Patent US4029577A successfully refreshed from Google Patents.
US4029577A
Expired / Lapsed
US
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Polymers for use in water treatment
Assignee: Veolia WTS USA Inc
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Filing: 1975-11-17
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Granted: 1977-06-14
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Expires: 1995-11-17
Abstract
Abstract The present invention relates to processes for controlling the formation and deposition of scale and/or suspended solid matter which otherwise would occur in aqueous mediums containing scale imparting ions and dispersed particles. The invention, more particularly, relates to the control of the formation of, the reduction and/or the prevention of the deposition of calcium phosphate, magnesium silicate and/or iron oxide, clay and mixtures thereof in cooling water, scrubber and steam generating systems, evaporators, economisers and the like by the introduction of an effective amount for the purpose of a water soluble polymer composed primarily of moieties derived from acrylic acid or water soluble salt thereof and hydroxy lower alkyl acrylate moieties or water soluble salt thereof to the water used therein. The polymers discovered to be effective for the purpose are those preferably having a mole ratio of from about 34 : 1 to about 1 : 4 of acrylic acid to hydroxylated lower alkyl acrylate moieties. The lower alkyl is an alkyl of from 2 to 6 carbon atoms.
Inventors
- 👤 Irene T. Godlewski
- 👤 Joseph J. Schuck
- 👤 Bruce L. Libutti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:38
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
158 words
A method of controlling the deposition of scale imparting precipitates on the structural parts of a system exposed to an aqueous medium containing scale imparting precipitates under deposit forming conditions; said scale imparting precipitates being selected from the group consisting of calcium phosphate, magnesium phosphate, calcium silicate, magnesium silicate, iron oxide and mixtures thereof, which method comprises adding to said aqueous medium an effective amount for the purpose of a water soluble polymer comprising moieties derived from an acrylic acid or water soluble salt thereof and moieties of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formulas: ##STR4## wherein R is hydrogen or a lower alkyl of from 1 to 3 carbon atoms; R 1 is OH, OM or NH 2 where M is a water soluble cation; R 2 is a lower alkyl of from about 2 to 6 carbon atoms and the mole ratio of x:y is 34:1 to 1:4.
Claim 2
Independent Claim
158 words
A method of controlling the deposition of scale imparting precipitates on the structural parts of a system exposed to an aqueous medium containing scale imparting precipitates under deposit forming conditions; said scale imparting precipitates being selected from the group consisting of calcium phosphate, magnesium phosphate, calcium silicate, magnesium silicate, iron oxide and mixtures thereof, which method comprises adding to said aqueous medium an effective amount for the purpose of a water soluble polymer comprising moieties derived from an acrylic acid or water soluble salt thereof and moieties of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formulas: ##STR4## wherein R is hydrogen or a lower alkyl of from 1 to 3 carbon atoms; R 1 is OH, OM or NH 2 where M is a water soluble cation; R 2 is a lower alkyl of from about 2 to 6 carbon atoms and the mole ratio of x:y is 34:1 to 1:4.
Claim 3
Dependent Claim
38 words
A method according to claim 1, wherein the polymer has a molecular weight of from about 500 to 1,000,000 and is added in an amount of from about 0.1 to 500 parts per million parts of aqueous medium.
Claim 4
Dependent Claim
14 words
A method according to claim 2, wherein the system is a steam generating system.
Claim 5
Dependent Claim
26 words
A method according to claim 2, wherein the polymer is a copolymer of acrylic acid or water soluble salt thereof and 2-hydroxypropyl acrylate or hydroxyethyl acrylate.
Claim 6
Dependent Claim
27 words
A method according to claim 4, wherein the mole ratio of acrylic acid or water soluble salt thereof to the acrylate is from about 11:1 to 1:2.
Claim 7
Dependent Claim
14 words
A method according to claim 5, wherein the system is a steam generating system.
Claim 8
Independent Claim
137 words
A method of dispersing and maintaining dispersed particulate matter in a system having an aqueous medium which contains particulate matter selected from the group consisting of clay, iron oxide and mixtures thereof, which method comprises adding to the aqueous medium an effective amount for the purpose of a water soluble polymer comprising moieties derived from an acrylic acid or water soluble salt thereof and moieties of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formulas: ##STR5## wherein R is hydrogen or a lower alkyl of from 1 to 3 carbon atoms; R 1 is OH, OM or NH 2 where M is a water soluble cation; R 2 is a lower alkyl of from about 2 to 6 carbon atoms and the mole ratio of x:y is 34;1 l to 1:4.
Claim 9
Independent Claim
137 words
A method of dispersing and maintaining dispersed particulate matter in a system having an aqueous medium which contains particulate matter selected from the group consisting of clay, iron oxide and mixtures thereof, which method comprises adding to the aqueous medium an effective amount for the purpose of a water soluble polymer comprising moieties derived from an acrylic acid or water soluble salt thereof and moieties of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formulas: ##STR5## wherein R is hydrogen or a lower alkyl of from 1 to 3 carbon atoms; R 1 is OH, OM or NH 2 where M is a water soluble cation; R 2 is a lower alkyl of from about 2 to 6 carbon atoms and the mole ratio of x:y is 34;1 l to 1:4.
Claim 10
Dependent Claim
38 words
A method according to claim 7, wherein the polymer has a molecular weight of from about 500 to 1,000,000 and is added in an amount of from about 0.1 to 500 parts per million parts of aqueous medium.
Claim 11
Dependent Claim
26 words
A method according to claim 8, wherein the polymer is a copolymer of acrylic acid or water soluble salt thereof and 2-hydroxypropyl acrylate or hydroxyethyl acrylate.
Claim 12
Dependent Claim
27 words
A method according to claim 9, wherein the mole ratio of acrylic acid or water soluble salt thereof to the acrylate is from about 11:1 to 1:2.
Claim 13
Dependent Claim
14 words
A method according to claim 10, wherein the system is a cooling water system.
Claim 14
Dependent Claim
13 words
A method according to claim 10, wherein the system is a scrubber system.
Claim 15
Dependent Claim
14 words
A method according to claim 8, wherein the system is a cooling water system.
Claim 16
Dependent Claim
13 words
A method according to claim 8, wherein the system is a scrubber system.
Claim 17
Dependent Claim
14 words
A method according to claim 7, wherein the system is a cooling water system.
Claim 18
Dependent Claim
13 words
A method according to claim 7, wherein the system is a scrubber system.
Claim 19
Independent Claim
133 words
A method of inhibiting the formation of calcium phosphate in a system which contains an aqueous medium having calcium and phosphate scale forming ions under calcium phosphate forming conditions, which method comprises adding to the aqueous medium an effective amount for the purpose of a water soluble polymer comprising moieties derived from an acrylic acid or water soluble salt thereof and moieties of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formulas: ##STR6## wherein R is hydrogen or a lower alkyl of from 1 to 3 carbon atoms; R 1 is OH, OM or NH 2 where M is a water soluble cation; R 2 is a lower alkyl of from about 2 to 6 carbon atoms and the mole ration of x:y is 34:1 to 1:4.
Claim 20
Independent Claim
133 words
A method of inhibiting the formation of calcium phosphate in a system which contains an aqueous medium having calcium and phosphate scale forming ions under calcium phosphate forming conditions, which method comprises adding to the aqueous medium an effective amount for the purpose of a water soluble polymer comprising moieties derived from an acrylic acid or water soluble salt thereof and moieties of an hydroxylated lower alkyl acrylate, wherein the moieties of the polymer have the following formulas: ##STR6## wherein R is hydrogen or a lower alkyl of from 1 to 3 carbon atoms; R 1 is OH, OM or NH 2 where M is a water soluble cation; R 2 is a lower alkyl of from about 2 to 6 carbon atoms and the mole ration of x:y is 34:1 to 1:4.
Claim 21
Dependent Claim
38 words
A method according to claim 17, wherein the polymer has a molecular weight of from about 500 to 1,000,000 and is added in an amount of from about 0.1 to 500 parts per million parts of aqueous medium.
Claim 22
Dependent Claim
14 words
A method according to claim 18, wherein the system is a cooling water system.
Claim 23
Dependent Claim
20 words
A method according to claim 19, wherein the phosphate ions have been added to the aqueous medium as a treatment.
Claim 24
Dependent Claim
26 words
A method according to claim 18, wherein the polymer is a copolymer of acrylic acid or water soluble salt thereof and 2-hydroxypropyl acrylate or hydroxyethyl acrylate.
Claim 25
Dependent Claim
28 words
A method according to claim 21, wherein the mole ratio of the acrylic acid or water soluble salt thereof to the acrylate is from about 11:1 to 1:2.
Claim 26
Dependent Claim
14 words
A method according to claim 22, wherein the system is a cooling water system.
Claim 27
Dependent Claim
20 words
A method according to claim 23, wherein the phosphate ions have been added to the aqueous medium as a treatment.
Claim 28
Dependent Claim
14 words
A method according to claim 21, wherein the system is a cooling water system.
Claim 29
Dependent Claim
20 words
A method according to claim 25, wherein the phosphate ions have been added to the aqueous medium as a treatment.
Claim 30
Dependent Claim
20 words
A method according to claim 17, wherein the phosphate ions have been added to the aqueous medium as a treatment.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-13 | 1980-12-13 | 1981-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-13 | 1984-12-13 | 1985-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-13 | 1988-12-13 | 1989-06-14 | $7700.00 | Window Closed / Lapsed |