摘要:
Polyether polyamino methylene phosphonates, when added to various industrial water systems in concentrations between 0.1 mg/L and 50 mg/L, stabilize soluble zinc, manganese and iron ions and their reaction products, in desirable forms and reduced particle sizes. In particular, this stabilization can be achieved under severe conditions which include elevated pH, high dissolved solids content, and high saturation levels of calcium carbonate.
摘要:
An anionic/cationic polymer mixture comprising:(a) a polyanion selected from polyacrylic acid, polymethacrylic acid, and polymaleic anhydride, each optionally copolymerized with each other, or optionally copolymerized with acrylamide up to a molar unit ratio of 1:1, provided that the total polyanionic weight average molecular weight is from about 1 to 5 thousand, and(b) the polycation poly(dimethyldiallylammonium chloride) having a weight average molecular weight of from about 25 thousand to 1 million,wherein the weight ratio of polyanion (a) to polycation (b) is from 1:2 to 1:8, has been found to give excellent inhibition of the formation, deposition and adherence of various alkali metal and alkaline earth metal scales, e.g., sodium sulfate, sodium carbonate, and calcium carbonate scales in the stringent conditions which characterize black liquor heaters, evaporators, etc. in paper mills, particularly in association with Kamyr and similar wood chip digesters, characterized by elevated pH's of 12 and higher, high dissolved organic and inorganic solids concentrations, and elevated temperatures and pressures.
摘要:
A method for controlling the formation of silica/silicate deposits in aqueous systems by adding an effective amount, preferably at least 0.1 ppm, of 2-phosphonobutane tricarboxylic acid-1,2,4 and, optionally, an anionic polymer, preferably a carboxylic/sulfonic polymer, or salts thereof to the aqueous system being treated. Borate or molybdate ion sources may also be added.
摘要:
Compositions and methods of using such compositions for reducing copper ion discharge from aqueous systems is disclosed and claimed. The composition includes a synergistic combination of at least two different benzotriazoles or salts thereof that effectively provides an erosion-resistant barrier on copper-containing surfaces of industrial systems.
摘要:
On-Line and Off-Line methods of simultaneously cleaning and disinfecting an industrial water system are described and claimed. The methods involve the addition to the water of the industrial water system of a Compound selected from the group consisting of the alkali salts of chlorite and chlorate and mixtures thereof; and an acid, followed by allowing the water in the industrial water system to circulate for several hours. The reaction of the alkali salts of chlorite and chlorate and acid produces chlorine dioxide in-situ in the water of the industrial water system. The chlorine dioxide kills microorganisms and the acid acts to remove deposits upon the water-contact surfaces of the equipment. An alternative method involves the use of a chelating agent and a biocide. Other possible cleaning and disinfection reagents may be added as needed including corrosion inhibitors, chelating agents, biocides, surfactants and reducing agents. These cleaning and disinfecting methods work in a variety of industrial water systems including cooling water and boiler water systems.
摘要:
A method of use of a composition including either or both isomers of hydrogenated methylbenzotriazole, namely, 5-Methyl-1H-Benzotriazole or 4-Methyl-1H-Benzotriazole which have been at least about 50% hydrogenated, to form corrosion inhibiting films on metal surfaces in an aqueous environment. The hydrogenated methylbenzotriazole compositions provide both improved passivation and improved film persistence when charged to aqueous industrial systems either on a continuous or on an intermittent basis. Continuous dosing is generally kept at a constant >0.5, typically 1-2 ppm in the aqueous system to be treated; intermittent doses are generally 10-20 ppm once every week or two or more. Beyond the improved characteristics described above, films formed from the inventive composition also reduce spiking in corrosion rates immediately following halogen addition; foster faster return to pre-halogenation corrosion rates post-halogenation; and reduce the rate of conversion of phosphonate to orthophosphate, which reduces scale potential. For these reasons, the present compositions are either continuously or intermittently fed and effective to inhibit corrosion of copper and copper alloy surfaces subjected to alkaline, neutral or slightly acidic aqueous systems.
摘要:
An aqueous system containing scale forming salts including both calcium carbonate and calcium phosphate and characterized by high pH and high calcite concentrations which further contains a synergistic effective amount of a combination comprising (A) a polyether polyamino methylene phosphonate, (B) a terpolymer comprising the monomers of acrylic acid, sulfophenoxymethallyl ether and maleic acid, (C) a hydroxyphosphonoacetic acid, and (D) a phosphonocarboxylic acid copolymer comprising the monomers of acrylic acid, telomer with (1-hydroxy-1-methylethyl) phosphinic acid monosodium salt, and 2-acrylamido 2 methylpropane sulfonic acid, is disclosed. A method for inhibiting the formation, deposition and adherence of such scale forming salts in the aqueous system employing the synergistic combination is also provided.
摘要:
An aqueous system containing scale forming salts including both calcium carbonate and calcium phosphate and characterized by high pH and high calcite concentrations which further contains a synergistic effective amount of a combination comprising (A) a polyether polyamino methylene phosphonate, (B) a terpolymer comprising the monomers of acrylic acid, sulfophenomethallyl ether and maleic acid, and (C) a hydroxyphosphonoacetic acid, is disclosed. A method for inhibiting the formation, deposition and adherence of such scale forming salts in the aqueous system employing the synergistic combination is also provided.
摘要:
An aqueous system containing scale forming salts including both calcium carbonate and calcium phosphate and characterized by high pH and high calcite concentrations which further contains a synergistic effective amount of a combination comprising (A) a polyether polyamino methylene phosphonate, (B) a terpolymer comprising the monomers of acrylic acid, sulfophenomethallyl ether and maleic acid, and (C) a hydroxyphosphonoacetic acid, is disclosed. A method for inhibiting the formation, deposition and adherence of such scale forming salts in the aqueous system employing the synergistic combination is also provided.
摘要:
An aqueous system containing scale forming salts including both calcium carbonate and calcium phosphate and characterized by high pH and high calcite concentrations which further contains a synergistic effective amount of a combination comprising (A) a polyether polyamino methylene phosphonate, and (B) a terpolymer comprising the monomers of acrylic acid, sulfophenomethallyl ether and maleic acid, is disclosed. A method for inhibiting the formation, deposition and adherence of such scale forming salts in the aqueous system employing the synergistic combination is also provided.