Nitrogen Containing Patents (Class 210/700)
  • Patent number: 6391207
    Abstract: A method for reducing or preventing the formation of scale in a municipal or industrial waste water treatment facility comprising introducing an antiscalent composition which comprises: A) A water soluble polymer of molecular weight below 20,000 and containing anionic groups, and B) A sequesterant compound, selected from the group consisting of phosphonates, phosphates, metaphosphates and orthophosphates including derivatives and salts thereof. Preferred antiscalent compositions include a blend of A) a polymer of acrylic acid and/or maleic acid and B) diethylentriamine penta (methylenephosphonic acid) or salts thereof. The invention is of particular value for the treatment of struvite scale in sewage treatment works.
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: May 21, 2002
    Assignee: Ciba Specialty Chemicals Water Treatments Ltd.
    Inventor: Jean Achille Emile Robert Cluyse
  • Patent number: 6337047
    Abstract: This invention relates to a process for dispersing corrosion products, specifically iron oxide, in steam generating boilers. Improved dispersion is achieved by adding a dispersant to a feedpoint of the steam generating boiler where the composition comprises: (a) a copolymer of sulfonated styrene and maleic anhydride or maleic acid; and (b) diethylenetriamine penta (methylene phosphonic acid).
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: January 8, 2002
    Assignee: Ashland Inc.
    Inventors: Kostan B. Charkhutian, Bruce L. Libutti, Kaj D. Rondum
  • Patent number: 6264839
    Abstract: Phosphonomethylated poly-vinylamines which contain as characteristic structural elements units of the formula where R1 is hydrogen, C1-C6-alkyl or and X is hydrogen, an alkali metal, ammonium or one equivalent of an alkaline earth metal, are obtainable by phosphonomethylation of polymers which contain N-vinyl-amide or vinylamine groups and are useful as detergent additives and water treatment agents.
    Type: Grant
    Filed: July 12, 1993
    Date of Patent: July 24, 2001
    Assignee: BASF Aktiengesellschaft
    Inventors: Juergen Mohr, Knut Oppenlaender, Walter Denzinger, Heinrich Hartmann, Richard Baur, Charalampos Gousetis, Alexander Kud
  • Patent number: 6207079
    Abstract: This invention relates to a scale inhibiting composition for aqueous systems comprising (a) polyaspartic acid, and (b) a water soluble phosphonated oligomer. The compositions are effective scale and/or corrosion inhibitors, but are also advantageous from an environmental standpoint because they are non-toxic, contain no heavy metals, and have little or no phosphorus. They also have sufficient calcium/hardness tolerance, are chlorine/bromine stable, and are effective corrosion inhibitors.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: March 27, 2001
    Assignee: Ashland Inc.
    Inventors: Pavol Kmec, Dwight E. Emerich
  • Patent number: 6187195
    Abstract: The invention relates to the use of polyaspartic acids and their mixtures with surfactants and emulsifiers for inhibiting or delaying deposit formation by sparingly soluble organic and inorganic components in the feed of a process that uses a membrane.
    Type: Grant
    Filed: May 10, 1999
    Date of Patent: February 13, 2001
    Assignee: Bayer AG
    Inventors: Wolfgang Zarges, Torsten Groth, Winfried Joentgen, Andreas Gröschl
  • Patent number: 6177047
    Abstract: The invention herein relates to water-treatment technology, namely compositions comprising a phosphonic acid, a zinc salt and a metal salt. A preferred metal salt is aluminum tri-chloride whereas amino tris methylene phosphonic acid is a preferred phosphonic species. The use of the compositions in water-treatment methods is also described.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: January 23, 2001
    Inventors: Krzysztof Kuczynski, Michel Alex Omer Ledent
  • Patent number: 6083403
    Abstract: This invention relates to novel organic phosphonate compounds which can be used as water treatment agents. More specifically, this invention relates to 1,1 -diphosphonic acid N-oxides and water-soluble salts thereof for control of corrosion and scale in aqueous systems. Preferred N-oxides are morpholinomethane-1,1-diphosphonic acid N-oxide and N,N-dimethylaminomethane-1,1-diphosphonic acid N-oxide.
    Type: Grant
    Filed: November 5, 1998
    Date of Patent: July 4, 2000
    Assignee: Nalco Chemical Company
    Inventors: Jiansheng Tang, Michael A. Kamrath
  • Patent number: 6077440
    Abstract: A method of controlling the deposition of silica-containing scales and their adhesion to surfaces in contact with an aqueous system is disclosed which comprises adding to the aqueous system a synergistic combination of:(a) diethylenetriamine penta methylene phosphonic acid; and(b) a material selected from the group consisting of 2 phosphonobutane-1,2,4-tricarboxylic acid; high molecular weight, 3:1, acrylic acid/allylhydroxypropylsulfonate ether copolymer; ethylene oxide-propylene oxide block copolymers; and polyepoxysuccinic acid and salts thereof.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: June 20, 2000
    Assignee: BetzDearborn Inc.
    Inventors: Donald C. Roe, Bradley J. Utzka
  • Patent number: 6066260
    Abstract: In the present state of art, use is made of aqueous mixtures of sodium phosphates, preferably mixtures of pentasodium triphosphate (for softening) and sodium dihydrogen phosphate (to reduce the pH) of hard and slightly alkaline water in aquaria to values acceptable especially for ornamental tropical fish. This inherently effective preparation for softening and acidifying the aquarium water leads, however, to the clouding of the water after a short time and to chalk flocculation, while the hydrolysis of the triphosphate results in an increased level of orthophosphate which is particularly favorable to the growth of algae. The invention prevents these drawbacks by the use of phosphonic acid compounds which complex the alkaline earth metal ions determining the hardness of water. Preferred phosphonic acids here are ethylene diamine tetra(methylene phosphonic acid) and its pentasodium salt and diethylene triamine penta(methylene phosphonic acid) and its heptasodium salt.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: May 23, 2000
    Assignee: Amtra Aquaristik GmbH
    Inventor: Markus Biffar
  • Patent number: 6036740
    Abstract: Concentrated aqueous gypsum slurries containing small amounts of water soluble phosphonates are non-clogging when used in drip irrigation systems.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: March 14, 2000
    Inventors: John C. Miller, Deborah L. Miller
  • Patent number: 5866032
    Abstract: A composition for of controlling scale formation and deposition and corrosion in aqueous systems is described wherein a treatment solution of a substoichiometric amount of a composition comprising a scale/corrosion inhibitor in combination with a substituted alkylpolycarboxylate is employed. The scale/corrosion inhibitor can be a phosphonate such as hydroxyethylidene diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, hydroxyphosphonoacetic acids, amino phosphonates; terpolymers, copolymers and homopolymers of acrylic acid, maleic acid, epoxysuccinic acids such as polyepoxysuccinic acid or mixtures thereof. The substituted alkylpolycarboxylates are compounds of the general structure: R--X.sub.m --Y.sub.n wherein R is a hydrocarbon functionality having 4 to 18 carbons; X, when present, is --NH--, --NY.sup.1 --, --N-->O, --N--OC--Y.sup.1, --O-- or --S--; n is greater than or equal to 1; m=O or 1; and Y and Y.sup.
    Type: Grant
    Filed: November 18, 1997
    Date of Patent: February 2, 1999
    Assignee: BetzDearborn Inc.
    Inventors: William S. Carey, Libardo A. Perez, Donald T. Freese, Judith L. Barron
  • Patent number: 5858244
    Abstract: A biodegradable scale inhibitor and dispersant is provided. The scale inhibitor includes a copolymer comprising at least one of N-oxygenatedhydrocarbonamide monomers and at least one of amino acid monomers. A method of reducing scale build-up on heating exchanger surfaces that come in contact with an industrial water is provided by adding a copolymer comprising at least one of N-oxygenatedhydrocarbonamide monomers and at least one of amino acid monomers to the water system such as cooling towers.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: January 12, 1999
    Assignee: Nalco Chemical Company
    Inventors: Jiansheng Tang, Ronald V. Davis
  • Patent number: 5788857
    Abstract: This invention relates to the use of iminoalkylenephosphonic acids to prevent corrosion, including both localized corrosion and general corrosion on iron based metal surfaces in contact with a corrosive system water in an aqueous system. The invention also relates to the use of the iminoalkylenephosphonic acids to control formation, deposition and adherence of scale at the surfaces of metals in contact with a scale-forming system water in an aqueous system.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: August 4, 1998
    Assignee: Nalco Chemical Company
    Inventors: Bo Yang, Jiansheng Tang
  • Patent number: 5783524
    Abstract: Glycine-N,N-diacetic acid derivatives and their alkali metal, akaline earth metal, ammonium and substituted ammonium salts, used as completing agents for alkaline earth metal and heavy metal ions in the production and transport of petroleum and natural gas.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: July 21, 1998
    Assignee: BASF Aktiengesellschaft
    Inventors: Thomas Greindl, Wilhelmus Slotman
  • Patent number: 5776875
    Abstract: A biodegradable scale inhibitor and dispersant is provided. The scale inhibitor includes a copolymer comprising at least one of N-oxygenatedhydrocarbonamide monomers and at least one of amino acid monomers. A method of reducing scale build-up on heating exchanger surfaces that come in contact with an industrial water is provided by adding a copolymer comprising at least one of N-oxygenatedhydrocarbonamide monomers and at least one of amino acid monomers to the water system such as cooling towers.
    Type: Grant
    Filed: July 16, 1996
    Date of Patent: July 7, 1998
    Assignee: Nalco Chemical Company
    Inventors: Jiansheng Tang, Ronald V. Davis
  • Patent number: 5772893
    Abstract: The invention is a method for the prevention of scale formation on metal or other surfaces in contact with scale-forming industrial water with an effective scale-inhibiting amount of an ether 1,1-diphosphonate of the general formula: ##STR1## The invention is also a method for the prevention of corrosion on metal surfaces in contact with corrosive industrial water with an effective corrosion-inhibiting amount of an ether 1,1-diphosphonate of the same general formula. A preferred ether 1, 1-diphosphonate is 1,1, diphosphono-4,7-dioxaoctane for both methods.
    Type: Grant
    Filed: August 13, 1996
    Date of Patent: June 30, 1998
    Assignee: NALCO Chemical Company
    Inventors: Peter E. Reed, Michael A. Kamrath, Phillip W. Carter, Ronald V. Davis
  • Patent number: 5772913
    Abstract: 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.
    Type: Grant
    Filed: September 24, 1996
    Date of Patent: June 30, 1998
    Assignee: Calgon Corporation
    Inventors: Jasbir S. Gill, Jennifer R. Parsons
  • Patent number: 5709814
    Abstract: 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.
    Type: Grant
    Filed: October 6, 1995
    Date of Patent: January 20, 1998
    Assignee: Calgon Corporation
    Inventor: Jasbir S. Gill
  • Patent number: 5707529
    Abstract: A method for inhibiting the formation, deposition and adherence of scale forming salts including calcium carbonate and calcium phosphate in an aqueous system having a pH of at least 8.5 and a calcite saturation level of at least 100 times the solubility limit of calcium as calcite, including adding to the aqueous system 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.
    Type: Grant
    Filed: September 24, 1996
    Date of Patent: January 13, 1998
    Assignee: Calgon Corporation
    Inventors: Jasbir S. Gill, Jennifer R. Parsons
  • Patent number: 5702634
    Abstract: 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.
    Type: Grant
    Filed: October 6, 1995
    Date of Patent: December 30, 1997
    Assignee: Calgon Corporation
    Inventor: Jasbir S. Gill
  • Patent number: 5681479
    Abstract: Phosphonic coletomers of the formula I: ##STR1## wherein X.sub.5 is hydrogen, an alkali metal atom, an alkaline earth metal atom, or an ammonium or amine residue; and A.sub.2 is a copolymer residue comprising two different residues ##STR2## wherein r is an integer ranging from 2 to 100, and wherein, in the first residue, W.sub.3 is --COOH, and in the second residue, W.sub.3 is --CONHC(CH.sub.3).sub.2 CH.sub.2 SO.sub.3 X.sub.5 wherein X.sub.5 is as hereinbefore defined. The cotelomers inhibit scale and corrosion in aqueous systems.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 28, 1997
    Assignee: FMC Corporation (UK ) Limited
    Inventors: Elizabeth A. Kerr, Jan Rideout
  • Patent number: 5647995
    Abstract: An improved method is disclosed for the preparation of novel alkali metal diphosphinate salts by the reaction of an acetylenic compound with an alkali metal hypophosphite in the presence of a free radical source, the use of these novel compounds in further reactions to prepare diphosphonate compounds and diphosphinate containing adducts, oligomers and polymers and utilization of these compounds, polymers and oligomers to control calcium carbonate scale and mild steel corrosion in cooling water.
    Type: Grant
    Filed: April 29, 1994
    Date of Patent: July 15, 1997
    Assignee: Nalco Chemical Company
    Inventors: James F. Kneller, Donald A. Johnson, Vytas Narutis, Binaifer S. Khambatta
  • Patent number: 5645756
    Abstract: The tendency of aqueous solutions of urea and other NH-containing compositions to force instability of hardness factors has been found to be detrimental to processes and apparatus employing them. The reliability of these processes and apparatus is improved by the inclusion of hardness-suppressing compositions, which preferably include both a water-soluble polymer and a phosphonate. In particular, agricultural and NO.sub.x -reducing applications are improved, especially for solutions containing urea hydrolysis products and the salts of them.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: July 8, 1997
    Assignee: Nalco Fuel Tech
    Inventors: Leonard Dubin, W. Robert Epperly, Barry Normand Sprague, Thure von Harpe
  • Patent number: 5643462
    Abstract: Tannin containing polymers, their method of production and methods of using as water treatment agents are disclosed. The tannin containing polymers comprise copolymers of tannin and a cationic monomer. Another embodiment comprises tannin containing polymers of tannin, cationic monomer and at least one monomer selected from the group consisting of an anionic monomer and a nonionic monomer.
    Type: Grant
    Filed: May 20, 1994
    Date of Patent: July 1, 1997
    Assignee: BetzDearborn Inc.
    Inventors: Jen-Chi Chen, Fu Chen, Gerald C. Walterick, Jr., Stephen R. Vasconcellos
  • Patent number: 5629385
    Abstract: This invention is directed to certain novel N-functionalized polyallylamines having recurring units represented by the formula: ##STR1## wherein A, B, C and D are independently selected from the group consisting of hydrogen, CH.sub.2 PO.sub.3 H.sub.2, (CH.sub.2).sub.n COOH, (CH.sub.2).sub.m SO.sub.3 H and water-soluble salts thereof, wherein n=1 to 4, m=1 to 4, X is 1 to 99 mol %, Y is 1 to 99 mol % and X+Y=100 and with the proviso that when A is hydrogen, B is (CH.sub.2).sub.n COOH, or (CH.sub.2).sub.m SO.sub.3 H and at least one of C and D is CH.sub.2 PO.sub.3 H.sub.2 or (CH.sub.2).sub.m SO.sub.3 H, when A is (CH.sub.2).sub.n COOH, at least one of B, C and D is CH.sub.2 PO.sub.3 H.sub.2 or (CH.sub.2).sub.m SO.sub.3 H and when A is CH.sub.2 PO.sub.3 H.sub.2, at least one of B, C or D is (CH.sub.2).sub.n COOH or (CH.sub.2).sub.m SO.sub.3 H. The compositions of this invention are useful in water treatment to inhibit or remove scale deposits.
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: May 13, 1997
    Assignee: BetzDearborn Inc.
    Inventor: Lawrence L. Kuo
  • Patent number: 5593595
    Abstract: 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.
    Type: Grant
    Filed: October 6, 1995
    Date of Patent: January 14, 1997
    Assignee: Calgon Corporation
    Inventor: Jasbir S. Gill
  • Patent number: 5580462
    Abstract: 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.
    Type: Grant
    Filed: October 6, 1995
    Date of Patent: December 3, 1996
    Assignee: Calgon Corporation
    Inventor: Jasbir S. Gill
  • Patent number: 5565106
    Abstract: Polyether polyamino methylene phosphonates, which possess high calcium tolerance and have been found to give excellent inhibition of the formation, deposition and adherence of scale-forming salts, especially calcium carbonate, in aqueous systems involving severe conditions which include elevated pH, high dissolved solids content, and high saturation levels of calcium carbonate, are degraded by the oxidizing biocides bromine and chlorine used to control microbial growth in such aqueous systems. It has been found that organic sulfonamides provide excellent protection against such degradation when they are added to the aqueous system along with the polyether polyamino methylene phosphonate scale inhibitors.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: October 15, 1996
    Assignee: Calgon Corporation
    Inventors: Ann M. Sherbondy, Daniel P. Vanderpool
  • Patent number: 5534157
    Abstract: A method for inhibiting the formation, deposition, and adherency of scale-forming salts, including calcium sulfite, in process waters. The method is particularly suited for use in pulp mill lime kiln flue gas scrubber systems and multi-effect evaporators. Additionally, the method is effective at high pH and high calcium sulfite saturation levels.
    Type: Grant
    Filed: November 10, 1994
    Date of Patent: July 9, 1996
    Assignee: Calgon Corporation
    Inventors: Craig D. Iman, Robert E. Tomilson
  • Patent number: 5527863
    Abstract: Copolymers of polyaspartic acid which are suitable for the inhibition of scale deposition were obtained by reacting maleic acid, an additional polycarboxylic acid and ammonia in a stoichiometric excess, at 120.degree.-350.degree. C., preferably 180.degree.-300.degree. C., to provide copolymers of polysuccinimide. In a second embodiment, a polyamine was added to the reaction mix. These intermediate polysuccinimide copolymers could then be converted to the salts of copolymers of polyaspartic acid by hydrolysis with a hydroxide.Such copolymers are useful in preventing deposition of scale from water and find applications in treating water. Other applications include scale prevention additives for detergents. In addition, such copolymers inhibit dental tartar and plaque formation.
    Type: Grant
    Filed: January 27, 1995
    Date of Patent: June 18, 1996
    Assignee: Bayer AG
    Inventors: Louis L. Wood, Gary J. Calton
  • Patent number: 5525257
    Abstract: An improved composition for water treatment and for alkaline cleaning contains polyaspartic acid or a derivative thereof and a polycarboxylic acid.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: June 11, 1996
    Assignee: Bayer AG
    Inventors: Roland Kleinstuck, Hermann Sicius, Torsten Groth, Winfreid Joentgen
  • Patent number: 5518629
    Abstract: A method of controlling scale formation and deposition and corrosion in aqueous systems is described wherein a treatment solution of a substoichiometric amount of a scale/corrosion inhibitor in combination with a substituted alkylpolycarboxylate is employed. The scale/corrosion inhibitor can be a phosphonate such as hydroxyethylidene diphosphonic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, hydroxyphosphonoacetic acids, amino phosphonates; terpolymers, copolymers and homopolymers of acrylic acid, maleic acid, epoxysuccinic acids such as polyepoxysuccinic acid or mixtures thereof. The substituted alkylpolycarboxylates are compounds of the general structure: R--X--Y.sub.n wherein R is a hydrocarbon functionality having 4 to 18 carbons; X, when present, is --NH--, --NY.sup.1 --, --N-->O, --N--OC--Y.sup.1, --O-- or --S--; n is greater than or equal to 1; and Y and Y.sup.
    Type: Grant
    Filed: November 29, 1994
    Date of Patent: May 21, 1996
    Assignee: Betz Laboratories, Inc.
    Inventors: Libardo A. Perez, William S. Carey, Donald T. Freese, Judith B. Rockett
  • Patent number: 5506335
    Abstract: Sulfonic acid group-containing polyaspartic acid derivatives, some of which are novel, having repeating units of the structures I and II ##STR1## in whichR.sup.1 has the meaning given in the description, are suitable for water treatment and as a detergent additive.
    Type: Grant
    Filed: November 9, 1994
    Date of Patent: April 9, 1996
    Assignee: Bayer AG
    Inventors: Hermann Uhr, Lutz Heuer, Torsten Groth, Winfried Joentgen, Roland Kleinstuck
  • Patent number: 5496914
    Abstract: Polymers of maleic, fumaric or malic acids or maleic, fumaric or malic acid and ammonia with amino acids are prepared by heating at 180.degree.-350.degree. C., preferably 200.degree.-300.degree. C. The polymer formed may be converted to a salt by hydrolysis with a metal hydroxide or ammonium hydroxide.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: March 5, 1996
    Assignee: SRCHEM, Inc.
    Inventors: Louis L. Wood, Gary J. Calton
  • Patent number: 5490942
    Abstract: A process of inhibiting oxalate scale formation in aqueous systems is disclosed. A preferred class of scale inhibitors is represented by polyamino hexamethylene phosphonates. These phosphonate inhibitors can be used in levels of from 0.05 ppm to 300 ppm (of the aqueous solution) at pH in the near neutral to preferably alkaline medium.
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: February 13, 1996
    Assignee: Monsanto Company
    Inventor: Krzysztof Kuczynski
  • Patent number: 5486294
    Abstract: Disclosed is a method of inhibiting the formation of scales such as barium and strontium sulfate in low pH aqueous system. The method involves treating the aqueous system with a scale control treatment including polyepoxysuccinic acid. Typical low pH aqueous systems where the present invention is particularly useful are oilfield produced water, resin bed water softeners during acid regeneration operations.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: January 23, 1996
    Assignee: Betz Laboratories, Inc.
    Inventor: J. Michael Brown
  • Patent number: 5478476
    Abstract: Certain N-bis(phosphonomethyl) amino acids are novel compounds and are useful in preventing calcium carbonate scale.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: December 26, 1995
    Assignee: Nalco Chemical Company
    Inventor: Vera Dragisich
  • Patent number: 5470942
    Abstract: There is disclosed a process for preparing polyaspartic acid by thermal condensation of L-aspartic acid in a novel catalyst which shortens the reaction time and increases the molecular weight of the polymer. The novel catalyst is a catalytically effective methylenephosphonic acid. Typical catalysts are 1-hydroxyethylidene-1,1-diphosphonic acid and aminotris(methylenephosphonic acid). The methylenephosphonic acid is blended with the amino acid in a molar ratio of amino acid to catalyst in the range of from about 1:1 to 40:1.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: November 28, 1995
    Assignee: Monsanto Company
    Inventors: Gregory C. Alexander, Mark E. Jason, Dennis J. Kalota
  • Patent number: 5462668
    Abstract: Additives are usually diluted before they are added to a geothermal brine processing stream. It has been found that one preferred diluent is the conditioned steam condensate produced after power generation in the geothermal plants. One class of additives beneficially diluted by the conditioned steam condensate are crystal structure modifiers. When it is diluted with the steam condensate, the heat-sensitive crystal structure modifier is prevented from being degraded by the heat of the brine so that when blended with the geothermal brine the crystal structure modifier can perform its function of inhibiting the precipitation of alkaline earth salts.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: October 31, 1995
    Assignee: Union Oil Company of California
    Inventors: Darrell L. Gallup, John L. Featherstone, Carl E. Flint
  • Patent number: 5454954
    Abstract: A composition useful as a deposit control agent to control the formation, deposition and adherence of scale in the process of extracting precious metals from an ore comprising (I) an aqueous slurry of a mining circuit having the ore, and (II) from about 5 to 500 ppm, based on the total weight of (I), of (a) from about 50 to 100 weight percent, based on the weight of (II), of a polyether polyamino methylene phosphonate, and (b) from about 0.1 to 50 weight percent, based on the weight of (II), of a polymer. A method for inhibiting calcium scale in one or more aqueous systems of a mining circuit employing this composition is also provided.
    Type: Grant
    Filed: November 2, 1994
    Date of Patent: October 3, 1995
    Assignee: Calgon Corporation
    Inventors: Nicholas J. Alfano, David M. Shenberger
  • Patent number: 5413718
    Abstract: Geothermal brines are extracted from the earth, flashed and the remaining liquids are injected back into the earth. Although it would be advantageous for resource maintenance to inject the same amount of liquid as extracted, addition of liquid causes massive system upsets that prevent such addition. River or other similar surface waters can now be added to the brine stream created when extracting power from a geothermal source, after adding a crystal structure modifier to the brine stream. In operations where the brine stream is returned to the earth, the weight rate of the brine injected into the earth is brought to at least 90% what it was when extracted from the ground.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: May 9, 1995
    Assignee: Union Oil Company of California
    Inventors: Darrell L. Gallup, John L. Featherstone
  • Patent number: 5409614
    Abstract: NORMs are inhibited or prevented from precipitating with scale produced by a hot aqueous solution by adding multiple portions of a crystal structure modifier to the aqueous solution as it cools before and during removal of silicon containing components by precipitation. Preferred crystal structure modifiers include polyacrylate crystal structure modifiers and phosphonomethylated amines.
    Type: Grant
    Filed: July 16, 1993
    Date of Patent: April 25, 1995
    Assignee: Union Oil Company of California
    Inventors: Darrell L. Gallup, John L. Featherstone
  • Patent number: 5407597
    Abstract: A white rust inhibiting composition and method of inhibiting white rust for evaporative water coolers are disclosed. The composition includes in combination a blend of one or more organophosphorus compounds, one or more carbamate compounds, and one or more water soluble metal compounds.
    Type: Grant
    Filed: April 22, 1994
    Date of Patent: April 18, 1995
    Assignee: Fremont Industries, Inc.
    Inventors: Bruce D. Busch, Michael Oldsberg
  • Patent number: 5401419
    Abstract: The present invention relates to operation of residential or commercial evaporative coolers, more specifically, its subject matter is conservation of water needed to cool down ambient air in their operation.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: March 28, 1995
    Inventor: Sidney Z. Kocib
  • Patent number: 5391303
    Abstract: Polyether polyamino methylene phosphonate N-oxides possess high calcium tolerance and have been found to give excellent inhibition of the formation, deposition and adherence of scale-forming salts, especially calcium carbonate, under severe conditions which include elevated pH, high dissolved solids content, and high saturation levels of calcium carbonate.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: February 21, 1995
    Assignee: Calgon Corporation
    Inventor: Raymond J. Schaper
  • Patent number: 5378368
    Abstract: Polyether polyamino methylene phosphonates, when added to various industrial water systems in concentrations between 0.1 mg/L and 50 mg/L, control silica/silicate deposition. 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.
    Type: Grant
    Filed: August 5, 1992
    Date of Patent: January 3, 1995
    Assignee: Calgon Corporation
    Inventor: Jasbir S. Gill
  • Patent number: 5376331
    Abstract: A method of inhibiting the pitting corrosion rate of carbon steel in a cooling tower system comprising adding to a cooling tower water an effective amount of a corrosion inhibiting composition containing from about 1 to about 10 ppm of a water soluble molybdate, calculated as molybdate and from about 5 to about 25 ppm of a stabilized phosphate, calculated as phosphate, the corrosion inhibiting composition being substantially free of active zinc, and circulating the water in the system.
    Type: Grant
    Filed: April 16, 1993
    Date of Patent: December 27, 1994
    Assignee: Gulf Coast Performance Chemical, Inc.
    Inventors: Bradley A. Bucher, Jesse H. Jefferies
  • Patent number: 5368830
    Abstract: Calcium carbonate scale deposits, occurring in gold and silver mining involving the cyanidation process which utilizes heap and vat leaching, and carbon-in-pulp, carbon-in-leach, particularly activated carbon separation columns; said scale deposits forming on the carbon surfaces and in the emitters and sprinklers of the heap leaching system, are controlled using polyether polyamino methylene phosphonates, which provide effective inhibition despite the severe conditions encountered in these systems, including very high pH's.
    Type: Grant
    Filed: October 15, 1992
    Date of Patent: November 29, 1994
    Assignee: Calgon Corporation
    Inventors: Nicholas J. Alfano, Bennett P. Boffardi
  • Patent number: 5360550
    Abstract: A method of inhibiting the precipitation of barium scale from an aqueous system, comprising adding to the aqueous system a product having the formula I: ##STR1## in which M is hydrogen or an alkali metal ion, an ammonium ion or a quanternized amine radical; R.sub.1 is hydrogen or methyl; and n is an integer having an average value ranging from 4 to 20.
    Type: Grant
    Filed: November 18, 1993
    Date of Patent: November 1, 1994
    Assignee: FMC Corporation
    Inventors: Brian G. Clubley, Jan Rideout
  • Patent number: RE36291
    Abstract: A method for inhibiting corrosion of metal surfaces in an aqueous medium, comprising incorporating into the medium a corrosion inhibitor in an amount sufficient to inhibit corrosion, the corrosion inhibitor comprising a water-soluble agent selected from the group consisting of compositions of the formula ##STR1## compositions of the formula ##STR2## and mixtures thereof, wherein R is R.sup.2 .paren open-st.OCH.sub.2 CH.sub.2 .paren close-st..sub.x, wherein R.sup.2 is a substituted or unsubstituted alkyl, aryl, or aralkyl group of from about five to about fifteen carbon atoms, each carbon atom having at least one hydrogen and x is an integer of from about one to about ten, and R'N is a basic nitrogen compound that is at least water-dispersible.
    Type: Grant
    Filed: December 12, 1995
    Date of Patent: September 7, 1999
    Assignee: Baker Hughes Incorporated
    Inventor: Richard L. Martin