U.S. patent application number 11/067301 was filed with the patent office on 2006-08-31 for method for treating feedwater, feedwater treatment composition, and apparatus for treating feedwater.
Invention is credited to Michael E. Besse, William G. Mizuno, Brenda L. Tjelta, Ellen Voeller.
Application Number | 20060191851 11/067301 |
Document ID | / |
Family ID | 36468824 |
Filed Date | 2006-08-31 |
United States Patent
Application |
20060191851 |
Kind Code |
A1 |
Mizuno; William G. ; et
al. |
August 31, 2006 |
Method for treating feedwater, feedwater treatment composition, and
apparatus for treating feedwater
Abstract
A method for treating feedwater is provided. The method includes
steps of introducing a treatment composition into a feedwater
stream to provide a treated feedwater stream containing scale
inhibitor at a concentration of at least about 0.1 ppm, and
combining the treated feedwater stream with a detersive
composition. The scale inhibitor can include a phosphate scale
inhibitor, a carbonate scale inhibitor, or a combination of a
phosphate scale inhibitor and a carbonate scale inhibitor. The
detersive composition can be provided as a cleaning composition, a
rinse agent composition, or a drying agent composition. A treatment
composition and an apparatus for treating feedwater are
provided.
Inventors: |
Mizuno; William G.; (Golden
Valley, MN) ; Besse; Michael E.; (Golden Valley,
MN) ; Tjelta; Brenda L.; (St. Paul, MN) ;
Voeller; Ellen; (Golden Valley, MN) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Family ID: |
36468824 |
Appl. No.: |
11/067301 |
Filed: |
February 25, 2005 |
Current U.S.
Class: |
210/699 |
Current CPC
Class: |
C02F 1/72 20130101; C02F
5/10 20130101; C02F 1/70 20130101; C23F 14/02 20130101; B01J 23/16
20130101; C02F 1/66 20130101; C02F 2305/04 20130101; C02F 5/14
20130101; C02F 1/683 20130101; C02F 2103/02 20130101; C02F 1/56
20130101 |
Class at
Publication: |
210/699 |
International
Class: |
C02F 5/14 20060101
C02F005/14 |
Claims
1. A method for treating feedwater comprising: (a) introducing a
treatment composition into feedwater to provide treated feedwater
containing a scale inhibitor at a concentration of at least about
0.1 ppm; and (b) combining the treated feedwater stream with a
detersive composition to provide a use composition.
2. A method according to claim 1, wherein the treated feedwater
comprises the scale inhibitor at a concentration of about 0.1 ppm
to about 200 ppm.
3. A method according to claim 1, wherein the scale inhibitor
comprises carbonate scale inhibitor, phosphate scale inhibitor, or
mixture of carbonate scale inhibitor and phosphonate scale
inhibitor.
4. A method according to claim 3, wherein the treated feedwater
comprises about 1 ppm to about 100 ppm of a mixture of the
carbonate scale inhibitor and the phosphate scale inhibitor.
5. A method according to claim 3, wherein the phosphate scale
inhibitor comprises a polymer resulting from a reaction of an
olefinically unsaturated carboxylic acid monomer and
copolymerizable monomer comprising sulfonated monomer, nonionic
monomer, or mixture of sulfonated monomer and nonionic monomer.
6. A method according to claim 5, wherein the olefinically
unsaturated carboxylic acid monomer comprises a C.sub.3-C.sub.40
monocarboxylic acid, a C.sub.3-C.sub.40 dicarboxylic acid, or a
C.sub.3-C.sub.40 polycarboxylic acid.
7. A method according to claim 6, wherein the olefinically
unsaturated carboxylic acid monomer comprises an acid, a salt, or
an anhydride.
8. A method according to claim 6, wherein the olefinically
unsaturated carboxylic acid comprises acrylic acid, methacrylic
acid, ethacrylic acid, alpha-chloro-acrylic acid, alpha-cyano
acrylic acid, beta methyl-acrylic acid, alpha-phenylacrylic acid,
beta-acryloxy propionic acid, sorbic acid, alpha-chloro sorbic
acid, angelic acid, cinnamic acid, p-chloro cinnamic acid,
beta-styryl acrylic acid, itaconic acid, maleic acid, citraconic
acid, mesaconic acid, glutaconic acid, aconitic acid, fumaric acid,
or tricarboxyethylene, or mixture thereof.
9. A method according to claim 6, wherein the carboxylic monomer
comprises monoolefinic acrylic acid having a substituent selected
from hydrogen, halogen, hydroxyl, C.sub.1-C.sub.20 alkyl,
C.sub.6-C.sub.12 aryl, C.sub.6-C.sub.16 aralkyl, C.sub.7-C.sub.16
alkaryl, C.sub.5-C.sub.16 cycloaliphatic, or mixture thereof.
10. A method according to claim 1, wherein the scale inhibitor
comprises a carbonate scale inhibitor comprising phosphonate,
polycarboxylate, phosphinocarboxylate phosphonocarboxylate,
phosphinocaboxylate, or mixture thereof.
11. A method according to claim 1, further comprising: (a)
contacting the use composition with an article.
12. A method according to claim 11, wherein the article comprises
motor vehicle exterior, textile, food contacting article,
clean-in-place (CIP) equipment, hard surface, or mixture
thereof.
13. A method according to claim 1, wherein the scale inhibitor
comprises a mixture of carbonate scale inhibitor and phosphate
scale inhibitor at a weight ratio of the carbonate scale inhibitor
to the phosphate scale inhibitor of about 1:1 to about 1:10.
14. A method according to claim 11, further comprising: (a) rinsing
the use composition from the article.
15. A method according to claim 1, wherein the detersive
composition comprises a cleaning composition, a rinse agent
composition, or a drying agent composition.
16. A treatment composition comprising: (a) about 5 wt. % to about
95 wt. % of a scale inhibitor; (b) at least about 5 wt. % of: (i) a
solidifying agent to provide the treatment composition as a solid;
and (ii) a diluent to provide the treatment composition as a
flowable liquid.
17. A treatment composition according to claim 16, wherein the
treatment composition is provided as a solid and comprises about 10
wt. % to about 90 wt. % of the scale inhibitor and about 10 wt. %
to about 90 wt. % of the solidifying agent.
18. A treatment composition according to claim 16, wherein the
treatment composition is provided as a liquid and comprises about 5
wt. % to about 75 wt. % of the scale inhibitor and about 25 wt. %
to about 75 wt. % of the diluent.
19. A treatment composition comprising: (a) about 10 wt. % to about
100 wt. % of a scale inhibitor; and (b) the treatment composition
being provided in the form of a compressed block having a size of
about 1 pound to about 10 pounds.
20. A treatment composition according to claim 17, wherein the
solidifying agent comprises polyethylene glycol, a mixture of
polyethylene glycols, urea, or a salt of an alkaline metal
hydroxide
21. A treatment composition according to claim 18, wherein the
diluent comprises water.
22. An apparatus for treating feedwater comprising: (a) a feedwater
inlet for providing feedwater; (b) a treated feedwater outlet for
providing treated feedwater; (c) a treatment composition reservoir
comprising a treatment composition comprising a scale inhibitor;
and (d) a treatment composition delivery line for introducing the
treatment composition from the treatment composition reservoir into
the feedwater to provide the treated feedwater comprising about 0.1
ppm to about 200 ppm of the scale inhibitor.
23. An apparatus according to claim 23, further comprising a
venturi for drawing the treatment composition from the treatment
composition reservoir into the feedwater.
24. An apparatus according to claim 23, wherein the treatment
composition delivery line comprises a valve for controlling the
flow of the treatment composition into the feedwater.
25. An apparatus according to claim 22, further comprising a pump
for introducing the treatment composition from the treatment
composition reservoir into the feedwater.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method for treating
feedwater, a feedwater treatment composition, and an apparatus for
treating feedwater.
BACKGROUND OF THE INVENTION
[0002] A well-known problem in regions having hard water (i.e.,
water containing a high level of calcium or magnesium ions) is the
formation of scale deposits. Particularly in applications where
there are high levels of carbonate and/or phosphate ions, the
formation of Ca/Mg scales of these species can lead to buildup that
causes an unsightly residue ("film"). The terms "carbonate scale"
and "phosphate scale" refer to salts of carbonate and phosphonate
with calcium, magnesium, or other metal ions.
[0003] Carbonate scale and phosphate scale are particularly
troublesome in machine dishwashing applications because they have a
tendency to cause unsightly residues or films on dishware,
tableware, and especially glassware. This phenomenon is widely
known as "hard water film." In general, the presence of phosphates
and carbonates are desirable in machine dishwashing compositions
because of their cleaning power or building power. As a result,
"anti-filming technologies" to reduce the formation of carbonate
scale or phosphate scale resulting from automatic dishwashing have
been described in the literature.
[0004] Exemplary anti-filming technologies have utilized
polycarboxylates such as polyacrylates and polymethacrylates. See
U.S. Pat. No. 5,591,703. Polycarboxylate technologies assist in the
reduction of hard water filming in automatic dishwashing, as well
as in more general water treatment applications. Another class of
anti-filming materials to reduce phosphate and to some degree
carbonate scale is the sulfonate/carboxylate copolymers. See U.S.
Pat. No. 5,547,612 and U.S. Pat. No. 6,395,185. Commercially
available examples of sulfonate/carboxylate copolymers include
Alcosperse 240.TM. from Alco Chemical and Acusol 586.TM. from Rohm
and Haas Company. The copolymers can be derived from combinations
of sulfonate-containing and/or carboxylate-containing ethylenically
unsaturated monomers, such as acrylic acid, methylallylsulfonic
acid, ethoxylate esters of acrylic acids, and variations
thereof.
SUMMARY OF THE INVENTION
[0005] A method for treating feedwater is provided according to the
present invention. The method includes steps of introducing a
feedwater treatment composition into feedwater to provide treated
feedwater containing scale inhibitor at a concentration of at least
about 0.1 ppm, and combining the treated feedwater stream with a
detersive composition to provide a use composition. The use
composition can be applied to an article.
[0006] The scale inhibitor can include a phosphate scale inhibitor,
a carbonate scale inhibitor, or a combination of a phosphate scale
inhibitor and a carbonate scale inhibitor. The phosphate scale
inhibitor can include a polymer resulting from a reaction of an
olefinically unsaturated carboxylic acid monomer and at least one
of a copolymerizable sulfonated monomer, a copolymerizable nonionic
monomer, or a mixture of a copolymerizable sulfonated monomer and a
copolymerizable nonionic monomer. The carbonate scale inhibitor can
include phosphonates, polycarboxylates, phosphonocarboxylates, and
phosphinocarboxylates.
[0007] The detersive composition can include a cleaning
composition, a rinse agent composition, or a drying agent
composition. The treated feedwater composition can be combined with
the detersive composition.
[0008] A treatment composition is provided according to the present
invention. The treatment composition can include about 5 wt. % to
about 95 wt. % of a scale inhibitor and at least about 5 wt. % of a
solidifying agent to provide the treatment composition as a solid
or at least about 5 wt. % of a diluent to provide the treatment
composition as a flowable liquid. The treatment composition can be
provided as a solid or as a flowable liquid.
[0009] In an alternative embodiment of the present invention, the
treatment composition can be provided comprising about 10 wt. % to
about 100 wt. % of a scale inhibitor and can be provided in the
form of a compressed block having a size of about 1 pound to about
10 pounds.
[0010] An apparatus is provided according to the present invention.
The apparatus includes a feedwater inlet for providing feedwater, a
treated feedwater outlet for providing treated feedwater, a
treatment composition reservoir comprising a treatment composition,
and a treatment composition delivery line for introducing the
treatment composition from the treatment composition reservoir into
the feedwater to provide the treated feedwater.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic view of an apparatus for treating
feedwater according to the present invention.
[0012] FIG. 2 is a schematic view of an alternative embodiment of
an apparatus for treating feedwater according to the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] A feedwater treatment composition refers to a composition
that can be introduced into feedwater to provide treated feedwater.
The term "feedwater" refers to the water that is combined with a
detersive composition to provide a detersive use composition for
application to various articles. Detersive compositions are often
available as concentrates and require dilution to achieve a use
composition for application to various articles. Water that is
added as water of dilution can be referred to as feedwater. In
addition, the feedwater can be referred to as a "feedwater stream"
to refer to a continuous stream of water. The feedwater treatment
composition can be added to feedwater in a batch operation or in a
continuous operation. The reference to a "feedwater stream"
reflects a continuous operation and the reference to "feedwater"
can be batch or continuous.
[0014] Treated feedwater can be used the same way that feedwater is
used. That is, the treated feedwater can be combined with a
detersive composition to provide a detersive use composition, and
the detersive use composition can be used to treat articles.
Exemplary articles that can be treated with the detersive use
composition include motor vehicle exteriors, textiles, food
contacting articles, clean-in-place (CIP) equipment, and hard
surfaces. Exemplary motor vehicle exteriors include cars, trucks,
trailers, etc. that are commonly washed in commercial vehicle
washing facilities. Exemplary textiles include those textiles that
generally are considered within the term "laundry" and include
clothes, towels, sheets, etc. In addition, textiles include
curtains. Exemplary food contacting articles include dishes,
glasses, eating utensils, bowls, cooking articles, food storage
articles, etc. Exemplary CIP equipment include pipes, tanks, heat
exchangers, valves, distribution circuits, pumps, etc. Exemplary
hard surfaces include floors, counters, glass, walls, etc. In
general, hard surfaces can include those surfaces commonly referred
to in the cleaning industry as environmental surfaces.
[0015] The detersive composition refers to a composition that
provides cleaning properties, rinsing properties, or drying
properties. Exemplary detersive compositions include detergent
compositions, rinse agent compositions, or drying agent
compositions. Exemplary detergent compositions include warewashing
detergent compositions, laundry detergent compositions, CIP
detergent compositions, environmental cleaning compositions, hard
surface cleaning compositions (such as those for use on counters or
floors), motor vehicle washing compositions, and glass cleaning
compositions. Exemplary rinse agent compositions include those
compositions used to reduce streaking or filming on a surface such
as glass. Exemplary drying agent compositions include dewatering
compositions. In the vehicle washing industry, it is often
desirable to include a dewatering step where a sheeting or beading
agent is applied to the vehicle exterior.
[0016] After applying a detersive use composition to an article,
the article can be rinsed with a water rinse that is or is not
characterized as treated feedwater. For example, a water rinse can
be applied that is treated feedwater. Alternatively, a water inse
can be applied that is not treated feedwater. Water that has not
been treated with a feedwater treatment composition can be referred
to as "non-treated water."
[0017] The feedwater treatment composition can be referred to as
the "treatment composition." The feedwater treatment composition
includes a scale inhibitor to provide the resulting use composition
with scale inhibition properties. The scale inhibitor is provided
to reduce scaling that would result from components in the water,
components in the detersive composition, or components in both the
water and the detersive composition. Scaling can sometimes be
referred to as filming. Exemplary types of scaling include
carbonate scaling and phosphonate scaling. Carbonate scaling can
result from calcium bicarbonate in the water and alkalinity in the
detersive composition. Phosphate scaling typically results from
phosphate in the detersive composition. Phosphate is not a typical
species found in most natural water environments. Carbonate is
found in many detersive compositions, and is a reactor product of
soluble calcium bicarbonate water hardness with heat or alkalinity.
Exemplary types of scale inhibitors that can be included in the
treatment composition include carbonate scale inhibitors, phosphate
scale inhibitors or mixtures of carbonate scale inhibitors and
phosphate scale inhibitors. It is expected that other types of
scale inhibitors can be included in the treatment composition, if
desired, to handle the type of scaling that may be a problem in a
given application or environment.
[0018] By adding the scale inhibitor to the feedwater before the
detersive composition is added or introduced into the feedwater,
the scale inhibitor can be more effective in reducing scaling
compared to when the scale inhibitor is added as part of a
detersive composition. It is believed that certain scale inhibitors
can act as a threshold treatment agent to reduce scaling if they
are introduced into the water prior to introduction into the water
of scaling causing components in the detersive composition. The
phrase "threshold treatment agent" is meant to describe an activity
that can be characterized as substoichiometric. That is, the scale
inhibitor can be effective at concentration levels that are lower
than would be expected based on a stoichiometric equivalence of the
scale inhibitor and the scale causing component. One theory
explaining why the scale inhibitor can work better as a result of
being dissolved in the water prior to the introduction of the
detersive composition is that the scale inhibitor prevents or
reduces macrocrystalline growth. As a result, the scale inhibitor
can be used at a lower concentration than would be expected based
upon a stoichiometric amount to achieve the desired level of
chelation or sequestration.
[0019] Detersive compositions can be provided including one or more
scale inhibitor to address scaling in a particular application or
environment. It is believed that by providing the scale inhibitor
along with the detersive composition, the scale inhibitor is less
effective because it is generally not available to act
substoichiometrically. By introducing the scale inhibitor into the
feedwater before introduction of the detersive 110 composition into
the feedwater, it is believed that the scale inhibitor can be more
effective or successful in deterring scale formation because of its
ability to act substoichiometrically. In addition, because the
scale inhibitor can be effective at substoichiometric levels, it is
believed that significantly less scale inhibitor can be used to
achieve desired results when applied to feedwater prior to the
introduction of the detersive composition compared with the
introduction of the scale inhibitor along with the detersive
composition. It should be appreciated that these theories are just
that. They are theories proposed to explain the observation of
enhanced anti-scaling properties when the scale inhibitor are
introduced into the feedwater prior to introduction of the
detersive composition.
[0020] Because of the introduction of the scale inhibitor to the
feedwater prior to introduction into the feedwater of the detersive
composition, the detersive composition can be adjusted to remove or
reduce the scale inhibitor that may be present in the detersive
composition. By introducing the scale inhibitor into the feedwater
prior to introduction into the feedwater of the detersive
composition, less scale inhibitor can be used to achieve better
results and the scale inhibitor component of the detersive
composition can be removed.
[0021] The scale inhibitor can be provided as a carbonate scale
inhibitor, a phosphate scale inhibitor, or a combination of a
carbonate scale inhibitor and a phosphate scale inhibitor. In
addition, the scale inhibitor can include inhibitors directed at
scaling other than carbonate scale and phosphate scale.
[0022] In order to introduce the scale inhibitor into the
feedwater, numerous apparatus designs can be configured including
batch designs, continuous designs, and combination batch and
continuous designs. In the case of a batch design, the treatment
composition can be added to a body of water to provide treated
feedwater that can be used as desired. It is expected that a
continuous operation may be advantageous by allowing the treated
feedwater to be prepared as it is needed and without having to
create a storage tank for holding the treated feedwater. In a
continuous design, the scale inhibitor can be introduced into a
feedwater stream as the feedwater stream is being directed for
subsequent use. In addition, facilities can be retrofit to include
a feedwater treatment apparatus for continuous designs relatively
conveniently. FIGS. 1 and 2 provide alternative designs of
continuous feedwater treatment techniques.
[0023] Referring to FIG. 1, a schematic of an apparatus for
treating feedwater according to the present invention is shown at
reference number 10. The apparatus 10 includes a feedwater inlet
12, a treated feedwater outlet 14, a treatment composition
reservoir 16, and a treatment composition delivery line 18. In one
embodiment, an aspirator 20 can be used to draw the treatment
composition 22 from the treatment composition reservoir 16, through
the treatment composition delivery line 18, and into the feedwater
24. A flow control device 26 such as a valve 28 can be provided in
the treatment composition delivery line 18 to control the flow of
the treatment composition 22 into the feedwater 24. The aspirator
20 can be any type of aspirating device that draws another fluid
into a flowing liquid stream. The resulting treated feedwater 30
can be provided having a desired concentration of the treatment
composition therein.
[0024] Referring to FIG. 2, an alternative embodiment of an
apparatus for treating feedwater is shown at reference number 40.
The apparatus 40 includes a feedwater inlet 42, a treated feedwater
outlet 44, a treatment composition reservoir 46, and a treatment
composition delivery line 48. According to the apparatus 40, the
treatment composition 52 can be pumped into the feedwater 54 via
the treatment composition pump 56 to provide the treated feedwater
58. The treatment composition pump 56 can be any type of pump that
causes the treatment composition 52 to flow into the feedwater 54
so that the resulting treated feedwater 58 has the desired
concentration of the treatment composition 52 therein. Exemplary
pumps that can be used include proportioning pumps, peristaltic
pumps, piston pumps, bellows pumps, squeeze tube pumps, gear pumps,
etc.
[0025] An exemplary apparatus that can be used for treating
feedwater and that utilizes a venturi is described in U.S. Pat. No.
6,656,353 B2 to Kilawee et al. and assigned to Ecolab Inc., the
assignee of the above-identified patent application. The entire
disclosure of U.S. Pat. No. 6,656,353 B2 is incorporated herein by
reference.
[0026] The dispensing device disclosed in U.S. Pat. No. 6,656,353
B2 provides for dispensing of a chemical composition into water
flowing through a flow line. A portion of the water from the flow
line is diverted to contact a solid chemical composition and form a
liquid concentrate, and the liquid concentrate is drawn into the
water flow line as a result of a venturi action. Metering of the
liquid concentrate allows one to achieve the desired concentration
in the water.
Treatment Composition
[0027] The treatment composition can be available in various forms
including as a solid, a liquid, a gel, or paste. When provided as a
solid, the treatment composition can be provided in the form of a
block, pellets, aggregate, powder, capsules, tablets, etc. When
provided as a block, the treatment composition can have a size of
greater than about 1 pound. Providing the treatment composition as
a block can be advantageous when it is desired to periodically add
blocks to a hopper or other container where a liquid concentrate is
generated as a result of liquid flowing against a surface of the
block. When the treatment composition is provided as a block, the
block can have a size of at least about 1 pound. The block can be
provided having a size as large as desired for a particular
application. In many applications, it is expected that a block will
have a size of less than about 10 pounds although it should be
understood that the block can have a size that is much larger than
10 pounds. The block can have a size of between about 2 pounds and
about 6 pounds. Providing the treatment composition in various
other solid forms can be advantageous when it is desired to
generate a liquid concentrate that is then added to the feedwater
to provide treated feedwater.
[0028] The treatment composition includes a scale inhibitor. Other
components that can be included in the treatment composition
including hardening agents and diluents. Hardening agents can be
included to provide the treatment composition as a solid in the
form of a block, pellets, aggregate, capsule, tablet, etc. Diluents
can be included in the treatment composition to help maintain the
flowability of the treatment composition when it is provided in the
form of a liquid. In addition, diluent can be included when it is
desired to dilute the treatment composition when the treatment
composition is provided as a solid, liquid, gel, or paste. The
diluent can, if desired, be characterized as a filler.
[0029] The treatment composition can include the scale inhibitor in
an amount that provides a treatment composition having the desired
amount of scale inhibitor therein. For example, the treatment
composition can include about 0.1 wt. % to about 100 wt. % of the
scale inhibitor, and can include about 10 wt. % to about 100 wt. %
of the scale inhibitor. The scale inhibitor can include carbonate
scale inhibitor, phosphate scale inhibitor, or a mixture of a
carbonate scale inhibitor and a phosphate scale inhibitor. An
additional component of the treatment composition can be a
solidifying agent and/or a diluent. The solidifying agent can be
used to provide the treatment composition as a solid. It should be
understood that a treatment composition can be provided as a solid
without the use of a solidifying agent. For example, a treatment
composition containing 100 wt. % scale inhibitor can be compressed
into a tablet, a pellet, or a block. When compressed into a block,
it is expected that the block can have a size of about 1 pound to
about 10 pounds. The treatment composition can include a diluent to
provide the treatment composition in the form of a liquid. By way
of example, the treatment composition can include at least about 5
wt. % of the scale inhibitor and at least 5 wt. % of the
solidifying agent or the diluent. In addition, the treatment
composition can include about 5 wt. % to about 95 wt. % of the
scale inhibitor and about 5 wt. % to about 95 wt. % of the
solidifying agent or the diluent. In the case of a solid, the
treatment composition can include about 10 wt. % to about 90 wt. %
of the scale inhibitor and about 10 wt. % to about 90 wt. % of the
solidifying agent, and the treatment composition can include about
15 wt. % to about 85 wt. % of the scale inhibitor and about 15 wt.
% to about 85 wt. % of the solidifying agent. In the case of a
liquid treatment composition, the treatment composition can include
about 5 wt. % to about 75 wt. % of the scale inhibitor and about 25
wt. % to about 95 wt. % of the diluent, and the treatment
composition can include about 10 wt. % to about 60 wt. % of the
scale inhibitor and about 40 wt. % to about 90 wt. % of the
diluent.
[0030] It is desirable to provide the treated feedwater with a
concentration of scale inhibitor that is sufficient to provide a
desired level of scale inhibition. For example, the scale inhibitor
can be provided in the treated feedwater at a concentration of at
least about 0.1 ppm to achieve a desired level of scale inhibition.
The upper limit on the amount of scale inhibitor in the feedwater
composition can be provided based upon a decrease of scale
inhibition properties as the concentration of scale inhibitor
increases. In general, it may be desirable to avoid the cost
associated with adding additional scale inhibitor when the
increased amount of scale inhibitor fails to provide additional
scale inhibition properties. In general, it is expected that an
upper limit on the concentration of scale inhibitor in the treated
feedwater can be provided at about 200 ppm. The concentration of
scale inhibitor in the treated feedwater can be about 0.5 ppm to
about 150 ppm, about 1 ppm to about 100 ppm, and about 2 ppm to
about 50 ppm.
[0031] The scale inhibitor can include a carbonate scale inhibitor,
a phosphate scale inhibitor, or a combination of a carbonate scale
inhibitor and a phosphate scale inhibitor. In general, it is
believed that the presence of the carbonate scale inhibitor helps
reduce the occurrence of carbonate scaling as a result of the
presence of carbonate, and the presence of a phosphate scale
inhibitor helps reduce the occurrence of phosphate scaling as a
result of the presence of phosphate. The treatment composition can
include both a carbonate scale inhibitor and a phosphate scale
inhibitor, and can include one or more type of either or both of
the carbonate scale inhibitor and the phosphate scale
inhibitor.
Carbonate Scale Inhibitor
[0032] The carbonate scale inhibitor can be characterized as a
component that when introduced into feedwater, has an effective of
reducing carbonate scaling as a result of calcium bicarbonate that
may be present in the feedwater or alkalinity in the detersive
composition. Exemplary carbonate scale inhibitors include
phosphonates, polycarboxylates, or mixtures of phosphonates and
polycarboxylates. Exemplary phosphonates include
1-hydroxyethane-1,1-diphosphonic acid CH.sub.3C(OH) [PO(OH).sub.2;
aminotri(methylenephosphonic acid) N[CH.sub.2PO(OH).sub.2].sub.3;
aminotri(methylenephosphonate), sodium salt ##STR1##
2-hydroxyethliminobis(methylenephosphonic acid)
HOCH.sub.2CH.sub.2N[CH.sub.2PO(OH).sub.2].sub.2].sub.2;
diethylenetriaminepenta(methylenephosphonate), sodium salt
C.sub.9H.sub.(28-x)N.sub.3Na.sub.xO.sub.15P.sub.5 (x=7);
hexamethylenediamine(tetramethylenephosphonate), potassium salt
C.sub.10H.sub.(28-x)N.sub.2K.sub.xO.sub.12P.sub.4 (x=6);
bix(hexamethylene)triamine(pentamethylenephosphonic acid)
(HO.sub.2)POCH.sub.2N[(CH.sub.2).sub.6N[CH.sub.2PO(OH).sub.2].sub.2].sub.-
2; and phosphorus acid H.sub.3PO.sub.3. Exemplary polycarboxylates
include polyacrylic acid, polymaleic acid, maleic/olefin copolymer,
acrylic/maleic copolymer, polymethacrylic acid, acrylic
acid-methacrylic acid copolymers, hydrolyzed polyacrylamide,
hydrolyzed polymethacrylamide, hydrolyzed polyamide-methacrylamide
copolymers, hydrolyzed polyacrylonitrile, hydrolyzed
polymethacrylonitrile, hydrolyzed acrylonitrile-methacrylonitrile
copolymers. Phosphate Scale Inhibitor
[0033] Phosphate scale inhibitors that can be used include those
components that reduce phosphate scaling when introduced into a
feedwater prior to the introduction of a detersive composition
containing phosphate. It should be understood that many components
that provide phosphate scale inhibition may also provide some
carbonate scale inhibition. In addition, many of the components
identified as phosphate scale inhibitors can also be characterized
as carbonate scale inhibitors. Exemplary phosphate scale inhibitors
include polymers resulting from a reaction of an olefinically
unsaturated carboxylic acid monomer and a copolymerizable
sulfonated monomer, a copolymerizable nonionic monomer, or a
mixture of a copolymerizable sulfonated monomer and a
copolymerizable nonionic monomer.
[0034] The olefinically unsaturated carboxylic acid monomer can
include C.sub.3-C.sub.40, monocarboxylic acids, C.sub.3-C.sub.40
dicarboxylic acids, or C.sub.3-C.sub.40 polycarboxylic acids. The
olefinically unsaturated carboxylic acid monomer can be linear,
branched, or cyclic. The olefinically unsaturated carboxylic acid
monomer can be provided as a salt or an anhydride. Exemplary salts
include alkali metal salts, alkaline earth metal salts, and
ammonium salts. Exemplary olefinically unsaturated carboxylic acid
monomers include acrylic acid co-monomers such as acrylic acid,
methacrylic acid, ethacrylic acid, alpha-chloro-acrylic acid,
alpha-cyano acrylic acid, beta methyl-acrylic acid (crotonic acid),
alpha-phenylacrylic acid, beta-acryloxy propionic acid, sorbic
acid, alpha-chloro sorbic acid, angelic acid, cinnamic acid,
p-chloro cinnamic acid, beta-styryl acrylic acid
(1-carboxy-4-phenyl butadiene-1,3), itaconic acid, maleic acid,
citraconic acid, mesaconic acid, glutaconic acid, aconitic acid,
fumaric acid, and tricarboxyethylene. For the polycarboxylic acid
monomers, an anhydride group can be formed by the elimination of
one molecule of water from two carboxyl groups located on the same
polycarboxylic acid molecule. Exemplary carboxylic monomers include
monoolefinic acrylic acids having a substituent selected from the
class consisting of hydrogen, halogen, hydroxyl, C.sub.1-C.sub.20
alkyl, C.sub.6-C.sub.12 aryl, C.sub.6-C.sub.16 aralkyl,
C.sub.7-C.sub.16 alkaryl radicals and C.sub.5-C.sub.16
cycloaliphatic radicals. As used herein, (meth) acrylic acid is
intended to include acrylic acid and methacrylic acid. Preferred
unsaturated carboxylic acid monomers include acrylic and
methacrylic acid.
[0035] Exemplary copolymerizable sulfonated monomers include allyl
hydroxypropanyl sulfonate ether, allylsulfonic acid,
methallylsulfonic acid, styrene sulfonic acid, vinyl toluene
sulfonic acid, acrylamido alkane sulfonic acid, allyloxybenzene
sulfonic acid, 2-alkylallyloxybenzene sulfonic acid(s) such as
4-sulfophenol methallyl ether, and the alkali or alkaline earth
metal or ammonium salts thereof.
[0036] Exemplary copolymerizable nonionic monomers include vinyl or
allyl compounds selected from the group consisting of
C.sub.1-C.sub.6 alkyl esters of (meth)acrylic acid, acrylamide and
the C.sub.1-C.sub.6 alkyl-substituted acrylamides, the
N-alkyl-substituted acrylamides and the N-alkanol-substituted
acrylamides, N-vinyl pyrrolidone or any other vinyl amide. Also
useful are the C.sub.1-C.sub.6 alkyl esters and the C.sub.1-C.sub.6
alkyl half-esters of unsaturated vinylic acids, such as maleic acid
and itaconic acid. Exemplary copolymerizable nonionic monomers are
selected from the group consisting of methyl (meth)acrylate, mono-
and dimethyl maleate, mono- and di-ethyl itaconate, and (meth)allyl
acetates, propionates and valerates. Crosslinking monomers such as
diallyl maleate, alkylene bisacrylamide and triallyl cyanurate may
also be employed herein to provide crosslinking. It should be
understood that the term "acid" includes not only the acid function
but also corresponding anhydride and salt forms. The salts may be
alkali metals, alkaline earth metal, ammonium, and C.sub.2-C.sub.10
alkanolammonium types.
[0037] The polymer can be prepared based upon a ratio of the
olefinically unsaturated carboxylic acid monomer and the other
component including a copolymerizable sulfonated monomer, a
copolymerizable nonionic monomer, or a combination of a
copolymerizable sulfonated monomer and a copolymerizable nonionic
monomer in amounts sufficient to provide desired phosphate scale
inhibition. In general, the polymer can be prepared based upon
about 50 wt. % to about 99 wt. % of the olefinically unsaturated
carboxylic acid monomer. In addition, the polymer can be prepared
based upon about 70 wt. % to about 98 wt. % of the olefinically
unsaturated carboxylic acid monomer, and can be prepared based upon
about 75 wt. % to about 95 wt. % of the olefinically unsaturated
carboxylic acid monomer. In addition, the amount of the
copolymerizable sulfonated monomer, the copolymerizable nonionic
monomer, or the combination of copolymerizable sulfonated monomer
and copolymerizable nonionic monomer can be provided at about 1 wt.
% to about 50 wt. %, about 2 wt. % to about 30 wt. %, and about 5
wt. % to about 25 wt. %. The weight average molecular weight of the
polymers can be about 1500 to about 250,000, and can be from about
5,000 to about 100,000.
[0038] An exemplary phosphate scale-inhibiting copolymer includes a
tetrapolymer of 4-sulfophenol methallyl ether, sodium methallyl
sulfonate, acrylic acid, and methyl methacrylate. The monomer,
4-sulfophenol methallyl ether, has the formula (I):
CH.sub.2.dbd.C(CH.sub.3)CH.sub.2OC.sub.6H.sub.4SO.sub.3M (I) where
M represents hydrogen, alkali metal, alkaline earth metal or
ammonium ions. Other exemplary phosphate scale-inhibiting
copolymers include: copolymer of acrylic acid and 4-sulfophenol
methallyl ether; copolymer of acrylic acid and
2-acrylamido-2-methylpropane sulfonate; terpolymer of acrylic acid,
2-acrylamido-2-methylpropane sulfonate and sodium styrene
sulfonate; copolymer of acrylic acid and vinyl pyrrolicone; and a
copolymer of acrylic acid and acrylamide. Exemplary commercially
available copolymers that can be used as phosphate scale inhibitors
include: Alcosperse.RTM. 240, Aquatreat.RTM. AR 540 and
Aquatreat.RTM. MPS available from Alco Chemical; Acumer.RTM. 3100,
Acumer.RTM. 2100 and Acumer.RTM. 2000 available from Rohm and Haas
Company; Goodrich K-798, K-775 and K-797 available from BF
Goodrich; ACP 1042 available from ISP technologies, Inc.; and
polyacrylic acid/acrylamide available from Aldrich.
[0039] Phosphate and carbonate scale inhibitors can include
"phosphinoacrylic polymers" that result from the condensation of
low molecular weight, unsaturated monomers, such as those used to
form the acrylic polymers described above, with sodium
hypophosphite. For example, phosphinoacrylic polymers can have the
general formula:
H--[CH(CO.sub.2H)CH.sub.2].sub.nP-(.dbd.O)OH[CH.sub.2CH(CO.sub.2H)].sub.m-
.sup.-H wherein the molecular weight and ratio of propionic acid
units to the .sup.-P(.dbd.O)(OH)--unit may be varied over a wide
range. For example, n+m may vary from about 3 to about 75 and from
about 4 to about 70. Commercially available phosphinopolycarboxylic
acids having weight ratios of total polyacrylic acid to phosphinoxy
of from about 3:1 to 35:1 and molecular weights of about 200-5000,
preferably about 250-3000, are useful in the present invention. An
exemplary phosphinopolycarboxylic acid is available as
Belsperse.RTM. 161 from BioLabs as a 46-52% aqueous solution
(molecular weight of about 1200). Phosphinoacrylic polymers or
phosphinoacrylate polymers were developed by a division of
Ciba-Geigy and is now part of BioLabs. A Belsperse.RTM. 161 type
product is available from Buckman as BSI.RTM. 361, from Vulcan as
Mayosperse.RTM. 500 and from Rohm and Haas as Acumer.RTM. 4161.
[0040] When the treatment composition includes a mixture of a
carbonate scale inhibitor and a phosphate scale inhibitor, the
weight ratio of the carbonate scale inhibitor to the phosphate
scale inhibitor can be selected to provide the desired levels of
carbonate scale inhibition and phosphate scale inhibition. By way
of example, the weight ratio of the carbonate scale inhibitor to
the phosphate scale inhibitor can be about 1:1 to about 1:10.
Hardening Agent
[0041] The feedwater treatment composition can include a hardening
agent in an amount sufficient to provide the composition as a
solid. The hardening agent can be referred to as the solidifying
agent.
[0042] The feedwater treatment composition, when provided as a
solid, includes a sufficient amount of the hardening agent so that
the composition remains as a solid under conditions normally
encountered when storing the composition. In general, this means
that the solid should remain as a solid and resist melting during
transportation and storage. For example, the composition should be
capable of resisting melting at 120.degree. F. and atmospheric
pressure. The amount of the hardening agent will be sufficient so
that the feedwater treatment composition remains as a solid until
it is contacted with water. In the feedwater treatment composition,
the scale inhibitor is considered the active component of the
composition and it is generally desirable to provide as much of the
active component in the feedwater treatment composition as
possible.
[0043] An exemplary hardening agent includes polyethylene glycol.
Polyethylene glycol can be provided as a mixture of different
molecular weight polyethylene glycols. In general, when
polyethylene glycol is used as a hardening agent, it can be used in
an amount sufficient to provide hardening of the feedwater
treatment composition. For example, the amount of polyethylene
glycol in a hardened feedwater treatment composition can be
provided at least about 5 wt. %. In general, it is expected that
sufficient hardening can be provided at an amount of polyethylene
glycol that is less than about 55 wt. %. The solid detergent
composition can include about 8 wt. % to about 30 wt. %
polyethylene glycol. In addition, it should be understood that the
feedwater treatment composition can include mixtures of various
hardening agents and that the amount of polyethylene glycol, when
used with other hardening agents, may be relatively small as a
result of at least part of the hardening effect being contributed
by other agents.
[0044] An exemplary hardening agent includes urea. The feedwater
treatment composition can include a sufficient amount of urea to
provide the composition as a solid. In general, the amount of urea
in the composition can be at least about 5 wt. %. In addition, it
is generally expected that the hardening effect can be provided by
including an amount of urea at less than about 32 wt. %. The solid
composition can include urea at a composition of about 8 wt. % to
about 26 wt. %.
[0045] When the scale inhibitor is provided as an acid, a solid can
be formed by combining the acid with an alkaline metal hydroxide to
form an alkaline sale of the scale inhibitor. By way of example,
the scale inhibitor can be combined with the alkaline metal
hydroxide in amounts of about 10 wt. % to about 90 wt. % of the
scale inhibitor and about 10 wt. % to about 90 wt. % of the
alkaline metal hydroxide. In addition, the scale inhibitor can be
provided in an amount of about 15 wt. % to about 75 wt. % and the
alkaline metal hydroxide can be provided in an amount of about 15
wt. % to about 75 wt. %.
[0046] It should be understood that combinations of various
hardening agents can be used to provide a hardening effect. In the
case where combinations of different hardening agents are used, it
is expected that the amount of each of the types of hardening agent
may be less than would be necessary if that were the only hardening
agent used to provide the feedwater treatment composition as a
solid. In general, it is xpected that the feedwater treatment
composition can include a hardening agent in an mount of about 10
wt. % to about 90 wt. % to provide solid properties. In addition,
the mount of hardening agent can be provided in the feedwater
treatment composition in n amount of about 15 wt. % to about 90 wt.
%.
Diluent
[0047] A diluent can be included in the feedwater treatment
composition to help maintain stability or solubility of the
treatment composition. An exemplary diluent that can be provided in
the treatment composition includes water. In the case of a liquid
treatment composition, the amount of diluent can be provided up to
about 95 wt. %. In general, it is expected that if a diluent is
going to be used in the treatment composition, it can be included
in an amount of at least about 0.1 wt. %. In addition, fillers can
be included in the treatment composition and the fillers can be
characterized as a form of diluent. In the case of a solid
treatment composition, exemplary fillers that can be used include
potassium chloride, sodium chloride, and sodium sulfate. It is
expected that when the solid treatment composition includes a
filler, it will be included in the composition in an amount of at
least about 0.01 wt. % and can be provided in any amount to provide
the desired level of "fill." Exemplary upper amounts of filler in
the solid detergent composition can be, for example, 10 wt. %, 8
wt. %, or 5 wt. %.
[0048] In the case of a liquid treatment composition, a filler that
can be used includes water. When water is included in the liquid
treatment composition, it can be included in amounts up to about 95
wt. % and can be included in amounts of about 10 wt. % to about 80
wt. %, and about 25 wt. % to about 75 wt. %.
Other Components
[0049] The feedwater treatment composition can be used to provide a
treated feedwater stream for a detersive composition. The
Applicants have found that by introducing a scale inhibitor into
the feedwater prior to introduction of the chemicals normally
associated with a detersive composition, enhanced scale inhibition
can be achieved. The feedwater treatment composition can be
formulated so that the composition includes little or none of the
other components often encountered in a detersive composition. The
Applicants have found that getting the scale inhibitor into the
feedwater prior to introduction of a detersive composition into the
feedwater provides enhanced scale inhibition compared with
introducing the scale inhibitor as part of the detersive
composition. Accordingly, the feedwater treatment composition can
be provided so that components other than the scale inhibitor, the
solidifying agent, or the diluent can be limited. Exemplary
components that can be excluded from the treatment composition
include anti-redeposition agents, surface active agents or
surfactants, bleaching agents, brighteners, corrosion inhibitors,
and enzymes. If any of these components are present in the
treatment composition, they can be present at sufficiently low
levels. For example, the anti-redeposition agent can be excluded at
levels greater than 1 wt. %. The surface active agent or
surfactants can be excluded at levels greater than about 0.1 wt. %.
The bleaching agents can be excluded at levels greater than about
0.1 wt. %. The brightener can be excluded at levels greater than
about 0.1 wt. %. The corrosion inhibitor can be excluded at levels
greater than about 1 wt. %. The enzyme can be excluded at levels
greater than about 0.01 wt. %.
[0050] It is expected that by introducing the scale inhibitor into
the feedwater prior to introduction of the detersive composition
into the feedwater, it is expected that the detersive composition
can be adjusted to remove certain component that might have been
provided in the detersive composition for providing anti-filming
properties. Although the detersive composition can be adjusted in
view of the treatment to the feedwater, it is believed that the
detersive composition can be used as is if desired.
Detersive Composition
[0051] The treated feedwater stream can be combined with a
detersive composition to provide a detersive use composition. The
detersive composition refers to compositions that provide a
cleaning effect, a rinsing effect, or a drying effect. Compositions
that provide cleaning effect are often referred to as detergent
compositions. Compositions that provide rinsing effect are often
referred to as rinse agent or sheeting agent compositions.
Compositions that provide drying effect are often referred to as
drying agent compositions.
[0052] Detersive compositions often include various components such
as alkaline sources, surfactants, chelating/sequestering agents,
solvents, oxidizing agents, reducing agents, bleaching agents,
bleach activators, and enzymes. Examples of these components are
described. It should be understood that additional components can
be used in the detersive composition, when desired.
[0053] The detersive composition can include a source of alkalinity
to provide a detersive use composition having a desired pH.
Exemplary sources of alkalinity include the alkali metal
hydroxides, alkaline earth metal hydroxides, amine including the
alkylamines and ethanolamines, alkali metal carbonates or
bicarbonates, silicates, and so forth, and mixtures thereof.
[0054] A variety of surfactants can be used in the detersive
composition, including anionic, nonionic, cationic, and
zwitterionic surfactants, which are commercially available from a
number of sources. Anionic and nonionic agents are preferred. For a
discussion of surfactants, see Kirk-Othmer, Encyclopedia of
Chemical Technology, Third Edition, volume 8, pages 900-912.
Preferably, the detersive composition comprises a cleaning agent in
an amount effective to provide a desired level of cleaning. The
detersive composition can include about 0 to about 20 wt. %
cleaning agent, or about 1.5 wt. % to about 15 wt. % cleaning
agent.
[0055] Anionic surfactants useful in the present cleaning
compositions, include, for example, carboxylates such as
alkylcarboxylates (carboxylic acid salts) and
polyalkoxycarboxylates, alcohol ethoxylate carboxylates,
nonylphenol ethoxylate carboxylates; sulfonates such as
alkylsulfonates, alkylbenzenesulfonates, alkylarylsulfonates,
sulfonated fatty acid esters; sulfates such as sulfated alcohols,
sulfated alcohol ethoxylates, sulfated alkylphenols, alkylsulfates,
sulfosuccinates, alkylether sulfates; and phosphate esters such as
alkylphosphate esters. Exemplary anionics are sodium
alkylarylsulfonate, alpha-olefinsulfonate, and fatty alcohol
sulfates.
[0056] Nonionic surfactants useful in the detersive composition,
include those having a polyalkylene oxide polymer as a portion of
the surfactant molecule. Such nonionic surfactants include, for
example, chlorine-, benzyl-, methyl-, ethyl-, propyl-, butyl-, and
other alkyl-capped polyethylene glycol ethers of fatty alcohols;
polyalkylene oxide free nonionics such as alkyl polyglycosides;
sorbitan and sucrose esters and their ethoxylates; alkoxylated
ethylene diamine; alcohol alkoxylates such as alcohol ethoxylate
propoxylates, alcohol propoxylates, alcohol propoxylate ethoxylate
propoxylates, alcohol ethoxylate butoxylates; nonylphenol
ethoxylate, polyoxyethylene glycol ethers; carboxylic acid esters
such as glycerol esters, polyoxyethylene esters, ethoxylated and
glycol esters of fatty acids; carboxylic amides such as
diethanolamine condensates, monoalkanolamine condensates,
polyoxyethylene fatty acid amides; and polyalkylene oxide block
copolymers including an ethylene oxide/propylene oxide block
copolymer such as those commercially available under the trademark
PLURONIC (BASF-Wyandotte). Silicone surfactants such as the ABIL
B8852 can also be used.
[0057] Cationic surfactants useful for inclusion in a detersive
composition for sanitizing or fabric softening, include amines such
as primary, secondary and tertiary monoamines with C.sub.18 alkyl
or alkenyl chains, ethoxylated alkylamines, alkoxylates of
ethylenediamine, imidazoles such as a
1-(2-hydroxyethyl0-2-imidazoline, a
2-alkyl-1-(2-hydroxyethyl)-2-imidazoline; and quaternary ammonium
salts, as for example, alkylquaternary ammonium chloride
surfactants such as n-alkyl(C.sub.12-C.sub.18)dimethylbenzyl
ammonium chloride, n-tetradecyldimethylbenzylammonium chloride
monohydrate, and a naphthalene-substituted quaternary ammonium
chloride such as dimethyl-1-naphthylmethylammonium chloride.
[0058] Chelating/sequestering agents can provide water hardness
control in the alkaline wash solution, and more importantly, can
provide assistance in the soil removal process by interacting with
various calcium and magnesium complexes of both organic and
inorganic soil components. Water hardness ions can negatively
interfere with the cleaning process by forming less soluble
complexes with fatty acids or other surfactants.
Chelating/sequestering agents provide water hardness control by
interacting with water hardness ions such as calcium and magnesium
hydroxides, carbonates, sulfates, chlorides, and other ions which
are less soluble in alkaline solutions and which, upon exposure to
heat as during the dehydrating step, may precipitate from solution.
The chelating/sequestering agents thus help to keep the water
hardness ions in solution.
[0059] Any chelating/sequestering agents known to those in the art
may find utility herein. Examples of suitable
chelating/sequestering agents include, but are not limited to,
aminocarboxylic acids, condensed phosphates, phosphonates,
polyacrylates, alkali metal gluconates, citrates, etc.
[0060] In general, any chelating molecule which is capable of
coordinating (i.e., binding) the metal ions commonly found in
natural water to prevent the metal ions from interfering with the
action of the other detersive ingredients of a cleaning composition
may find utility herein. The chelating/sequestering agent may also
function as a threshold agent when included in an effective amount.
Preferably, a cleaning composition includes about 0.1-1 wt-%,
preferably from about 0.05-5 wt-%, of a chelating/sequestering
agent.
[0061] More particularly, suitable aminocarboxylic acids include,
for example, n-hydroxyethyliminodiacetic acid, nitrilotriacetic
acid (NTA), ethylenediaminetetraacetic acid (EDTA),
N-hydroxyethyl-ethylenediaminetri-acetic acid (HEDTA),
diethylenetriaminepentaacetic acid (DTPA), and the like.
[0062] Suitable examples of condensed phosphates useful in the
present composition include sodium and potassium orthophosphate,
sodium and potassium pyrophosphate, sodium tripolyphosphate, sodium
hexametaphosphate, and the like. A condensed phosphate may also
assist, to a limited extent, in solidification of the composition
by fixing the free water present in the composition as water of
hydration.
[0063] For a further discussion of chelating agents/sequestrants,
see Kirk-Othmer, Encyclopedia of Chemical Technology, Third
Edition, volume 5, pages 339-366 and volume 23, pages 319-320, the
disclosure of which is incorporated by reference herein.
[0064] Solvents that may be used in detersive compositions include
glycol ethers, alcohols, esters such as soy methyl ester, acetates,
cyclic acids, and mixtures thereof.
[0065] Oxidizing agents that may be used in detersive compositions
include the alkali metal hypochlorites such as sodium and potassium
hypochlorite, chlorine dioxide solutions, various peracids, and
mixtures thereof.
[0066] Reducing agents that may be used in detersive compositions
include the alkali metal thiosulfates such as sodium thiosulfate,
the alkali metal sulfites such as sodium sulfite, the alkali metal
metabisulfites such as sodium metabisulfite, and mixtures
thereof.
[0067] Bleaching agents that may be used in detersive compositions
include compounds which release halogens (e.g. Cl, Br, OCl and/or
OBr) under the conditions encountered during the cleansing process
such as a chlorine, hypochlorite, chloramine, alkali metal
dichloroisocyanurates, chlorinated trisodium phosphate, the alkali
metal hypochlorides, monochloramine and dichloramine, and the like
and the bromine releasing compounds as well.
[0068] Oxygen bleaching agents may also be employed including the
peroxygen type or active oxygen source such as hydrogen peroxide,
organic and inorganic peroxohydrates, organic peroxyacids including
peroxycarboxylic, peroxyimidic and amidoperoxycarboxylic acids, or
their salts including alkali metal or mixed-cation salts,
perborates, sodium carbonate peroxyhydrate, phosphate
peroxyhydrates, potassium permonosulfate, and sodium perborate mono
and tetrahydrate, with and without activators such as
tetraacetylethylene diamine, peracids which can be employed both as
free standing and as bleach activators, inorganic peroxides,
inorganic peroxoacids and their salts, certain organic peroxides,
and the like, and mixtures thereof.
[0069] Bleach activators known in the art may be used in detersive
compositions to activate bleaches. Exemplary bleach activators
include, for example, tetraacetyl ethylene diamine (TAED), sodium
nonanoyloxybenzene sulphonate (SNOBS), glucose pentaacetate (GPA),
tetra acetylmethylene diamine (TAMD), triacetyl cyanurate, sodium
sulphonyl ethyl carbonic acid ester, sodium acetyloxybenzene and
the mono long-chain acyl tetraacetyl glucoses as disclosed in WO
91/10719 incorporated by reference herein in its entirety, choline
sulphophenyl carbonate (CSPC) can also be employed, as disclosed in
U.S. Pat. Nos. 4,751,015 and 4,818,426 both of which are
incorporated by reference herein in their entirety.
EXAMPLE 1
[0070] A product was manually added to the rinse water or the
initial water charge (feedwater) of a dishwashing machine. The
dishwashing machine used was an AM-14 high temperature dishwashing
machine from Hobart. The product was added to the dishwashing
machine to treat any additional water that was added during a
cycle.
Exemplary products include:
Dequest 2000 (ATMP--aminotrimethylene phosphonic acid (50%
active))
Dequest 2010 (HEDP-1-hydroxyethylene-1,1-diphosphnic
acid-hydroxyethylidene diphosphonic acid (60% active))
Optidose 4210 (polymaleic acid, molecular weight 500-1,000, 50%
solids)
Alcoguard 4000 (sulfonated polymer)
Alcosperse 240 (copolymer of acrylic acid and sulfonated
monomers)
Alcosperse 747 (modified polycarboxylate)
Accusol 587 (weak acid/strong acid (sulfonic) copolymer)
Accusol 586 (weak acid/strong acid (sulfonic) copolymer)
[0071] The detergent composition used in the dishwashing machine
was a high alkaline solid containing sodium tripolyphosphate and
sodium carbonate. The tests were run for 100 cycles on six glasses.
The grading system for the glasses is based on a scale of 1-5 where
1 means no film, 2 means trace film, 3 means light film, 4 means
medium film, and 5 means heavy film. The results of the experiment
are reported in Table 1. TABLE-US-00001 TABLE 1 Glass Component 1 2
3 4 5 6 Total None (Control) 5 3.5 3 3 3 5 22.5 Optidose 4210
product 3.5 2.5 1.5 1.5 2 3.5 14.5 Alcoguard 4000 product 3.75 1.5
1.5 1.5 1.5 4 13.75
[0072] The Optidose 4210 product and the Alcoguard 4000 product
were used at levels of 5 ppm and 10 ppm, respectively. When the
Optidose 4210 product and the Alcoguard 4000 product were used to
treat all of the water entering the dishwashing machine, there was
significant improvement in filming of the glasses as compared to
the control.
EXAMPLE 2
[0073] An exemplary liquid feedwater treatment composition was
prepared having the following components:
31.2 wt. % Dequest 2010 product
31.2 wt. % Alcosperse 240 product
37.6 wt. % water.
[0074] A solid feedwater treatment composition was prepared having
the following components:
41.5 wt. % Alcoguard 4000
41.5 wt. % Dequest 2010
17 wt. % sodium hydroxide.
[0075] A solid feedwater treatment composition was prepared
including a carbonate scale inhibitor and having the following
components:
68.5 wt. % Dequest 2010
31.5 wt. % sodium hydroxide.
* * * * *