced according to the method of
Example 1, was used to treat 17 Grain water. The water was treated
using a flow-through reservoir connected to a hard water tap. The
water was run through the reservoir to the drain and thus treated
continuously for over 15,000 gallons. After treating 15,803 gallons
of water, the reservoir was connected to an automatic ware washing
machine (Type AM-14) for 800 cycles with no detergent or rinse
aids. Following the 800 cycles, the interior of the ware washing
machine demonstrated no visible scale. As a comparison, untreated
17 Grain water was run through a ware washing machine (type AM-14)
for 800 cycles with no detergent or rinse aids. The interior of the
ware washing machine showed heavy scale. This indicates that the
resin bound magnesium continued to significantly reduce the soluble
hardness in the water even after treating 15,803 gallons of
water.
Example 5
[0105] Magnesium treated resin, produced according to the method of
Example 1, was used to treat 17 Grain water. The treated water was
used in an automatic ware washing machine with a detergent to wash
test glasses. The detergent was formulated with and without builder
according to table 1:
TABLE-US-00001 TABLE 1 Detergent Detergent with builder without
builder Raw Material (Approx. Wt. %) (Approx. Wt. %) Alkalinity
Source 10% 10% Builders 14% 0.0% Surfactants 4% 4% Soda Ash 67% 81%
Solvent 2% 2% Bleaching Agent 3% 3% 100.0% 100%
[0106] The results of this example are shown in FIGS. 3A-3D. In
FIG. 3A, the glasses were washed with the detergent without builder
and without water treatment and show heavy scale. In comparison, in
FIG. 3B, the glasses were washed with the same detergent without
builder and with water treated with magnesium bound resin, produced
according to the method of Example 1. These glasses had less scale
and looked better than the glasses washed in the untreated water.
This indicates that the use of the magnesium bound resin catalyst
reduced the need for builder in the detergent, even in 17 Grain
water.
[0107] The glasses in FIG. 3C were washed in untreated 17 Grain
water using the detergent including builder, while those in the
FIG. 3D were washed in the same detergent but using treated water
as described above with regard to FIG. 3B. The glasses in the FIG.
3C show a slight amount of scale, while the glasses in FIG. 3D have
no scale.
Example 6
[0108] Three resin samples were prepared by loading them with H+,
Ca++, and Mg++, according to the resin loading procedure described
in example 1. Water was then treated with each of the resin samples
and compared for scaling tendencies in a warewashing machine. The
feedwater to the dishmachine was thus treated with a H+ weak acid
cation resin, a Ca2+ weak acid cation resin, or a Mg2+ weak acid
cation resin in three separate but equivalent tests. Each of the
resin samples were first conditioned by running hard (17 gpg) water
through a flow-through reservoir to drain. After approximately 1000
gallons of water flow, the resin/reservoir systems were connected
to the dishmachine and evaluated for scaling tendencies on
glassware. The results of this comparison test are shown in FIG.
4A. After this dishmachine/glassware scaling test, the resin
samples were further conditioned by running hard water through a
flow-through reservoir to drain for an additional 4000 gallons and
therefore each resin had treated a total of about 5000 gallons of
water. A second set of dishmachine/glassware scaling tests were
then conducted, again without detergent and those results are shown
in FIG. 4B.
[0109] The control glasses (not shown) had heavy scale. The first
two glasses from the left in each FIGS. 4A and 4B were treated with
H+ bound resin. The third and fourth glass from the left in each
figure were treated with Ca2+ bound resin, and the fifth and sixth
glass from the left in each figure were treated with a Mg2+ bound
resin. As seen in FIG. 4A, the H+ resin and the Mg2+ resin showed
no visible scale in the test using resin that had previously
treated 1000 gallons of water. The two Ca2+ resin showed a clearly
visible scale. Referring to FIG. 4B, in which each of the resin
systems had previously treated 5000 gallons of water, the H+ resin
resulted in a slight scale on the glassware. The Ca2+ resin showed
a slightly heavier scale, and the Mg2+ resin showed little or no
visible scale.
Example 7
[0110] An experiment was performed to evaluate the effect of
various water treatment apparatuses on the metal content remaining
on a stainless steel surface after evaporation of whey permeate.
Whey permeate collected from a dairy plant was used for this
experiment. The water treatment apparatuses tested included resins
with varying water treatment agents contained in a vessel. The
following apparatuses were tested:
TABLE-US-00002 TABLE 2 Apparatus Number: Type 1 Control - 5 micron
filter that holds in resin beads 2 A magnesium loaded weak acid
cation resin that had previously treated 17 grain hard water. 3 A
protonated weak acid cation resin that had not previously treated
any water. 4 A magnesium loaded weak acid cation resin that had not
previously treated any water. 5 A protonated weak acid cation resin
rinsed with approximately 1000 milliliters of deionized (DI)
water.
[0111] For each resin, approximately 500 milliliters of permeate
was placed in the resin container and shaken for about 30 seconds.
The solutions where then allowed to drain through a resin support
filter into a beaker. Then, 100 milliliters of each of the treated
permeate was placed in separate stainless steel beakers. The
beakers were then placed in a 190.degree. F. to 195.degree. F.
water bath to initiate evaporation. After about 4.5 hours, the
solutions turned into a thick syrup like solution which was assumed
to be about 60-70% brix (60-70% sugar or other dissolved solids in
solution).
[0112] The beakers were removed from the water bath and rinsed with
DI water until the lactose sugary gel was removed, thereby leaving
only mineral deposits. The beakers were then rinsed with a 2% acid
solution to dissolve the mineral deposits. The acid used contained
phosphoric acid, so the phosphoric acid values of the rinsed
beakers were not considered meaningful in this experiment. The acid
solutions and controls were then submitted for Inductively Coupled
Plasma (ICP) testing for metal content. The tables below show the
results of this study.
TABLE-US-00003 TABLE 3 Treatment Resin Permeate After After
Apparatus Wt. Treated Initial % Treatment Initial Treatment Number
(g) (ml) Brix % Brix pH pH Observations Control - N/A N/A 6.3 N/A
5.43 N/A Clear yellow No solution Filtration End of test after DI
rinse, white mineral deposit remained. 1 N/A 500 6.3 6.5 5.43 5.51
Clear yellow solution End of test after DI rinse, white mineral
deposit remained 2 250 500 6.3 6.1 5.43 6.40 Clear yellow solution
after contact with resin Upon heating, a white precipitate formed
immediately End of test after DI rinse, beaker had slight bluing
residue 3 113 500 6.3 5.8 5.43 3.58 Cloudy and acidic after contact
with resin End of test after DI rinse, beaker looked clean 4 300
458 6.3 5.3 5.43 9.68 Clear yellow solution after contact with
resin During evaporation process, solution turned dark brown End of
test after DI rinse, beaker had slight bluing residue 5 113 500 6.3
5.5 5.43 3.93 Cloudy and less acidic after contact with resin End
of test after DI rinse, beaker looked clean.
TABLE-US-00004 TABLE 4 Treatment Apparatus Ca Mg P Na Number (ppm)
(ppm) (ppm) (ppm) Observations 1 609 101 507 514 Typical values for
a raw permeate control 2 269 553 358 311 pH increased slightly from
5.4 to 6.4 3 310 70.5 476 391 pH was much more acidic (3.6) after
resin treatment 4 6.05 73.6 371 2640 pH after resin was very
alkaline at 9.7 and brix dropped about 1% 5 287 67.5 436 384 Final
pH was still acidic at 3.9. Brix dropped about 0.8% after
treatment.
[0113] As can be seen from the above results, the whey treated with
Apparatus 2, which contained a magnesium loaded weak acid cation
resin, showed some decrease in the percent brix after treatment.
This indicates a decrease in lactose, mineral and/or organic
content in the treated sample.
[0114] Further, it was observed that the samples treated with
resins containing magnesium (Apparatuses 2 and 4) had a decreased
level of calcium remaining in the beaker. This decrease in calcium
may be due to a reduced amount of calcium from the permeate.
[0115] Overall, it was found that the use of water treatment
apparatuses according to embodiments of the present invention
resulted in a reduction in the amount of calcium insoluble salts in
this permeate evaporation test.
Other Embodiments
[0116] It is to be understood that while the invention has been
described in conjunction with the detailed description thereof, the
foregoing description is intended to illustrate, and not limit the
scope of the invention, which is defined by the scope of the
appended claims. Other aspects, advantages, and modifications are
within the scope of the following claims.
[0117] In addition, the contents of all patent publications
discussed supra are incorporated in their entirety by this
reference.
[0118] It is to be understood that wherever values and ranges are
provided herein, all values and ranges encompassed by these values
and ranges, are meant to be encompassed within the scope of the
present invention. Moreover, all values that fall within these
ranges, as well as the upper or lower limits of a range of values,
are also contemplated by the present application.
* * * * *