Utilizing Inorganic Phosphorus Agent Patents (Class 210/697)
  • Patent number: 5045211
    Abstract: There is disclosed a method for the treatment of confined bodies of water such as a swimming pool to remove scale deposits from the surfaces of the vessel containing the water. The water is acidified with a mixture of hydrochloric acid, sulfamic acid and sodium bisulfate to eliminate its total alkalinity, as determined by a standard neutralization test. The water is continuously or repeatedly monitored for total alkalinity following the initial addition of acid, to insure that sufficient acid has been added. The acidified water has a tendency to gain total alkalinity as the scale deposits are removed during the treatment, and monitoring detects this change, permitting correction by addition of acid. After the treatment with the acid, which can last from several hours to several days, any excess treatment acid is neutralized by the addition of a neutralizing agent which is preferably magnesium oxide or magnesium hydroxide.
    Type: Grant
    Filed: March 2, 1990
    Date of Patent: September 3, 1991
    Inventor: Jock Hamilton
  • Patent number: 5032284
    Abstract: A process is provided for controlling the emission of nitrogen dioxide from, and the growth of living organisms in, steam condensate cooling towers and catch basins used in conjunction with steam and condensate of steam derived from ammonia and geothermal brine containing dissolved iron. The process comprises contacting the condensate, in a substantially continuous manner, with a small, substantially less-than-stoichiometric amount of an oxidizing biocide, such as trichloroisocyanuric acid or 1-bromo-3-chloro-5,5-dimethyl-hydantoin, which results in the oxidation of said nitrite formed by activity of bacterial in the condensate to a non-reactive nitrate, and which slows the growth of said bacteria in the cooling tower and catch basin. The process additionally includes periodically introducing into the condensate with amounts of a second biocide, such as dodecylguanidine hydrochloride or isothiazalone, which provides most of the control or organism growth in the cooling tower and catch basin.
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: July 16, 1991
    Assignee: Union Oil Company of California
    Inventors: Darrell L. Gallup, John L. Featherstone
  • Patent number: 5023000
    Abstract: Calcium carbonate scale is controlled by treating calcium carbonate containing waters with a predominantly phosphinate containing composition where has as its major ingredient more than 32 mole percent of a phosphinicosuccinic acid oligomer having the probable structural formula . ##STR1## M is H, Na, K, NH.sub.4, or mixtures thereof; and m and n are either 0 or a small whole number with proviso that either m or n is a small whole number and the sum of m plus n is greater than 2.
    Type: Grant
    Filed: May 10, 1990
    Date of Patent: June 11, 1991
    Assignee: Nalco Chemical Company
    Inventors: James F. Kneller, Barbara E. Fair, Gianfranco F. Mazzani, I. Sergio Di Simone
  • Patent number: 4992208
    Abstract: A method and composition are described for the prevention of the mushing or the disintegration of solid sodium chloride in an aqueous medium.
    Type: Grant
    Filed: April 18, 1989
    Date of Patent: February 12, 1991
    Assignee: Cargill, Incorporated
    Inventor: Donald T. Ireland
  • Patent number: 4966711
    Abstract: Methods for utilizing transition metals as tracers in aqueous liquid systems are provided by this invention. Transition metals with low background levels in system waters are identified as preferred when soluble in said aqueous liquid systems. The transition metals show low levels of deposition on equipment scale and provide reliable information as to the process history of the liquid systems.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: October 30, 1990
    Assignee: Nalco Chemical Company
    Inventors: John E. Hoots, Rodney H. Banks, Donald A. Johnson
  • Patent number: 4952324
    Abstract: A method for treatment of boiler waters is disclosed. The method comprises a synergetic combination of ametacrylic acid-containing polymer with a strongly interacting nonionic surfactant, together with a chelant and/or a phosphate-generating species. The method is particularly effective when the surfactant is an alkoxylated alkylphenol or an alkoxylated alkylphenol ether.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: August 28, 1990
    Assignee: Betz Laboratories, Inc.
    Inventors: Alexander C. McDonald, James L. Soos
  • Patent number: 4941979
    Abstract: A process for stabilizing manganese ions in aqueous solutions is disclosed. The process comprises adding to an aqueous solution containing maganese ions a polymer or copolymer of unsaturated carboxylic compounds such as acrylic acid, methacrylic acid, polyacrylic acid and maleic anhydride and an orthophosphate. The ratio of polymer to orthophosphate is preferrably about 2 to 1.
    Type: Grant
    Filed: February 8, 1989
    Date of Patent: July 17, 1990
    Assignee: Betz Laboratories, Inc.
    Inventor: Stephen M. Kessler
  • Patent number: 4931188
    Abstract: Methods of using novel water soluble polymers to inhibit corrosion and control the formation and deposition of scale imparting compounds in boiler water systems are disclosed. The polymers are comprised of repeat units formed from .gamma., .beta. ethylenically unsaturated compounds, and repeat units formed from allylalkylene ether monomers.
    Type: Grant
    Filed: April 14, 1989
    Date of Patent: June 5, 1990
    Assignee: Betz Laboratories, Inc.
    Inventor: Fu Chen
  • Patent number: 4929425
    Abstract: A method for inhibiting corrosion in industrial cooling waters which contain hardness and a pH of at least 6.5, by dosing the water with a composition which comprises a water-soluble inorganic phosphate capable of inhibiting corrosion in an aqueous alkaline environment and a hydrocarbon polymer containing an N-substituted acrylamide polymers with an amide structure as follows: ##STR1## where R.sub.2 is hydrogen or methyl, where R.sub.1 is a hydrogen or an alkyl and R is alkylene or phenylene, and X is sulfonate, (poly)hydroxyl, (poly)carboxyl or carbonyl, and combinations thereof; or containing derivatized maleic anhydride homo-, co- and terpolymers having N-substituted maleamic acid units, N-substituted maleimide units and maleic acid (and salts) units having a structure as follows: ##STR2## where R.sub.1, R.sub.2 and R.sub.
    Type: Grant
    Filed: February 12, 1988
    Date of Patent: May 29, 1990
    Assignee: Nalco Chemical Company
    Inventors: John E. Hoots, Donald A. Johnson, Dodd W. Fong, James F. Kneller
  • Patent number: 4906384
    Abstract: There is disclosed a method for the treatment of confined bodies of water such as a swimming pool to remove scale deposits from the surfaces of the vessel containing the water. The water is acidified with a mixture of hydrochloric acid, sulfamic acid and sodium bisulfate to eliminate its total alkalinity, as determined by a standard neutralization test. The water is continuously or repeatedly monitored for total alkalinity following the initial addition of acid, to insure that sufficient acid has been added. The acidified water has a tendency to gain total alkalinity as the scale deposits are removed during the treatment, and monitoring detects this change, permitting correction by addition of acid. After the treatment with the acid, which can last from several hours to several days, any excess treatment acid is neutralized by the addition of a neutralizing agent which is preferably magnesium oxide or magnesium hydroxide.
    Type: Grant
    Filed: March 20, 1989
    Date of Patent: March 6, 1990
    Inventor: Jock Hamilton
  • Patent number: 4906383
    Abstract: This invention relates to novel polymeric compositions which are useful for water treatment. These novel compositions are comprised of polymers of .alpha., .beta. ethylenically unsaturated monomer(s), preferably containing carboxylic acid or carboxylic amide functionalities, and amine-containing allyl ether monomers.
    Type: Grant
    Filed: July 5, 1988
    Date of Patent: March 6, 1990
    Assignee: Betz Laboratories, Inc.
    Inventors: Fu Chen, William S. Carey
  • Patent number: 4874526
    Abstract: A process for treating water which comprises adding to the water (a) from 1 to 50 ppm of a phosphonium compound of the formula: ##STR1## in which R represents C.sub.1 -C.sub.6 groups which are unsubstituted or substituted by a cyano, hydroxy, esterified hydroxy or aryl group, R.sub.1 represents a C.sub.8 -C.sub.18 alkyl group and X represents chlorine or bromine, and optionally (b) from 0.1 to 100 ppm of an anionic water treatment agent such as a scale or corrosion inhibiting agent.
    Type: Grant
    Filed: May 26, 1988
    Date of Patent: October 17, 1989
    Assignee: Ciba-Geigy Corporation
    Inventors: Reinhardt Grade, Brien M. Thomas
  • Patent number: 4867944
    Abstract: A method of inhibiting corrosion in cooling tower systems comprising adding to a cooling tower water containing sulfides, hydrocarbons or mixtures thereof as contaminants a corrosion inhibiting composition containing a water-soluble zinc compound, a water-soluble molybdate, a water-soluble orthophosphate and a water-soluble polyphosphate.
    Type: Grant
    Filed: January 13, 1988
    Date of Patent: September 19, 1989
    Assignee: Gulf Coast Performance Chemical, Inc.
    Inventors: Bradley A. Bucher, Jesse H. Jefferies, Harold P. Templet
  • Patent number: 4828713
    Abstract: A method for treatment of boiler waters is disclosed. The method comprises a synergetic combination of a methacrylic acid-containing polymer with a strongly interacting nonionic surfactant, together with a chelant and/or a phosphate-generating species. The method is particularly effective when the surfactant is an alkoxylated alkylphenol or an alkoxylated alkylphenol ether.
    Type: Grant
    Filed: March 15, 1988
    Date of Patent: May 9, 1989
    Assignee: Betz Laboratories, Inc.
    Inventors: Alexander C. McDonald, James L. Soos
  • Patent number: 4820423
    Abstract: A method of preventing corrosion and scale formation on metals exposed to industrial recirculating waters having a pH ranging between about 7.0 to about 9.5, which consists essentially of adding to said industrial recirculating waters an effective amount of a combination of a water-soluble zinc salt, a nitrogen-containing N-alkylated acrylamide zinc complexing polymer and an orthophosphate ion source, wherein:(a) the weight ratio of zinc to nitrogen-containing zinc complexing polymer ranges between 1:1 to about 1:20;(b) the nitrogen-containing N-alkylated acrylamide zinc complexing polymer has a weight average molecular weight ranging between 2,000 to 25,000 and is selected form the group consisting of water-soluble copolymers and terpolymers containing at least two mole percent of an N-alkylated acrylamide monomer, wherein the nitrogen substituted alkyl group contains from 3-12 carbon atoms and wherein the N-alkyl group may be linear or branched.
    Type: Grant
    Filed: September 1, 1987
    Date of Patent: April 11, 1989
    Assignee: Nalco Chemical Company
    Inventors: Guy A. Crucil, Laura J. Blaser
  • Patent number: 4804476
    Abstract: This invention is directed to the use of an improved composition for inhibiting the precipitation of calcium oxalate in aqueous systems. The composition contains: (a) a water soluble phosphate; and (b) a water soluble polycarboxylate having a weight average molecular weight of about 7,000 to about 9,000; wherein the ratio of component (a) to component (b) ranges from 10:1 to 1:10.
    Type: Grant
    Filed: October 23, 1987
    Date of Patent: February 14, 1989
    Assignee: Calgon Corporation
    Inventors: Gloria D. Sinkovitz, Kevin J. Hipolit
  • Patent number: 4797224
    Abstract: Water-soluble zinc:polymer complexes of nitrogen-containing polymers are useful in preventing corrosion in aqueous recirculating systems operating within the pH range of 7.0-9.5, when combined with orthophosphate ion sources.
    Type: Grant
    Filed: September 2, 1987
    Date of Patent: January 10, 1989
    Assignee: Nalco Chemical Company
    Inventors: Guy A. Crucil, Laura J. Blaser
  • Patent number: 4775485
    Abstract: For water-treatment in swimming pools, cooling towers, hot tubs, and other systems, it is desired to feed various chemicals in small quantities but at optimum rates into the system. In several embodiments of the invention the water is recirculated through the system which usually includes a filter. It has been discovered that the chemicals can be fed by enclosing them in generally spherical plastic capsules suggestive of table tennis balls, but about the size of a base ball. The rate of feeding depends upon the size and number of small holes which are provided, or the user pokes through the shell of the capsule, upon the solubility of the chemical, and upon the flow rate of the water through a strainer, skimmer, or other chamber in the system into which the capsule is introduced. The random orientation of the capsule tends to average out variations.
    Type: Grant
    Filed: September 4, 1987
    Date of Patent: October 4, 1988
    Inventor: Kenji Etani
  • Patent number: 4759851
    Abstract: A water soluble polymer composition is disclosed. The polymer has repeat units characterized by the structural formulae: ##STR1## wherein R.sub.1 is H or lower alkyl (C.sub.1 -C.sub.3); R.sub.2 is OH, OM or NH.sub.2 ; M is a water soluble cation; R.sub.3 is a hydroxy substituted alkyl or alkylene radical having from 1 to about 5 carbon atoms or a non-substituted alkyl or alkylene radical having from 1 to 6 carbon atoms; X is an anionic radical; Z is H or hydrogens or a water soluble cation or cations which together counterbalance the valence of X, and a is 0 or 1. The copolymer is effective in inhibiting the precipitation of certain scale forming salts, and also acts to inhibit corrosion of metal parts in contact with water systems.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: July 26, 1988
    Assignee: Betz Laboratories, Inc.
    Inventor: Fu Chen
  • Patent number: 4752443
    Abstract: A method for inhibiting corrosion in industrial cooling waters which contain hardness and a pH of at least 6.5, by dosing the water with a composition which comprises a water-soluble inorganic phosphate capable of inhibiting corrosion in an aqueous alkaline environment and a hydrocarbon polymer containing an N-substituted acrylamide polymers with an amide structure as follows: ##STR1## where R.sub.2 is hydrogen or methyl, R.sub.1 is a hydrogen or an alkyl and R is alkylene or phenylene, and X is sulfonate, (poly)hydroxyl, (poly)carboxyl or carbonyl, and combinations thereof; or containing derivatized maleic anhydride homo-, co- and terpolymers having N-substituted maleamic acid units, N-substituted maleimide units and maleic acid (and salts) units having a structure as follows: ##STR2## where R.sub.1, R.sub.2 and R.sub.
    Type: Grant
    Filed: May 9, 1986
    Date of Patent: June 21, 1988
    Assignee: Nalco Chemical Company
    Inventors: John E. Hoots, Donald A. Johnson, Dodd W. Fong, James F. Kneller
  • Patent number: 4744949
    Abstract: A method for inhibiting corrosion in industrial cooling waters which contain hardness and a pH of at least 6.5, comprising using a water-soluble inorganic phosphate capable of inhibiting corrosion in an aqueous alkaline environment and a co- or terpolymer of acrylic acid and certain substituted acrylamides such as t-butyl acrylamide. A water-soluble organic phosphonate capable of inhibiting corrosion in an alkaline environment may be used as an adjunct for the phosphate.
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: May 17, 1988
    Assignee: Nalco Chemical Company
    Inventors: John E. Hoots, Guy A. Crucil, Ellen L. Johnson
  • Patent number: 4713177
    Abstract: A process for reducing calcium, magnesium and aluminum salt scale build-up in continuous flow or plug flow tube reactors in which a fluid waste undergoes a chemical reaction under heat and pressure to form more environmentally desirable compounds. The process includes the injection of a precipitating reagent into the influent path of a fluid waste stream in a tube reactor to preferentially precipitate calcium, magnesium and aluminum ions which are then carried through and out of the reaction apparatus in a non-scale forming suspension.
    Type: Grant
    Filed: December 19, 1986
    Date of Patent: December 15, 1987
    Assignee: VerTech Treatment Systems, Inc.
    Inventors: Mark T. Atwood, Ronald H. Hall
  • Patent number: 4693829
    Abstract: The present invention is directed to a method to stabilize aluminum ions in recirculating water systems comprising adding to the system 0.1 to 1,000 ppm of a water-soluble polymer having an intrinsic viscosity of 0.05 to 2.5 dl/g in 1.0 M NaCl, prepared from:(A) 35 to 90%, by weight, of an unsaturated carboxylic compound selected from the group consisting of acrylic acid, methacrylic acid, their salts and mixtures thereof; and(B) 10 to 65%, by weight, of an unsaturated sulfonic compound selected from the group consisting of 2-acrylamido-2-methylpropylsulfonic acid, 2-methacrylamido-2-methylpropylsulfonic acid, their salts and mixtures thereof.
    Type: Grant
    Filed: April 3, 1986
    Date of Patent: September 15, 1987
    Assignee: Calgon Corporation
    Inventor: Bennett P. Boffardi
  • Patent number: 4680124
    Abstract: Small amounts of certain water-soluble phosphorous compounds prevent calcium polyacrylate scale.
    Type: Grant
    Filed: January 8, 1987
    Date of Patent: July 14, 1987
    Assignee: Nalco Chemical Company
    Inventors: Paul R. Young, Mary E. Koutek, John A. Kelly
  • Patent number: 4680125
    Abstract: A composition for inhibiting deposition of scale in aqueous systems is disclosed which comprises carboxymethylcellulose and gluconic acid or glucoheptonic acid or both, or their water soluble salts. The composition is incorporated in the aqueous system in concentrations sufficient to substantially completely prevent scale deposition.
    Type: Grant
    Filed: June 6, 1986
    Date of Patent: July 14, 1987
    Assignee: W. R. Grace & Co.
    Inventors: Dionisio G. Cuisia, Chih M. Hwa
  • Patent number: 4671934
    Abstract: A method of controlling the corrosion of a metal surface in contact with an aqueous system while at the same time preventing the precipitation of potentially scale-forming calcium phosphate. The water in such systems is treated with a combination of a source of orthophosphate ion and a mixture of methylene phosphonic acid derivatives of C.sub.6 diamines, or the salts thereof. A composition for preventing the precipitation of calcium phosphate containing a mixture of methylene phosphonic acid derivatives of C.sub.6 diamines or the salts thereof.
    Type: Grant
    Filed: April 18, 1986
    Date of Patent: June 9, 1987
    Assignee: Buckman Laboratories, Inc.
    Inventors: John P. Terry, Oscar W. May
  • Patent number: 4659481
    Abstract: A water soluble polymer composition is disclosed. The polymer has repeat units characterized by the structural formulae: ##STR1## wherein R.sub.1 is H or lower alkyl (C.sub.1 -C.sub.3); R.sub.2 is OH, OM, or NH.sub.2 ; M is a water soluble cation; R.sub.3 is a hydroxy substituted alkyl or alkylene radical having from 1 to 6 carbon atoms or a non-substituted alkyl or alkylene radical having from 1 to 6 carbon atoms; X is an anionic radical; Z is H or hydrogens or a water soluble cation or cations which together counterbalance the valence of X, and a is 0 or 1. The copolymer is effective in inhibiting the precipitation of certain scale forming salts, and also acts to inhibit corrosion of metal parts in contact with water systems.
    Type: Grant
    Filed: May 16, 1986
    Date of Patent: April 21, 1987
    Assignee: Betz Laboratories Inc.
    Inventor: Fu Chen
  • Patent number: 4659480
    Abstract: Scale control polymers and methods of use are disclosed. The polymers are water soluble and are composed of repeat units formed from an .alpha., .beta.ethylenically unsaturated commpound, and repeat units formed from allyl alkylene phosphite ethers.
    Type: Grant
    Filed: January 3, 1986
    Date of Patent: April 21, 1987
    Assignee: Betz Laboratories, Inc.
    Inventors: Fu Chen, Keith A. Bair
  • Patent number: 4640793
    Abstract: The instant invention is directed to an admixture, and its use in inhibiting scale and corrosion in aqueous systems, comprising:(a) a water-soluble polymer having a weight average molecular weight of less than 25,000, as determined by low angle laser light scattering, comprising an unsaturated carboxylic acid and an unsaturated sulfonic acid, or their salts, having a ratio of 1:20 to 20:1, and(b) at least one compound selected from the group consisting of water-soluble polycarboxylates, phosphonates, phosphates, polyphosphates, metal salts and sulfonates.The instant invention is also directed to a method of inhibiting the formation of insoluble alluvial, metal oxide and metal hydroxide deposits in an aqueous system, comprising adding to the system at least 0.
    Type: Grant
    Filed: May 9, 1985
    Date of Patent: February 3, 1987
    Assignee: Calgon Corporation
    Inventors: Leonard J. Persinski, Jerry L. Walker, Bennett P. Boffardi
  • Patent number: 4634532
    Abstract: The instant invention is directed to a process for the control of scale formation and deposition in thermal or reverse osmosis membrane desalination plants, comprising adding to the water 0.1 to 100 ppm of (a) a water soluble orthophosphate and (b) at least one compound selected from the group consisting of water soluble polycarboxylates, phosphonates, phosphates, sulfonates and polyamides.
    Type: Grant
    Filed: September 25, 1985
    Date of Patent: January 6, 1987
    Assignee: Calgon Corporation
    Inventors: Douglas P. Logan, Thomas E. Cornelius, III, Susan P. Rey
  • Patent number: 4631131
    Abstract: The accumulation of scale in an aqueous system is inhibited by the addition of a copolymer of maleic acid or anhydride or fumaric acid and allyl sulfonic acid and a water soluble organic phosphonic acid such as aminotri(methylene phosphonic acid), ethylenediaminetetra(methylene phosphonic acid), hydroxyethylidene diphosphonic acid and 2-phosphonobutane tricarboxylic acid-1,2,4 or water soluble salts thereof. Scale can actually be removed by the addition of these materials to pressurized boiler water systems. Allyl or vinyl copolymers, a phosphonate, and optionally a water soluble, hardness precipitating agent such as a carbonate or a phosphate may be used when treating pressurized boilers to provide an in-service cleaning effect.
    Type: Grant
    Filed: September 10, 1985
    Date of Patent: December 23, 1986
    Assignee: R. W. Grace & Co.
    Inventors: Dionisio G. Cuisia, Chih M. Hwa
  • Patent number: 4584104
    Abstract: A method of inhibiting amorphous silica scale formation on surfaces in contact with industrial waters containing dissolved silicates is disclosed. The method involves treating the industrial waters with a boron compound which dissolves in or hydrolyzes in these industrial waters to give the orthoborate ion. The preferred boron compound is boric acid, its salts, or precursors.
    Type: Grant
    Filed: June 29, 1984
    Date of Patent: April 22, 1986
    Assignee: Nalco Chemical Company
    Inventor: Leonard Dubin
  • Patent number: 4575425
    Abstract: The instant invention is directed to a composition useful for inhibiting precipitation of calcium oxalate in aqueous systems comprising: (a) a water soluble phosphate, phosphonate or phosphinate; and (b) a water soluble polyelectrolyte wherein the ratio of component (a) to component (b) ranges from 10:1 to 1:10.The instant invention is further directed to a method of inhibiting the precipitation and deposition of calcium oxalate scale in an aqueous system, comprising adding to said system an effective amount of the above described composition, wherein said aqueous system has a pH greater than or equal to 2.0.
    Type: Grant
    Filed: December 24, 1984
    Date of Patent: March 11, 1986
    Assignee: Calgon Corporation
    Inventors: Bennett P. Boffardi, John P. Farkas, Monica A. Yorke
  • Patent number: 4561981
    Abstract: A method for controlling, preventing, or removing fouling deposits comprising microencapsulating fouling control chemicals in a slow release capsule. The microcapsules are applied to the substrate to be treated, where they stick to the substrate and slowly release the active treating agents.
    Type: Grant
    Filed: January 27, 1984
    Date of Patent: December 31, 1985
    Inventor: William G. Characklis
  • Patent number: 4560481
    Abstract: A method of inhibiting corrosion and controlling deposition in aqueous mediums, such as in cooling water systems, wherein iron containing well water is used as a water make-up source, is disclosed. The method comprises addition of certain water soluble acrylic acid type/allyl hydroxy propyl sulfonate ether copolymers to the desired aqueous medium.
    Type: Grant
    Filed: December 13, 1984
    Date of Patent: December 24, 1985
    Assignee: Betz Laboratories, Inc.
    Inventor: Orin Hollander
  • Patent number: 4552665
    Abstract: The instant invention is directed to a process for inhibiting the precipitation of dissolved manganese ion and its reaction products in aqueous solutions, comprising adding to the aqueous solution 0.1 to 20 ppm of a copolymer of an unsaturated carboxylic acid or salt selected from the group consisting of acrylic acid and methacrylic acid and an unsaturated sulphonic acid or salt selected from the group consisting of 2-acrylamido-2-methylpropylsulphonic acid and 2-methacrylamido-2-methylpropylsulphonic acid.
    Type: Grant
    Filed: May 4, 1984
    Date of Patent: November 12, 1985
    Assignee: Calgon Corporation
    Inventors: Paul H. Ralston, Sandra L. Whitney
  • Patent number: 4548787
    Abstract: Compositions for inhibiting mineral scale and the corrosion of metals particularly the cavitation corrosion of aluminum in the presence of aqueous liquids are disclosed. The combination of a water-soluble phosphate with at least one of a water-soluble molybdate, tungstate, or selenate is disclosed as providing a synergistic protective effect against the cavitation corrosion of aluminum in aqueous liquids.
    Type: Grant
    Filed: February 9, 1983
    Date of Patent: October 22, 1985
    Assignee: BASF Wyandotte Corporation
    Inventors: Joe C. Wilson, Stanley T. Hirozawa, John J. Conville
  • Patent number: 4547294
    Abstract: Formation of alkaline scale on cooling tower and associated heat transfer surfaces contacted by circulating water is reduced or substantially eliminated while minimizing equipment corrosion by introducing an effective amount of carbon dioxide and a threshold effect chemical scale control additive to the circulating water.
    Type: Grant
    Filed: January 19, 1984
    Date of Patent: October 15, 1985
    Assignee: Mechanical Equipment Company, Inc.
    Inventor: Richard W. Goeldner
  • Patent number: 4534866
    Abstract: A water system deposit control method and composition of high calcium tolerance are herein disclosed. The composition comprises a reaction product formed from acrylic acid, hydroxylated lower alkyl acrylate and hypophosphorous acid. In accordance with the method herein, an effective amount, from about 0.1-500 ppm of the composition is added to the water system, e.g., cooling water system, so as to inhibit the build-up or agglomeration of undesirable deposits along the metal surfaces on contact with the water.
    Type: Grant
    Filed: February 17, 1983
    Date of Patent: August 13, 1985
    Assignee: Betz Laboratories, Inc.
    Inventor: Larry W. Becker
  • Patent number: 4502978
    Abstract: A method of enhancing corrosion inhibition of inorganic corrosion inhibitors, particularly stabilized phosphate corrosion inhibitors, when used in high hardness waters containing at least 800 ppm total hardness which comprises adding to the high hardness waters a combined product which includes both the inorganic corrosion inhibitor system and an effective amount of a water-soluble acrylic acid:acrylamide copolymer having an acrylic acid:acrylamide weight ratio between 1:4 and 1:2 and having a molecular weight between 1,000-25,000.
    Type: Grant
    Filed: November 8, 1982
    Date of Patent: March 5, 1985
    Assignee: Nalco Chemical Company
    Inventors: John A. Romberger, Daniel A. Meier
  • Patent number: 4452713
    Abstract: Method, composition and article of manufacture to inhibit the staining of water-contacting surfaces, such as those in a toilet bowl, which is caused by manganese present in household water in the presence of an oxidizing material. Manganese staining is inhibited by supplying to the water 0.05 ppm to 10 ppm of a glassy phosphate having the formula MO(MPO.sub.3).sub.n M wherein M is sodium or potassium and n is an integer of from about 6 to about 21.
    Type: Grant
    Filed: November 1, 1982
    Date of Patent: June 5, 1984
    Assignee: The Procter & Gamble Company
    Inventor: Leonard E. Small
  • Patent number: 4446028
    Abstract: A water soluble isopropenylphosphonic acid copolymer composition and method of use thereof are disclosed. The copolymer comprises repeat units (a) of the formula ##STR1## wherein X=OH or OM, wherein M is a cation; and repeat units (b) of the formula ##STR2## wherein R.sub.1 is chosen from the group consisting of hydroxy, hydroxylated alkoxy, and amide and water soluble salts thereof; R.sub.2 is H, or lower alkyl of from 1-3 carbon atoms. These copolymers are effective in inhibiting the precipitation of certain scale forming salts, and also act to inhibit corrosion in water systems.
    Type: Grant
    Filed: December 20, 1982
    Date of Patent: May 1, 1984
    Assignee: Betz Laboratories, Inc.
    Inventor: Larry W. Becker
  • Patent number: 4444675
    Abstract: Formation of alkaline scale in water distillation equipment is reduced or substantially eliminated without a significant increase in equipment corrosion rate by dissolving an effective amount of carbon dioxide in brine which is boiling or flashed or which has been boiled or flashed and which contains an effective amount of a high temperature threshold effect chemical scale control additive.
    Type: Grant
    Filed: February 18, 1982
    Date of Patent: April 24, 1984
    Assignee: Mechanical Equipment Company, Inc.
    Inventor: Richard W. Goeldner
  • Patent number: 4443340
    Abstract: A method for inhibiting corrosion and controlling deposition in an iron containing aqueous medium is disclosed. The method is capable of providing for the formation of a protective passive oxide film on the metallic surfaces in contact with the aqueous medium without resulting in unacceptable iron based deposition or fouling. Surprisingly, the method does not call for the addition of an organic-phosphonic acid compound or derivative to the aqueous medium as would be normally expected due to the known iron dispersing characteristics of these type compounds. The invention comprises maintaining the pH level at 5.5 or above, assuring that a certain minimal calcium or other ion level is maintained, and adding to the system an orthophosphate compound, a water soluble acrylic acid/hydroxyalkylacrylate copolymer, and a topping agent selected from the group consisting of effective water soluble aminocarboxylic acids, lignosulfonates, citric acid, and tannic acid, and water soluble salt forms and mixtures thereof.
    Type: Grant
    Filed: May 24, 1983
    Date of Patent: April 17, 1984
    Assignee: Betz Laboratories, Inc.
    Inventors: Roger C. May, Frank C. Sessa
  • Patent number: 4442009
    Abstract: The present invention is directed to a method for controlling scale which would otherwise be formed from water-soluble calcium, magnesium and iron impurities contained in boiler water which would provide calcium, magnesium and iron ions.
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: April 10, 1984
    Assignee: Betz Entec, Inc.
    Inventors: Richard P. O'Leary, David W. Reichgott
  • Patent number: 4440792
    Abstract: The "livering" or gelling of corn steep liquor or liquid products containing corn steep liquor is prevented or reversed by the addition of an effective amount of a calcium complexing agent, preferably at a pH of less than about 3.8.
    Type: Grant
    Filed: September 7, 1982
    Date of Patent: April 3, 1984
    Assignee: A. E. Staley Manufacturing Company
    Inventors: Marion M. Bradford, Frank T. Orthoefer, Kenneth N. Wright
  • Patent number: 4440721
    Abstract: Compositions for inhibiting mineral scale and the corrosion of metals particularly the cavitation corrosion of aluminum in the presence of aqueous liquids are disclosed. The combination of a water-soluble phosphate with at least one of a water-soluble molybdate, tungstate, or selenate is disclosed as providing a synergistic protective effect against the cavitation corrosion of aluminum in aqueous liquids.
    Type: Grant
    Filed: February 11, 1983
    Date of Patent: April 3, 1984
    Assignee: BASF Wyandotte Corporation
    Inventors: Joe C. Wilson, Stanley T. Hirozawa, John J. Conville
  • Patent number: 4436628
    Abstract: The instant invention is directed to a process for the inhibition of scale and corrosion formation in an aqueous system, comprising adding to the system about 0.1 to 100 ppm, by weight based on the total aqueous content of said system, of 103 to 115% polyphosphoric acid, or neutral salts thereof.
    Type: Grant
    Filed: September 20, 1982
    Date of Patent: March 13, 1984
    Assignee: Calgon Corporation
    Inventors: Paul H. Ralston, Sandra L. Whitney
  • Patent number: 4401587
    Abstract: A method of inhibiting corrosion of low carbon steel in an aqueous system comprising treating said system with 1.0 to 300 parts per million by weight of the total aqueous content of said system, of a composition comprising aminomethylphosphonic acid compounds and polymaleic anhydride or amine adducts thereof in a weight ratio of from 10:1 to 1:10.
    Type: Grant
    Filed: December 16, 1981
    Date of Patent: August 30, 1983
    Assignee: Calgon Corporation
    Inventor: Bennett P. Boffardi
  • Patent number: 4388194
    Abstract: A method of preventing sludge deposition in the treatment of geothermal steam condensate with iron catalyzed/hydrogen peroxide by carrying out the treatment in the presence of an inorganic polyphosphate.
    Type: Grant
    Filed: September 4, 1981
    Date of Patent: June 14, 1983
    Assignee: FMC Corporation
    Inventor: William A. Hills