For Scale Inhibiting Or Corrosion Preventing Patents (Class 203/7)
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Patent number: 5866011Abstract: A method of treating water to inhibit the formation of salt scale is disclosed. The method is particularly effective at inhibiting the formation and deposition of mineral salts in brine concentration and evaporation systems. The method comprises introducing into the system a polyepoxysuccinic acid of the general formula: ##STR1## where n ranges from about 2 to about 50, M is hydrogen or a water soluble cation such as Na.sup.+, NH.sub.4.sup.+ or K.sup.+ and R is hydrogen, C.sub.1-4 alkyl or C.sub.1-4 substituted alkyl.Type: GrantFiled: April 30, 1997Date of Patent: February 2, 1999Assignee: BetzDearborn Inc.Inventor: Gregory J. McGiffney
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Patent number: 5858176Abstract: Methods and compositions for inhibiting fouling in vinyl monomers are disclosed. Alkylphosphonate esters or acids thereof are added to vinyl monomers, particularly ethylene dichloride, that are undergoing processing to inhibit fouling.Type: GrantFiled: April 22, 1997Date of Patent: January 12, 1999Assignee: BetzDearborn Inc.Inventor: Graciela B. Arhancet
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Patent number: 5681432Abstract: Methods for inhibiting organic fouling of heat transfer surfaces in contact with an alcohol distillation stream are discussed. The methods include adding to the alcohol distillation stream an effective inhibiting amount of a treatment including a high molecular weight anionic polymer.Type: GrantFiled: October 25, 1995Date of Patent: October 28, 1997Assignee: BetzDearborn Inc.Inventors: William J. Palardy, Nancy A. DiAngelo
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Patent number: 5676801Abstract: A radial-inflow large volume-rate low pressure-differential, single-stage compressor comprising 2 periphiral concentric sets of axial blades spaced circumferentially between two supporting rings and further strengthened against bending by intermediate rings if necessary. The outer set of blades rotates to impart energy to the working fluid and the inner set is stationary to recover kinetic energy. Stationary guide surfaces concentric with the blades direct the radially inward flow to axial. A diverging duct recovers further the kinetic energy. The compressor fills the pressure-ratio gap between blowers and turbo-compressors. Its use in desalination instead of the currently used centrifugal compressors, can scale-up the vapor-compression unit-size to more than three fold.Type: GrantFiled: February 6, 1995Date of Patent: October 14, 1997Inventor: Yehia El-Sayed
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Patent number: 5659095Abstract: A polymerization inhibitor composition for inhibiting the polymerization of aromatic vinyl monomers at elevated temperatures comprising:(a) a benzofuroxan derivative of the formula ##STR1## wherein R is C.sub.1 -C.sub.4 alkyl or alkoxy; R.sup.1 is a nitro group; and m and n are each independently 0, 1, or 2; and(b) a solvent selected from the group consisting of toluene, xylene, ethylbenzene, vinyltoluene, divinylbenzene, alpha-methylstyrene, and a C.sub.12 -C.sub.18 hydrocarbon,and methods for inhibiting the polymerization of aromatic vinyl monomers at elevated temperatures using this composition.Type: GrantFiled: March 13, 1996Date of Patent: August 19, 1997Assignee: Uniroyal Chemical Company, Inc.Inventors: Howard Stephen Friedman, Gerald John Abruscato, John Matthew DeMassa, Anthony Vincent Gentile, Anthony Vincent Grossi
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Patent number: 5641396Abstract: 2-amino-1-methoxypropane is used as a neutralizing amine in crude oil distillation units. The amine of the invention gives superior neutralization at the first initial condensate compared to other commonly used neutralizing amines.Type: GrantFiled: September 18, 1995Date of Patent: June 24, 1997Assignee: Nalco/Exxon Energy Chemicals L. P.Inventors: Veronica K. Braden, Tannon S. Woodson
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Patent number: 5622605Abstract: A process and apparatus for desalinating seawater or brine and purifying water which contains minerals, salts, and other dissolved solids while simultaneously generating power. The salinous water is heated in a boiler to form steam and a concentrated brine. The concentrated brine is removed from the boiler, the steam produced in the boiler is washed with fresh water to remove trace salts and inorganic materials, and water bearing trace salts and inorganic materials are returned to the boiler. The washed steam is expanded across a turbine to generate electrical or mechanical power which is utilized as a product. The steam exhausted from the turbine is collected and condensed, and one portion of the condensed water is utilized as a fresh water product and another portion of the condensed water is used as the wash water to wash the steam produced in the boiler. Energy efficiency is improved by heat exchanging the hot concentrated brine against the salinous feed water or by flashing the brine to produce steam.Type: GrantFiled: April 10, 1995Date of Patent: April 22, 1997Inventors: Gary D. Simpson, Karl Lin
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Patent number: 5616217Abstract: In the manufacture of MTBE from TBA and methanol, acidic by-products formed during the etherification reaction are removed by fractionating the etherification reaction product in a first MTBE distillation column to provide a first lower boiling distillation fraction comprising isobutylene, MTBE, methanol and acidic by-products and a first higher boiling distillation fraction comprising methanol, TBA and water, fractionating the first higher boiling distillation fraction in a recycle distillation column to provide a lower boiling TBA recycle fraction and a higher boiling water fraction, recycling the higher boiling water fraction to the MTBE distillation column at a charge point above the charge point for the etherification reaction product, and adding aqueous sodium hydroxide to the recycled higher boiling water fraction in an amount sufficient to neutralize the acidic by-products charged to the MTBE distillation column.Type: GrantFiled: August 17, 1995Date of Patent: April 1, 1997Assignee: Texaco Chemical Inc.Inventor: Mark E. Taylor
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Patent number: 5578173Abstract: A method of removing dimethyl terephthalate (DMT) from a vapor stream. The vapor stream includes dimethyl terephthalate (DMT), methylhydroxyethyl terephthalate (MHET), glycols and methanol. A distillation column is held under an elevated pressure of 100 to 500 kPag and at a temperature of at least 85.degree. C. It has (i) a plurality of distillation trays; (ii) methanol liquid sprays between the trays; (iii) a main spray zone below the trays and (iv) a liquid pool of methanol in the bottom of the column. The vapor stream is directed into the distillation column, above the liquid pool and below the main spray zone, thereby forming a stream of liquid and vapor. The stream of liquid is directed away from the distillation column walls and into the liquid pool at the bottom of the column.Type: GrantFiled: April 3, 1995Date of Patent: November 26, 1996Assignee: Eastman Kodak CompanyInventors: Walter E. Toot, Jr., Brian L. Simpson, Bruce R. Debruin, Andrius A. Naujokas, William J. Gamble
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Patent number: 5556575Abstract: Disclosed are a method for inhibiting corrosion in crude oil distillation towers, an improvement in crude oil fractionation, a method for dispersing iron sulfide in a hydrocarbon stream and a hydrocarbon dispersion using the reaction product of hydrocarbyl succinic anhydride and an amine. The reaction product has a molecular weight of from 500-800, the hydrocarbyl substituent has 6-20 carbon atoms, and the amine is selected from EDA, DETA, TETA, TEPA, PEHA, AEP, piperazine, 1,2-PDA, 1,3-PDA, IBPA, MDA or HMDA. The imide product is a filming inhibitor used to treat metal surfaces subject to mineral acid corrosion and disperse iron sulfide particles by adding 3 to 24 ppm to sweet or sour crude contacting the metal surfaces.Type: GrantFiled: March 30, 1995Date of Patent: September 17, 1996Assignee: Nalco/Exxon Energy Chemicals L.P.Inventors: Elizabeth Babaian-Kibala, Veronica K. Braden, Michael K. Poindexter, Christopher J. Murphy
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Patent number: 5552085Abstract: Corrosion of the metallic surfaces of distillation columns, trays, packing, and pumparound piping used in the production of hydrocarbons can be controlled by adding a neutralized or non-neutralized thio-phosphate or thio-phosphite ester to the hydrocarbon distillate contacting the metallic surfaces.Type: GrantFiled: October 3, 1995Date of Patent: September 3, 1996Assignee: Nalco Chemical CompanyInventor: Elizabeth Babaian-Kibala
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Patent number: 5531937Abstract: Compositions and a method of using the compositions to inhibit corrosion. The compositions are water soluble n-alkyl morpholine, saturated dicarboxylic acid, optionally alkanol amine and optionally surfactant compositions which inhibit ferrous metal corrosion when added to aqueous oxygen-free solutions.Type: GrantFiled: September 12, 1995Date of Patent: July 2, 1996Assignee: Betz Laboratories, Inc.Inventors: Ljiljana V. Minevski, Edmund J. Bockowski
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Patent number: 5405503Abstract: A process and apparatus for desalinating seawater or brine and purifying water which contains minerals, salts, and other dissolved solids while simultaneously generating power. The salinous water is heated in a boiler to form steam and a concentrated brine. The concentrated brine is removed from the boiler, the steam produced in the boiler is washed with fresh water to remove trace salts and inorganic materials, and water bearing trace salts and inorganic materials are returned to the boiler. The washed steam is expanded across a turbine to generate electrical or mechanical power which is utilized as a product. The steam exhausted from the turbine is collected and condensed, and one portion of the condensed water is utilized as a fresh water product and another portion of the condensed water is used as the wash water to wash the steam produced in the boiler. Energy efficiency is improved by heat exchanging the hot concentrated brine against the salinous feed water or by flashing the brine to produce steam.Type: GrantFiled: November 5, 1993Date of Patent: April 11, 1995Inventors: Gary D. Simpson, Karl Lin
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Patent number: 5368830Abstract: 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: GrantFiled: October 15, 1992Date of Patent: November 29, 1994Assignee: Calgon CorporationInventors: Nicholas J. Alfano, Bennett P. Boffardi
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Patent number: 5336414Abstract: Methods for controlling the formation of proteinaceous fouling deposits in high temperature evaporators and concentrators as employed in processing steepwater in the wet milling of corn. The methods comprise adding lecithin, or a long chain fatty acid to the steepwater in an amount ranging from about 150 parts per million to about 500 parts per million steepwater.Type: GrantFiled: March 17, 1993Date of Patent: August 9, 1994Assignee: Betz Laboratories, Inc.Inventor: Nancy A. DiAngelo
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Patent number: 5324393Abstract: A method for preventing fouling of ethylene dichloride distillation units which comprises treating the feed to such unit with a fouling preventing amount of a composition comprising (a) 2-15 weight % of an oil soluble polyacrylate ester or methacrylate ester with alcohol radical of the ester group containing from C.sub.4 -C.sub.22 carbon atoms which contains between 0.1-25 mole % of amino alcohol ester groups; (b) 20-40 weight % a phenylene diamine compound having the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are the same or different and are hydrogen, C.sub.1 -C.sub.20 alkyl, C.sub.1 -C.sub.20 aryl, C.sub.1 -C.sub.20 alkaryl or C.sub.1 -C.sub.20 aralkyl, with the proviso that at least one of R.sub.1, R.sub.2, R.sub.3 or R.sub.4 is hydrogen; and (c) the balance is a heavy aromatic solvent.Type: GrantFiled: April 15, 1993Date of Patent: June 28, 1994Assignee: Nalco Chemical CompanyInventor: Michael K. Poindexter
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Patent number: 5282956Abstract: A method for the inhibition and removal Of ammonium chloride deposition in hydrocarbon processing units comprising adding to the hydrocarbon liquid an amide selected from the group consisting of dimethylformamide and 1,3-dimethyl-2-thiourea.Type: GrantFiled: July 7, 1992Date of Patent: February 1, 1994Assignee: Betz Laboratories, Inc.Inventor: Carl E. Weaver
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Patent number: 5269908Abstract: In a process for the separation of hydrocarbon materials and other materials including ammonia and hydrogen chloride normally associated with the hydrocarbon materials in refining of petroleum, the deposition of ammonium chloride is retarded or prevented by introducing inert gas of higher volatility into the processing operation upstream from where the deposition of ammonium chloride would otherwise occur.Type: GrantFiled: August 27, 1992Date of Patent: December 14, 1993Assignee: Nalco Canada Inc.Inventor: Bordan W. Krupay
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Patent number: 5268073Abstract: In concentrating solutions containing 1 to 10% by weight of salts and resins, the yield and economics and trouble-free running can be improved by using a flow tube which has a steady curvature at least in the last third and is sized in its diameter in such a way that the mean flow velocity at the tube outlet is at least 50 m/second, and at least 90% by weight of the vaporizable components are evaporated off at driving temperature gradients of 20.degree. to 200.degree. C. between the heating medium and the solution.Type: GrantFiled: October 7, 1992Date of Patent: December 7, 1993Assignee: Bayer AktiengesellschaftInventors: Clemens Casper, Jorgen Weinschenck
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Patent number: 5262013Abstract: A coolant recycling apparatus has a boiler and condenser for distilling a glycol and water from a used coolant. The glycol and water are recombined in a mixing tank to form a mixture having a desired ratio of water to glycol, and an inhibitor is added to the mixture to obtain a fresh coolant mixture ready for use in an engine cooling system. Contaminants in the used coolant are concentrated to form a sludge.Type: GrantFiled: July 17, 1991Date of Patent: November 16, 1993Assignee: Amalgamated Technologies, Inc.Inventors: Roy E. Beal, Scott A. McCracken
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Patent number: 5256276Abstract: A method for the inhibition and removal of ammonium chloride deposition in hydrocarbon processing units comprising adding a phosphatide to the hydrocarbon liquid. A preferred phosphatide is lecithin.Type: GrantFiled: May 18, 1992Date of Patent: October 26, 1993Assignee: Betz Laboratories, Inc.Inventor: Carl E. Weaver
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Patent number: 5250151Abstract: An evaporation assembly for concentrating liquids having an evaporation area for conveying a liquid to be concentrated and a heating system for heating and concentrating the liquid conveyed through the evaporation area. The evaporation area includes a liquid inlet for introducing liquid to be concentrated into the evaporation area, and a liquid and vapor outlet for conveying the liquid through the evaporation area. A vapor circulating system is coupled between the liquid inlet end and the liquid and vapor outlet of the evaporation area for increasing the velocity of the liquid to be concentrated for impeding or removing precipitated particles or deposits from the heat exchange surfaces.Type: GrantFiled: March 6, 1992Date of Patent: October 5, 1993Inventor: Joaquin Huercanos
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Patent number: 5211840Abstract: A process for adding an amine having a pKa of between 5 and 8 to a petroleum refinery distillation unit for the purpose of neutralizing acidic species contained in the hydrocarbon feedstock. The use of these amines raises the dew point pH sufficiently to prevent corrosion of the metallic surfaces of the overhead equipment while reducing the potential for the precipitation of amine salts.Type: GrantFiled: May 8, 1991Date of Patent: May 18, 1993Assignee: Betz Laboratories, Inc.Inventors: Scott E. Lehrer, James G. Edmondson
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Patent number: 5188179Abstract: A system and method for inhibiting corrosion of oil field pipe exposed to corrosive material including hydrogen sulfide, carbon dioxide, and sodium chloride with a corrosion inhibiting film which is a precipitate film formed by the reaction of a polysulfide with ferrous iron. The ferrous iron may be a constituent of the fluid passing through the pipe or separately injected. The polysulfide is the reaction product of hydrogen sulfide as a constituent existing in the passing fluid and an oxidizing agent such as ammonium nitrate separately introduced into the passing fluid. The method includes the steps of continuously passing a fluid carrying corrodents through the pipe, continuously bringing a polysulfide into being within the fluid, and continuously bringing elemental ferrous iron into reaction with the polysulfide within the passing fluids to form a precipitated film which is an effectively amorphous film having a predominant amount of iron disulfide.Type: GrantFiled: December 23, 1991Date of Patent: February 23, 1993Inventors: Richard J. Gay, Charles C. Gay, Veronique M. Matthews, Francoise E. M. Gay, Valerie Chase
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Patent number: 5182013Abstract: Naphthenic acid corrosion in refinery distillation units is inhibited by introducing into the units effective amounts of a polysulfide corrosion inhibitor.Type: GrantFiled: December 21, 1990Date of Patent: January 26, 1993Assignee: Exxon Chemical Patents Inc.Inventors: Philip R. Petersen, Frederick P. Robbins, III, William G. Winston
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Patent number: 5178734Abstract: A water distilling apparatus (10) which includes vertically stacked components, i.e. an uppermost water storage tank (12), an intermediate boiling tank (14) and a lowermost condensing unit (16). Stacking of the distiller components creates a space efficient design with ready access to the respective components. The preferred apparatus (10) is also equipped with a small, dedicated water conditioning unit (20) situated between the main solenoid water valve (94) and the inlet of the boiling tank (14).Type: GrantFiled: February 16, 1990Date of Patent: January 12, 1993Assignee: International Water Technologies, Inc.Inventor: David G. Palmer
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Patent number: 5156706Abstract: A vertical tube evaporation process for the concentration of saline water and other liquids, including the addition of an anionic mono-molecular dispersant thereto which interacts with materials precipitated during concentration and inhibits the formation of scale or fouling depositions on evaporator surfaces, and wherein the additive is incorporated into the precipitated materials and improves their removal during the descaling or defouling of evaporator surfaces by rendering such precipitates redispersable in fresh water or in a non-saturated liquid used for descaling or defouling of evaporator surfaces.Type: GrantFiled: April 29, 1988Date of Patent: October 20, 1992Inventor: Hugo H. Sephton
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Patent number: 5133837Abstract: A multi-stage flash evaporator is constructed so that the evaporator elements are dimpled plates mounted so that they extend horizontally. One, two, or more sets of plates may be mounted in each evaporator stage, the sets stacked upon one another in a tier arrangement. Each stage may be formed by a circular cross-section vessel, with I-beams--or like supports--extending horizontally at about the horizontal diameter of the vessel, and supporting the dimpled plates on them. A condensate collection trough is mounted below the dimpled plates and at the I-beams, the I-beams having openings in them through which condensate collected by the trough passes from one end of the vessel to the other. The hot liquid --such as sea water to be desalinated--to be evaporated is passed into a bottom chamber of each stage vessel, with vapor flowing upwardly through demistors and channels, into contact with the dimpled plates, and the condensate falling as a thin film down the plates and collecting in the condensate trough.Type: GrantFiled: September 10, 1990Date of Patent: July 28, 1992Assignee: Kamyr, Inc.Inventors: Carl L. Elmore, Kyle D. Infante
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Patent number: 5110997Abstract: A method of inhibiting fouling in a crude ethylene dichloride stream comprises introducing into the stream an inhibiting amount of an antifoulant selected from (A) an acylated amine (e.g., reaction product of polyisobutylene and maleic anhydride) and a polyamine (B) magnesium alkyl aryl sulfonate, and (C) a mixture of A and B.Type: GrantFiled: April 19, 1991Date of Patent: May 5, 1992Assignee: Exxon Chemical Patents Inc.Inventor: Ghazi B. Dickakian
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Patent number: 5104491Abstract: Crude pentachloronitrobenzene containing hexachlorobenzene and small amounts of acids is treated in the molten state or in a mixture solution of nitrobenzene or chloronitrobenzenes with an inorganic basic substance and then subjected to a distillation under reduced pressure.Type: GrantFiled: March 12, 1991Date of Patent: April 14, 1992Assignee: Mitsui Toatsu Chemicals, Inc.Inventors: Mitsumasa Umemoto, Ryuichi Mita, Yoshitsugu Kono, Hiroshi Maeda
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Patent number: 5021128Abstract: A control for a water distillation apparatus admits untreated feed water to the boiling tank in response to a demand for the production of distilled water and operates the heater to produce steam. Level probes in the boiling tank monitors the level of untreated water in the boiling tank and admits more feed water as necessary. When demand for production of distilled water has ceased, the heater is deenergized and the boiling tank is filled to dilute the residual water in the tank and lower its temperature prior to drainage to prevent damage to a plastic house drain. In a preferred embodiment, feed water is admitted to the boiling tank in large batches and the production of distilled water continues uninterrupted until the entire batch is distilled to conserve heat energy even if demand ceases during such batch distillation. A cleaning mode is provided to remove scale from the interior of the boiling tank with a simplified manual cleaning procedure.Type: GrantFiled: February 25, 1988Date of Patent: June 4, 1991Assignee: Pure Water, Inc.Inventor: David G. Palmer
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Patent number: 4980031Abstract: Hydrogen chloride evolution is reduced in the distillation of chloroform from its admixture with an amide solvent when in contact with stainless steel, by incorporation of certain tertiary aliphatic amines.Type: GrantFiled: February 6, 1990Date of Patent: December 25, 1990Assignee: E. I. Du Pont de Nemours and CompanyInventor: David J. Rodini
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Process for decreasing the tendency to form deposits in plants for evaporating spent sulfite liquors
Patent number: 4941946Abstract: A process for decreasing the tendency to form deposits in plants for evaporating spent sulfite liquors used to produce woodpulp. In the process, the liquors are treated with polyacrylic acids having a low molecular weight. In order to prevent virtually any deposition and to increase the evaporation rate, an aqueous solution of polyacrylic acid having a low molecular weight is added to the spent sulfite liquor in an entrance stage of the multiple-effect sulfite liquor in an entrance stage of the multiple-effect evaporating system and an aqueous solution of a copolymer of sulfonated styrene and maleic anhydride or an aqueous solution of a polyacrylic acid having a low molecular weight is added to the spent sulfite liquor in at least one succeeding stage of the multiple-effect evaporating system.Type: GrantFiled: February 6, 1989Date of Patent: July 17, 1990Assignee: Metallgesellschaft AktiengesellschaftInventors: Manfred Henn, Klaus Begerow, Volker Wichert -
Patent number: 4929361Abstract: Methods for controlling the formation of proteinaceous fouling deposits in high temperature evaporators and concentrators as employed in processing steepwater in the wet milling of corn. The methods comprise adding a surfactant, preferably a nonionic surfactant to the steepwater. Particularly effective surfactants are oxyalkylated sorbitan R surfactants where R is monooleate, trioleate, monostearate, tristearate, monopalmitate and monolaurate.Type: GrantFiled: May 25, 1989Date of Patent: May 29, 1990Assignee: Betz Laboratories, Inc.Inventor: David M. Polizzotti
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Patent number: 4836891Abstract: A method for concentrating salt water. Salt water is separated from oil-water mixture which has been produced from a well. Salt water is introduced into a recirculating weir and mixed with more concentrated brine. Brine is recirculated through a thermal syphon apparatus. Recirculation includes passing brine, including some salt water, from weir into boiler vessel. Brine is heated within boiler vessel to a boiling temperature whereby brine, while boiling, generates steam which passes up out of weir. All of foregoing steps are performed at atmospheric pressure. The density of brine is sensed at a location in the lower vicinity of weir. Concentrated brine is released from lower vicinity when density at sensed temperature is at a level corresponding to a brine concentration near the precipitation of salt from solution. Salt water and brine is passed through a magnetic water treating unit. The concentrated brine, as released, is passed into a holding vessel.Type: GrantFiled: May 19, 1986Date of Patent: June 6, 1989Assignee: Evaporation, Inc.Inventors: James H. Files, Donald M. Harrel, John M. Montague, Thomas L. Stansbury Sr., Carlton T. Sikes
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Patent number: 4806229Abstract: A process for substantially neutralizing the volatile acid gases and water present in the condensate of a distilling pertroleum product which comprises treating the distilling product prior to the condensation thereof with at least one amine having a boiling point below 95.degree. C.Type: GrantFiled: October 3, 1986Date of Patent: February 21, 1989Assignee: Nalco Chemical CompanyInventors: Sam Ferguson, Kathryn G. Burns, Russell C. Strong
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Patent number: 4795532Abstract: A method and apparatus for treating the distilled water obtained from an evaporation process sea water desalination plant is provided wherein carbon dioxide is extracted from sea water in the high temperature stages of the desalination plant and where the carbon dioxide thus extracted is dissolved into the water, along with calcium, thereby converting the distilled water into the quality suited for city tap water.Type: GrantFiled: February 13, 1987Date of Patent: January 3, 1989Assignee: Sasakura Engineering Co. Ltd.Inventors: Junji Mizutani, Kozo Fujita
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Patent number: 4758311Abstract: A method for passivating the surface of the strippers of the urea plants, where the temperatures are very high, where the pressures range from 120 to 240 Kg/cm.sup.2 and where the effluent process flow from the synthesis reactor undergoes one or more falling-film evaporations, preferably in countercurrent with a driving gas consisting of NH.sub.3 or CO.sub.2, characterized by the fact that the passivation is carried out by means of a sinergistic combination of oxygen, preferably injected into the bottom of at least one stripper, and of a second passivating agent, preferably injected into the process flow entering the head of at least one stripper, wherein said second passivating agent is injected in the liquid state or as a liquid solution, before or contemporaneously to the start of the evaporation.Type: GrantFiled: May 11, 1987Date of Patent: July 19, 1988Assignee: Montedison S.p.A.Inventors: Giorgio Pagani, Giuseppe Faita, Ubaldo Grassini
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Patent number: 4756888Abstract: A method is disclosed for controlling the deposition of metal-containing scales, such as iron silicate scale, from a hot, aqueous, geothermal brine or the like, without substantial corrosion of brine handling equipment. The brine is contacted with (1) an amount of an acid sufficient to reduce the pH of the brine between 0.1 and 0.5 unit and (2) a greater than stoichiometric amount of a reducing agent for reducing trivalent iron and manganese cations in a high temperature brine solution to divalent ions. An overall decrease in scale deposition, especially of iron silicate scale, is achieved while a silver-rich scale can be recovered from silver-containing brines.Type: GrantFiled: December 29, 1983Date of Patent: July 12, 1988Assignee: Union Oil Company of CaliforniaInventors: Darrell L. Gallup, John W. Jost
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Patent number: 4747917Abstract: A process for reducing sulfate ion concentrations in an alkali metal halide brine to be electrolyzed in an electrolytic cell comprises feeding the alkali metal halide brines to a reaction zone containing a slurry of gypsum crystals having a concentration of at least 5 weight percent of solids to form a brine-containing slurry. An aqueous solution of a brine soluble calcium salt is admixed with the brine-containing slurry in an amount sufficient to reduce the sulfate ion concentration to a desired level. The brine-containing slurry is agitated at a pumping velocity of at least about 1.0 meters per second to release solution supersaturation by gypsum crystal formation.Type: GrantFiled: March 2, 1987Date of Patent: May 31, 1988Assignee: Olin CorporationInventors: Don E. Reynolds, Paul W. Breaux, deceased, Emily J. Reed
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Patent number: 4735787Abstract: A method of preventing scale and deposit formation on the surfaces of mist eliminators in wet scrubber flue gas desulfurization systems which utilize intermittent wash cycles which comprises coating the surfaces of these mist eliminators with a thin coating of talc.Type: GrantFiled: August 17, 1987Date of Patent: April 5, 1988Assignee: NALCO Chemical CompanyInventors: Richard J. Mouche, Mei-Jan L. Lin, Roy A. Johnson
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Patent number: 4702798Abstract: A continuous process and apparatus for drying aqueous solids by evaporation using a fluidizing oil and a surfactant wherein the fluidizing oil and surfactant are recovered and recycled separately or together. The aqueous solids may, or may not, have a heavy, natural oil associated with them.Type: GrantFiled: February 24, 1987Date of Patent: October 27, 1987Assignee: Hanover Research CorporationInventor: Anthony J. Bonanno
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Patent number: 4634532Abstract: 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: GrantFiled: September 25, 1985Date of Patent: January 6, 1987Assignee: Calgon CorporationInventors: Douglas P. Logan, Thomas E. Cornelius, III, Susan P. Rey
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Patent number: 4628836Abstract: A process is disclosed for inhibiting corrosion of metal surfaces and deposition of particulates in an air preheater system. In the process, a composition (preferably aqueous) comprising a corrosion inhibiting amine and a surfactant having an HLB value of from about 8 to about 20, preferably from about 10 to about 14, is supplied to the combustion gas-in side and/or to the air-in side of the air preheater for protection of the metal surfaces and minimizing such deposits. In a preferred embodiment, the process of the invention can employ an amine salt of a C.sub.12 to C.sub.24 tertiary alkyl amine an amine oxide, or an amine oxide salt, either alone or with a surfactant.Type: GrantFiled: August 24, 1984Date of Patent: December 16, 1986Assignee: Waterscience, Inc.Inventor: Robert J. Littmann
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Patent number: 4617129Abstract: Method of inhibiting the precipitation of calcium carbonate from an aqueous system, comprises adding to the aqueous system a scale precipitation inhibiting amount of bis(phosphonomethylene) aminomethylene carboxylic acid.Typical aqueous systems usefully treated by the new method are water- or oil well systems, cooling water systems, steam generating systems, sea-water evaporators, hydrostatic cookers, gas-scrubbing systems, closed circuit heating systems, reverse-osmosis systems and aqueous-based refrigeration systems.Type: GrantFiled: July 3, 1985Date of Patent: October 14, 1986Assignee: Ciba-GeigyInventor: Michael J. Lees
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Patent number: 4599217Abstract: Apparatus for determining the corrosion rate of industrial condensing equipment so that corrosion inhibitors may be effectively utilized to control corrosion. The apparatus which simulates a cooling circuit for process streams which require the introduction of reagents to inhibit corrosion includes a primary condenser with automatic cooling control and more than one serially connected cooling-monitoring section, associated means for monitoring corrosion rate, temperature, and/or dewpoint and means for adjustibly controlling the process stream cooling rate of said cooling-monitoring sections. The process stream is flowed through said serial connected cooling-monitoring sections in order to cool the vapors in a manner which simulates cooling that will take place in a parallel connected heat exchanger unit.Type: GrantFiled: January 22, 1985Date of Patent: July 8, 1986Assignee: Exxon Chemical Patents Inc.Inventors: William G. Winston, David M. Groves
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Patent number: 4566973Abstract: In a preferred embodiment, this invention relates to a method for inhibiting formation of phosphate scale in water systems by the addition of a threshold amount of a water-soluble copolymer of 40 to 95 weight parts of an acrylic acid with 5 to 60 parts of a substituted acrylamide, based on a total of 100 parts of polymerized monomers.Type: GrantFiled: August 6, 1984Date of Patent: January 28, 1986Assignee: The B. F. Goodrich CompanyInventors: William F. Masler, III, Zahid Amjad
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Patent number: 4563284Abstract: This invention is directed to the method of dispersing inorganic matter and to scale inhibition in an aqueous system by addition thereto of an effective amount to obtain synergistic threshold inhibition of a phosphonocarboxylic acid and a polymeric phosphinocarboxylic acid, the phosphonocarboxylic acid being a phosphonoalkane carboxylic acid containing preferably two phosphono groups, 2 to 4 carbon atoms in the alkane hydrocarbon group, and three carboxylic acid groups; and the polymeric phosphinocarboxylic acid contains features of both phosphonates and polyacrylates.Type: GrantFiled: August 6, 1984Date of Patent: January 7, 1986Assignee: The B. F. Goodrich CompanyInventor: Zahid Amjad
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Patent number: 4508683Abstract: The concentration of cyanides in the sour water system of FCC reactor is controlled by injecting such an amount of ammonium polysulfide (APS) into the system that the weight ratio of net free sulfur to simple cyanides in the sour water is about 0.6 to about 3.8. The pH of the sour water is at least 8.0.Type: GrantFiled: November 10, 1983Date of Patent: April 2, 1985Inventors: Brian E. Doll, Patrick G. Smyth
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Patent number: 4497702Abstract: A hydrocarbonaceous liquid stream is modified to contain a minor amount of the amide reaction product of a polyalkylene polyamine and a neo-acid having 5 to 20 carbon atoms, the neo-acid having three alkyl groups on the carbon atom which is in the alpha position relative to the carboxylic group, whereby corrosion of iron and other metals contacted by said stream is significantly reduced.Type: GrantFiled: August 9, 1982Date of Patent: February 5, 1985Assignee: Atlantic Richfield CompanyInventors: Richard F. Miller, Tony S. Go, George R. Wilson, III