Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
157 words
A method of treating an aqueous system containing calcium ions and suspended soli to inhibit scale deposition, prevent fouling disperse said suspended solids, and inhibit corrosion of metals in contact therewith, which comprises adding to the system a water-soluble tri-copolymer having the formula I: (A).sub.x (B).sub.y (C).sub.z I or a salt thereof, wherein A is a group having the formula ##STR3## or a hydrolysed (dicarboxylic acid or salt) form of this group; B is ethyl acrylate; C is styrene or 1-decene, and x, y and z are integers, so chosen that (1) the molar ratio of A in the tri-copolymer ranges from 30 to 80% by weight; the molar ratio of B in the tri-copolymer ranges from 10 to 40% by weight; and the molar ratio of C in the tri-copolymer ranges from 10 to 30% by weight; and (2) the weight average molecular weight of the tri-copolymer is within the range of from 600 to 10,000.
Claim 2
Independent Claim
157 words
A method of treating an aqueous system containing calcium ions and suspended soli to inhibit scale deposition, prevent fouling disperse said suspended solids, and inhibit corrosion of metals in contact therewith, which comprises adding to the system a water-soluble tri-copolymer having the formula I: (A).sub.x (B).sub.y (C).sub.z I or a salt thereof, wherein A is a group having the formula ##STR3## or a hydrolysed (dicarboxylic acid or salt) form of this group; B is ethyl acrylate; C is styrene or 1-decene, and x, y and z are integers, so chosen that (1) the molar ratio of A in the tri-copolymer ranges from 30 to 80% by weight; the molar ratio of B in the tri-copolymer ranges from 10 to 40% by weight; and the molar ratio of C in the tri-copolymer ranges from 10 to 30% by weight; and (2) the weight average molecular weight of the tri-copolymer is within the range of from 600 to 10,000.
Claim 3
Dependent Claim
70 words
Method according to claim 1, wherein the aqueous system is treated to impart corrosion inhibition to metal surfaces in contact with the system, or is treated to impart corrosion inhibition to metal surfaces in contact with the system with simultaneous scale-inhibiting treatment and the amount of the tri-copolymer of formula I added is within the range of from 0.1 to 50,000 ppm, based on the weight of the aqueous system.
Claim 4
Dependent Claim
29 words
Method according to claim 2 wherein the amount of the tri-copolymer of formula I added is from 1 to 500 ppm, based on the weight of the aqueous system.
Claim 5
Dependent Claim
40 words
Method according to claim 1 wherein the aqueous system is treated solely to inhibit scale formation and the amount of the tri-copolymer of formula I added is from 1 to 200 ppm, based on the weight of the aqueous system.
Claim 6
Dependent Claim
28 words
Method according to claim 4 wherein the amount of the tri-copolymer of formula I added is from 1 to 30 ppm, based on the weight of aqueous system.
Claim 7
Dependent Claim
45 words
Method according to claim 1 wherein the aqueus system is a dilute aqueous dispersion to be treated for imparting dispersant/antifoulant protection, and the amount of the tri-copolymer of formula I added ranges from 1 to 200 ppm, based on the weight of the aqueous system.
Claim 8
Dependent Claim
26 words
Method according to claim 6 wherein the amount of the tri-copolymer added ranges from 2 to 20 ppm, based on the weight of the aqueous system.
Claim 9
Dependent Claim
33 words
Method according to claim 1 wherein the aqueous system is treated to inhibit deposition of scale-forming salts derived from calcium, magnesium, barium or strontium cations and sulphate, carbonate, hydroxide, phosphate and silicate anions.
Claim 10
Dependent Claim
30 words
Method according to claim 1 wherein the tri-copolymer of formula I is used alone or in combination with other compounds known to be useful in the treatment of aqueous systems.
Claim 11
Dependent Claim
43 words
Method according to claim 9 wherein the tri-copolymer of formula I is used together with one or more of polymaleic acid or polyacrylic acid or their copolymers, or substituted copolymers; hydroxyphosphonoacetic acid, hydroxyethyl diphosphonic acid; 2-phosphonobutane-1,2,4-tricarboxylic acid; a triazole; molybdate; and a nitrite.