Heavy Metal Patents (Class 210/912)

Cross-Reference Art Collections

Chromium (Class 210/913)
  • Patent number: 5651895
    Abstract: The present invention in one embodiment, is a process that uses a chemical treatment to remove heavy metals from wastewater; heavy metals from wastewater containing oxygenated hydrocarbons; and arsenic, organic acids, and heavy metals from antifreeze solutions. In one aspect such a method includes adding an iron salt, to an antifreeze solution containing arsenic and heavy metals with adequate mixing for dispersion throughout the solution. Then, a base is added to increase the pH to a level from about 8 to 10. As the base is added, a precipitate with contaminates forms and is then removed by standard filtration techniques. The arsenic, organic acids, and heavy metals co-precipitate with the iron and are removed by filtration. The process may either be a batch process or a continuous process. In one aspect the wastewater is generated by a process according to the present invention for purifying contaminated soil or sediment.
    Type: Grant
    Filed: December 11, 1995
    Date of Patent: July 29, 1997
    Assignee: Envirocorp Services & Technology
    Inventor: Ronnie D. Gordon
  • Patent number: 5645730
    Abstract: A process for treating acid wastewater containing heavy metals has been invented, the process including adding fly ash to the acid wastewater to reduce heavy metals content of the acid wastewater. In one aspect the acid wastewater contains soluble iron and adding fly ash reduces the level of soluble iron. In one aspect the acid wastewater contains sulfate ions and adding fly ash reduces the sulfate ion level. In one aspect solid silicate salts are added to the acid wastewater. Preferably undesirable very hydrous iron hydroxide precipitate is not formed. In certain aspects the pH of the acid wastewater is raised to an environmentally acceptable level. In one aspect the process is a batch process. In another aspect the process is a continuous process.
    Type: Grant
    Filed: April 29, 1996
    Date of Patent: July 8, 1997
    Assignee: Envirocorp Services & Technology, Inc.
    Inventors: Edward Malachosky, Ronnie D. Gordon
  • Patent number: 5639347
    Abstract: A method and apparatus facilitate removal of metals from acidic liquids containing dissolved metals (such as pulp mill bleach plant washer filtrate) by oxidizing the liquid with ozone, hydrogen peroxide, oxygen, and/or air to increase the valence of the metals (like Mn and Fe) so that they become easier to precipitate. Oxidation may be practiced using any suitable reactor, such as a gas-contact reactor, or a plunger type reactor where the oxidizing agent is primarily gaseous, or a static mixer or stirred tank where the oxidizing agent is primarily liquid. After oxidation the pH of the liquid is adjusted (e.g. to over 6, preferably about 8-11) to precipitate the metals. The precipitated metals are then removed by filtration, sedimentation or flotation, and the metals-depleted liquid used elsewhere in the pulp mill.
    Type: Grant
    Filed: August 31, 1993
    Date of Patent: June 17, 1997
    Assignee: Ahlstrom Machinery Inc.
    Inventor: Hans G. Lindberg
  • Patent number: 5639383
    Abstract: This procedure includes detecting and rejecting the used mineral motor oils containing polychlorinated biphenyls (PCB's) and/or polychlorinated triphenyls (PCT's) before filtering; before the decantation and/or distillation step, if necessary, submitting the used mineral motor oil to thermal shock treatment. In the recycling process, stabilizing the used mineral motor oils that normally contain heavy metals by adding to bitumen, using 0 to 15 percent of used mineral motor oil and a minimum of 85 percent bitumen for bituminous pavements and 1 to 20 percent of used mineral motor oils and a minimum of 80 percent bitumen for bitumen emulsions and paints. Also in the recycling process the used mineral motor oils are mixed with bitumen and paraffinic elastomers, stabilizing the heavy metals contained in the used mineral motor oils, getting usual bituminous pavements, self-draining bituminous pavements, sport pavements, etc. EPM EPDM or butyl rubber are used as paraffinic elastomers.
    Type: Grant
    Filed: April 21, 1994
    Date of Patent: June 17, 1997
    Assignee: Ralfer, S.L.
    Inventors: Carlos Gajas Fuertes, Miguel Balada Subirats
  • Patent number: 5637232
    Abstract: A improved process is provided for the catalytic oxidation of ferrous iron in liquid media in the presence of oxygen. The improvement is provided by the use of a carbonaceous char catalytically active for said oxidation which is prepared by the carbonization and oxidation of a bituminous coal or a bituminous material at temperatures below 700.degree. C. followed by exposure of the carbonized, oxidized char to a nitrogen-containing compound and, during or after said exposure, increasing the temperature to at least 700.degree. C.
    Type: Grant
    Filed: March 11, 1996
    Date of Patent: June 10, 1997
    Assignee: Calgon Carbon Corporation
    Inventor: Richard A. Hayden
  • Patent number: 5637228
    Abstract: This invention relates to methods, systems and apparatus for producing primary treated brine, i.e. <20 ppm calcium, magnesium, strontium and barium ions at the wellhead of underground salt caverns formed by depletion of their salt content by previous solution mining operations. The purified brine produced is maintained in an anerobic state and transported to chlor-alkali plant installations for use in electrolysis cells for the production of chlorine, sodium hydroxide and hydrogen. Raw brine produced at an operating brine wellhead is injected into a depleted salt cavern along with the treatment chemicals required to purify the raw brine. A novel installation including a producing well or wells, a depleted well cavern or caverns, and support facilities for producing primary treated brine is provided.
    Type: Grant
    Filed: January 3, 1995
    Date of Patent: June 10, 1997
    Assignee: Texas Brine Corporation
    Inventors: Lawrence F. Becnel, Jr., Thomas M. Ellis
  • Patent number: 5637210
    Abstract: A treatment zone 10 in the form of a basin 12 having an inlet port 14 and an outlet port 16. The inlet port 14 allows water to flow into the basin 12. The outlet port 16 allows water to flow out of the basin 12. The inlet port 14 and the outlet port 16 are located at opposite ends of the basin 12 so as to allow water from a body of water having a concentration of water soluble metal ions contained therein to flow substantially through the entirety of the basin 12. A porous matrix 22 is disposed within the treatment zone 10. The porous matrix 22 is inoculated with a population of aerobic metal oxidizing bacteria. The population of aerobic metal oxidizing bacteria is capable of metabolizing water soluble metal ions in the water from the body of water into water insoluble metal oxides. Thus, there is an overall decrease in the concentration of the metal ions in the water flowing out of the treatment zone 10 as compared to water flowing into the treatment zone 10.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: June 10, 1997
    Inventors: William J. Vail, Robert K. Riley
  • Patent number: 5637355
    Abstract: The present invention involves a method of removing paint containing heavy metal from a surface without the production of hazardous wastes. Specifically, this method involves applying a coating preparation to the heavy metal containing paint prior to its removal from its surface. The preparation contains lead reactive chemicals such as phosphates, metal sulfides and organic sulfides. The preparation may also contain buffers such as magnesium oxide and magnesium hydroxide. These chemicals react with the heavy metals rendering them nonhazardous. The invention also involves the coating preparation itself.
    Type: Grant
    Filed: April 22, 1996
    Date of Patent: June 10, 1997
    Assignee: RMT, Inc.
    Inventors: Robert R. Stanforth, Paul V. Knopp
  • Patent number: 5635073
    Abstract: A method for the removal of metal from a metal-containing aqueous medium wherein the aqueous medium is passed through a particulate carrier material in the presence or ferrous iron and an oxidant and at such velocity and in such direction that the carrier material particles are fluidised in the aqueous medium and wherein metal-containing coatings are formed on the surfaces of the carrier material particles and wherein the particles thus coated are separated from the aqueous medium. A method for the production of iron oxyhydroxide-containing adsorbent wherein the carrier material particles are fluidised in an aqueous medium in the presence ferrous iron and an oxidant so as to form iron oxyhydroxide coatings on the particles and wherein the particles thus formed are separated from the aqueous medium.
    Type: Grant
    Filed: April 12, 1995
    Date of Patent: June 3, 1997
    Assignee: Kruger AS
    Inventors: Henrik Aktor, Terkel C. Christensen
  • Patent number: 5632900
    Abstract: A method for treating a chelate bearing waste solution employs a two-step process which includes elevating the pH of the solution to a pH greater than 10 and precipitating the metal as the hydroxide out of solution, followed by treating the resultant solution with an oxidant to destroy any remaining free chelate.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: May 27, 1997
    Assignee: The Babcock & Wilcox Company
    Inventors: John M. Jevec, Carl J. Lenore
  • Patent number: 5632901
    Abstract: The present invention relates to a process for the elimination of heavy metals from a closed white water system within the pulp and paper industry, wherein one adjusts the pH of the white water to between 5 and 11, and that one subsequently precipitates the resins present using a flocculation agent, whereby by a simultaneous elimination of the heavy metals is obtained.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: May 27, 1997
    Assignee: Kemira Kemi Aktiebolag
    Inventor: Bengt T. Engstr om
  • Patent number: 5622631
    Abstract: Apparatus combination and system for reducing use of fresh water in a photoprocessing operation by recirculation of the wash water to the photoprocessing operation via a silver recovery system. Wash water is periodically discharged to waste and a like amount of fresh water is added to the system which serves to reduce the concentration of thiosulfate ions in the wash water.
    Type: Grant
    Filed: August 7, 1995
    Date of Patent: April 22, 1997
    Inventor: Gerson J. Rosenfield
  • Patent number: 5618439
    Abstract: A method for purifying aqueous solutions having varying concentrations of contaminants and/or various contaminants including ions of several metals and elements by conducting precipitation in a first precipitation stage by adding lime in a surplus quantity whereby a pH of about 12 is established and maintained in the solution and a major part of the contaminant content is precipitated so as to form a solution having a substantially constant composition and to form a precipitate that is isolated and removed together with residual lime. Precipitation is then conducted in a second precipitation stage by adding a reagent for precipitation at a pH in the range of 4-11 wherein residual contaminant in the formed solution from the first precipitation stage is precipitated the precipitate is isolated and returned to the first precipitation stage.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: April 8, 1997
    Assignee: Boliden Contech AB
    Inventor: Torkel Allgulin
  • Patent number: 5616251
    Abstract: The present invention is directed to the use of water-soluble compositions containing a compound having a Lewis base group attached to a hydrophobic group where the Lewis base group is capable of donating at least one lone pair of electrons to a metal. These compositions are effective in treating acid mine drainage by treating the source of the acid mine drainage as well as the acid mine drainage waters. These compositions are also effective in removing metal and non-metal ions from aqueous sources and the process can be modified to allow the selective removal of metal and non-metal ions from aqueous sources.
    Type: Grant
    Filed: November 20, 1995
    Date of Patent: April 1, 1997
    Assignees: Kareem Batarseh, Farid N. Ghadry
    Inventor: Kareem I. Batarseh
  • Patent number: 5616243
    Abstract: A filter basket and filtration media for an inverted bottle type water dispenser which is disposed below the inverted bottle, depending from the collar of the water reservoir into the water reservoir and receiving the neck of the bottle, so that all the water discharged from the bottle passes through the filter basket in a downward direction. The filter basket has an inverted conical upper section which funnels all the water which is drained from the bottle to a filtration compartment at its lower section. The filtration compartment remains submerged in water. The filtration compartment contains the filtration media and discharges the filtered water therefrom directly into the water reservoir. Air released in the spigot when it is opened rises upwardly through the filtration media to be received in the bottle. The filtration media comprises an aluminosilicate gel with pore sizes in the range of sixty to two hundred and fifty Angstroms which provides for rapid flow of water and air therethrough.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: April 1, 1997
    Inventor: Ehud Levy
  • Patent number: 5607596
    Abstract: Process for the treatment of the combustion residues and for the purification of the combustion fumes, in which the residues are washed and then rinsed to reduce the leachable fraction both in respect of the trace elements and in respect of the total soluble fraction, with a low consumption of water and of optional reactants.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: March 4, 1997
    Assignee: Lab S.A.
    Inventor: Jean-Francois Vicard
  • Patent number: 5605632
    Abstract: A silver recovery device (30) is described for removing silver from a silver-containing solution. The device (30) comprises an ion-exchange resin bed (34) and a pump (62) for directing the solution through the resin bed (34). The pump (62) is positioned downstream of the resin bed (34) and the resin bed (34) is held within a retaining space (36) of variable dimensions. Higher liquid flow rates are thereby achievable, without fluidization of the resin.
    Type: Grant
    Filed: August 21, 1995
    Date of Patent: February 25, 1997
    Assignee: Agfa-Gevaert N.V.
    Inventors: Benedictus Jansen, Frank Michiels, Werner Van de Wynckel
  • Patent number: 5605633
    Abstract: A process for treating a photographic waste liquid containing a used processing liquid resulting from a processing step having a bleaching ability or a fixing ability in the processing of a silver halide photographic material which process comprises adding a polymer-complex-forming agent to the waste liquid in an amount in the range of from 0.5 to 4 equivalents to a metal contained in the waste liquid to thereby form a polymer-metal complex and then filtering off the polymer-metal complex with a mono-membrane filter having a pore size of 0.05 to 10 .mu.m to thereby remove the metal. A device for use in practicing the process is also disclosed.
    Type: Grant
    Filed: November 29, 1994
    Date of Patent: February 25, 1997
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takashi Nakamura, Koji Matsuo, Masaharu Yamada
  • Patent number: 5599458
    Abstract: Method to prevent the exhaustion of acid copper plating baths (12) and to treat sewage or sludges (20) containing copper in an ionic form so as to recover metallic copper (39), the method including the addition (11) of a compound which keeps the concentration of iron below a critical value (for instance, 60 grs/lt. ), the compound causing precipitation of iron in the form of ferrous sulphate and thus preventing the co-deposition of crystals of ferrous sulphate and copper sulphate with a possible incorporation of organic impurities such as stearates (35) present in the acid copper plating baths (12).
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: February 4, 1997
    Assignee: Laboratori Taboga di Taboga Leandro
    Inventor: Leandro Taboga
  • Patent number: 5597484
    Abstract: Removal of a target metal having an insoluble phosphate (e.g. actinides), is effected by passing the solution through a bioreactor containing an immobilised phosphatase-producing microorganism which has been cultivated using a culture medium containing an assimilable organic source of phosphorus and which has been primed with an element, other than the metal to be removed, having an insoluble phosphate so as to deposit the phosphate of the priming element on cell surfaces of the microorganism. The priming element phosphate facilitates deposition of the target metal phosphate.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: January 28, 1997
    Assignee: British Nuclear Fuels plc
    Inventors: Mark R. Tolley, Lynne E. Macaskie
  • Patent number: 5594096
    Abstract: A contaminant precipitating composition and method are disclosed. The composition comprises a water soluble branched polymeric composition effective for the purpose of precipitating contaminants from an aqueous solution. The method comprises adding an amount of the composition, effective for the purpose, to the aqueous solution so as to complex, precipitate and remove contaminants from the aqueous solution.
    Type: Grant
    Filed: March 1, 1996
    Date of Patent: January 14, 1997
    Assignee: BetzDearborn Inc.
    Inventors: William S. Carey, Ellen M. Meyer, Jeffrey H. Peltier
  • Patent number: 5587088
    Abstract: A process for the precipitation and separation of inorganic species form aqueous solutions. The method comprises the step of adding a miscible organic solvent to inorganic-aqueous solution so that a solid precipitate from the aqueous solution is formed. The resultant solid precipitate is separated from the organic-water mixture. After separating the solid precipitate, the miscible organic solvent is removed and recovered from the organic-water mixture by applying vacuum or other means of recovery. The separated miscible organic solvent can then be condensed and returned to the process. The water is stripped of traces of miscible organic solvent and removed from the system as product water.
    Type: Grant
    Filed: August 1, 1995
    Date of Patent: December 24, 1996
    Inventor: Mansour S. Bader
  • Patent number: 5575919
    Abstract: Arsenic and TOC are removed from drinking water or wastewaters by use of finely-divided metallic iron in the presence of powdered elemental sulfur or other sulfur compounds such as manganese sulfide, followed by an oxidation step. A premix may be produced for this process, by adding the iron, sulfur and oxidizing agent to water in a predetermined pH range. The iron and sulfur are mixed for a period of time dependent upon the temperature and pH of the water and the presence of complexing or sequestering minerals and organic acids in the water. An oxidizing agent is added to the mixture and agitating is continued. In a preferred embodiment the oxidizing agent is hydrogen peroxide. Water is decanted from the mixture after a sufficient reaction time, to produce a concentrated premix. This premix can be added to water intended for drinking or to industrial effluents containing toxic materials.
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: November 19, 1996
    Assignee: Peter F. Santina
    Inventor: Peter F. Santina
  • Patent number: 5575915
    Abstract: A method of removing silver from a solution containing silver halide and silver ion is described, which comprises a step of adding an a sulfur atom-containing hydrophilic polymer chelating agent to the solution.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: November 19, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takashi Nakamura, Yasuhiro Nakayama, Haruhiko Iwano, Hideo Miyazaki
  • Patent number: 5573676
    Abstract: Process for the decontamination of decontaminants in waste waters, wherein the waste water stream to be treated pass sequentially through following process steps,waste water treatment with hydrogen peroxide (H.sub.2 O.sub.2), irradiating at the same time with UV light,treatment with a reducing agent such as sodium dithionite,precipitation of existing metal contaminants, optionally followed by a filtration and/or a treatment with a selective ion exchanger.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: November 12, 1996
    Assignee: Ultra Systems GmbH UV-Oxidation
    Inventors: Karl F. Massholder, Wilfried Werz, Erwin Ecker
  • Patent number: 5569386
    Abstract: A method for controlling the detoxification of aqueous solutions containing cyanides and/or cyano complexes, in particular zinc cyano complexes, with the use of a source for formaldehyde for glycolnitrile formation and a source for hydrogen peroxide for perhydrolysis of the glycolnitrile is disclosed. During the addition of the source for formaldehyde at a pH value in the range from 8.5 to 12 the pH value is kept constant by addition of an acid. The addition of the source for formaldehyde is discontinued if the pH value no longer increases.
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: October 29, 1996
    Assignee: Degussa Aktiengesellschaft
    Inventor: Hubert Wolf
  • Patent number: 5558775
    Abstract: There is disclosed a portable assembly for treating hazardous waste water having a plurality of paired filter units having filter mediums and operated at high filter rates to minimize solids build up wherein solids are caused to be smashed and broken by shear forces and wherein chemicals are sequentially added to facilitate solids reduction, to oxidize organic compounds and to precipitate dissolved solids and wherein the process stream is subjected to ultraviolet light to reduce organic loading and downstream ultra filtration units to further reduce solids followed by reverse osmosis and/or ionization treatment.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: September 24, 1996
    Assignees: Joseph Busch, Jr., Joseph Busch, Sr.
    Inventor: Joseph B. Busch, Jr.
  • Patent number: 5554355
    Abstract: A method and apparatus for forming a slurry of metal oxide in a mineral or the like (e.g. of magnesium or calcium oxide) and introducing the slurry to an acid neutralization process in a time period before substantial hydration of the oxide has occurred.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: September 10, 1996
    Assignee: PSC Technologies, Inc.
    Inventor: Thomas Miller
  • Patent number: 5554290
    Abstract: An insitu method and system for removing dissolved heavy metals and nitrates from groundwater is disclosed. The invention comprises the formation of insitu anaerobic reactive zones to precipitate and filter out dissolved heavy metals as metallic sulfides and to degrade nitrate to nitrogen gas. The invention is comprised of an injection well or wells into a saturated zone that contains dissolved heavy metals or nitrate contaminated groundwater. A conduit, located within the injection well, pumps carbohydrates in the case of nitrates, into the contaminated groundwater. Indigenous microbes digest the carbohydrates, producing an anaerobic condition within the reactive zones. In the presence of sulfates, the sulfates are reduced to sulfide ions. The sulfides readily combine with the dissolved heavy metal ions and form insoluble precipitates. The resultant precipitates are filtered out by the soil matrix within and down gradient of the reactive zones.
    Type: Grant
    Filed: April 11, 1995
    Date of Patent: September 10, 1996
    Assignee: Geraghty & Miller, Inc.
    Inventor: Suthan S. Suthersan
  • Patent number: 5547583
    Abstract: Metals and organics are extracted from solution by co-precipitating them with a gel comprising aluminum hydroxide and a complexing agent such as EDTA. After the gel is processed to remove the metals and organics, it can be recycled for further use by dissolving it in a high-pH solution, leaving no secondary waste stream. A number of alternative complexing agents perform better than EDTA.
    Type: Grant
    Filed: November 30, 1994
    Date of Patent: August 20, 1996
    Inventor: Donald H. Alexander
  • Patent number: 5547588
    Abstract: A process for treatment of hazardous liquid waste comprising trace amounts of hazardous elements in solution as oxyanions by oxyanion fixation within ettringite and related minerals. In accordance with the disclosed process, reagents for forming ettringites are mixed with the waste stream resulting in the formation of oxyanion-substituted ettringite and related materials. The resulting ettringite and related minerals are separated by filtration from the liquid. Thereafter, the liquid, having an elevated pH, is neutralized by carbon dioxide sparging resulting in precipitation of excess reagents in the liquid. Thereafter, the precipitates are filtered, producing a clean liquid.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: August 20, 1996
    Assignee: Gas Research Institute
    Inventors: David J. Hassett, Jeffrey S. Thompson
  • Patent number: 5545331
    Abstract: Heavy metal ions react with iron particles in acidic aqueous solution to form heavy metallic particles that are suitable for recycling and reuse when recovered from the aqueous solution. Chelating agents that are present are deactivated by bonding to ferrous ions produced from the iron particles. An alkali metal hydroxide is utilized to precipitate remaining heavy metal ions including ferrous and ferric ions which are recycled to the acidic aqueous solution.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: August 13, 1996
    Assignee: Romar Technologies, Inc.
    Inventor: Robert G. Guess
  • Patent number: 5538645
    Abstract: A process for the removal of species containing metallic ions from effluents by yeast cell walls. The yeasts used are selected from Saccharomyces cerevisae, Saccharomyces uvarum and Saccharomyces lipolytica. According to the process, the washed yeast cell walls are first treated by a water soluble aldehyde and after sorbing the metallic ions, the yeast cell walls may regenerated by a mineral acid or a chelate solution such as ethylene-diamine tetraacetic acid, releasing the sorbed metal ions. According to a preferred embodiment, water containing acetone or alcohol is used for washing the yeast cell walls. The sorption by the yeast cell walls is carried out at a pH in the range of 1 to 13 and preferably in the range of 4 to 7. The most preferred aldehyde is selected from formaldehyde and glutaraldehyde or any mixture thereof. The metal sorption process may be carried out batchwise or continuously. In the continuous process, the yeast cell walls are immobilized on porous glass, purified sand or polymers.
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: July 23, 1996
    Assignee: Technion Research & Development Foundation Ltd.
    Inventors: Shmuel Yannai, Galit Meshulam
  • Patent number: 5536416
    Abstract: The present invention is a method to remove metals from solutions by precipitating the metals and adding cellulosic fiber to the solution. The precipitates attach to the cellulosic fibers to form products. The products may be removed from the solution by gravity separation techniques or by filtration. The removed products may be dewatered and incinerated. The method provides a simple and effective technique for removing low concentrations of metals from high volume solution streams.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: July 16, 1996
    Assignee: Hazen Research, Inc.
    Inventors: Enzo Coltrinari, Wayne C. Hazen
  • Patent number: 5531906
    Abstract: A process for treating sodium hydroxide waste liquor containing aluminum, comprising the steps of: adding, to aluminum-containing sodium hydroxide waste liquor, at least one of MgO and Mg(OH).sub.2 in an amount of 0.5 to 3 moles with respect to 1 mole of aluminum to cause a reaction at 70.degree. C. or more; and separating and removing a precipitated magnesium-aluminum compound is disclosed. The present invention makes it possible to recover recyclable sodium hydroxide from an aluminum-containing sodium hydroxide waste liquor. Even if the recovering procedure is repeated, no carbonate ions are accumulated. Therefore, it is possible to prevent degradation of the treating solution containing sodium hydroxide. Further, the by-product is a useful compound, and thus, there is no problem in the reprocessing or disposal of the by-product.
    Type: Grant
    Filed: August 1, 1994
    Date of Patent: July 2, 1996
    Assignee: Nittetsu Mining Co., Ltd.
    Inventors: Susumu Takayama, Yasuie Mikami, Nobuyoshi Iyatomi, Minoru Orikasa
  • Patent number: 5522996
    Abstract: The invention disclosed relates to an agent capable of selectively binding lithium ions to form a lithium complex, employed in association with a biologically inert carrier or excipient. Typically, the agent is included in a novel graft polymer, such as a cross-linked polystyrene polymer. This invention may also be applied to sensing lithium ion concentrations in aqueous solution and to the selective removal of lithium ions from an aqueous solution, including biological fluids.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: June 4, 1996
    Assignee: National Research Council of Canada
    Inventors: Sydney K. Brownstein, Pierre-Yves Plouffe
  • Patent number: 5523002
    Abstract: A contaminant precipitating composition and method are disclosed. The composition comprises a water soluble branched polymeric composition effective for the purpose of precipitating contaminants from an aqueous solution. The method comprises adding an amount of the composition, effective for the purpose, to the aqueous solution so as to complex, precipitate and remove contaminants from the aqueous solution.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: June 4, 1996
    Assignee: Betz Laboratories, Inc.
    Inventors: William S. Carey, Ellen M. Meyer, Jeffrey H. Peltier
  • Patent number: 5520811
    Abstract: Metals have phosphates of low water solubility e.g. Cd, Pb, Cu, Mn, Sr, U, La, Pu, Am and Np, are removed from water by reaction with phosphate produced by enzymatically-cleaved polyphosphate which has been accumulated by one or more polyphosphate-accumulating microorganisms.
    Type: Grant
    Filed: June 28, 1995
    Date of Patent: May 28, 1996
    Assignee: British Nuclear Fuels PLC
    Inventors: Rosemary E. Dick, Lynne E. Macaskie
  • Patent number: 5518637
    Abstract: A concentrator for reducing the volume of a mixture containing a solvent and various dissolved and/or undissolved solids includes means forming a chamber adapted to receive the mixture and means coupled to the chamber for applying heat to the mixture within the chamber, the heat being provided at a temperature sufficient to vaporize the solvent. A condensing tower receives the vapors from the chamber and including a first stage and at least one second stage. A plurality of walls included in each of the first stage and the second stage of the tower direct the vapors along a torturous path including at least one reversal of direction in each of the stages. A coolant is provided to cool the second stage of the tower but not the first stage in order to facilitate condensation of the vapors in the second stage but not in the first stage of the tower. The coolant may include water in order to facilitate the processing of aqueous solutions.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 21, 1996
    Assignee: Eco Still, Inc.
    Inventor: Henry S. Myers
  • Patent number: 5518633
    Abstract: Process for treating aqueous media containing metal ions having valences of +2 and higher and optionally acid comprising:(a) contacting the aqueous media, at a pH of about 1-5, with an effective amount of product recycled from step (b) to dissolve at least some metal carbonates, produce at least some CO.sub.2, convert at least some metal ions having a valence of at least +3 to metal hydroxide precipitates, and neutralize some acid, if present;(b) contacting the product of step (a), at a pH of about 4-8.5, with an effective amount of Na.sub.2 CO.sub.3 to convert at least some metal ions of +2 valence to metal carbonate precipitates and form at least some dissolved sodium salts;(c) recovering, from a portion of the product from step (b) that is not recycled, metal carbonates, metal hydroxides, and sodium salts.
    Type: Grant
    Filed: October 21, 1994
    Date of Patent: May 21, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Cary V. Brown, John S. Craven, Gregory A. Martz, James E. Merkle, Jr., William L. Vick, Melissa C. Wagner
  • Patent number: 5512257
    Abstract: Fly ash from incineration plants is treated with an acidic aqueous solution for the purpose of removing heavy metals. The residual solid matter is filtered. The filtration residue is treated with a precipitating agent for heavy metals. The thereby obtained inert residue can be directly dumped.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: April 30, 1996
    Assignee: Von Roll Umwelttechnik AG
    Inventor: Rudolf Frey
  • Patent number: 5510040
    Abstract: Selenium compounds present in aqueous liquids can be removed using a poly dithiocarbamate materials. The selenium compounds are then removed by precipitation or sedimentation. Optionally, an oxidizing agent may be added to the system prior to the addition of the poly dithiocarbamate. Various filtration methods may be employed to remove the selenium-dithiocarbamate materials from aqueous liquids.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: April 23, 1996
    Assignee: Nalco Chemical Company
    Inventors: Thomas M. Miller, Walter H. Goodman
  • Patent number: 5509999
    Abstract: The removal of bleaching chemical-consuming metals from treatment fluids in a cellulose pulp mill is facilitated by treating the pulp in an acidic or neutral stage to dissolve metals, washing or thickening the pulp to produce a filtrate containing dissolved metals, and then using an alkali liquid to adjust the pH of the filtrate to cause dissolved metals to precipitate. The alkali liquid is pretreated with carbon dioxide to reduce the sulfide content and increase the carbonate content thereof, preferred alkali liquids being green liquor and white liquor. The reduced-metal content filtrate is used in the bleach plant of the pulp mill, to make bleaching chemicals, as a wash liquid, etc. Treatment of the alkali liquid with carbon dioxide is typically practiced by scrubbing the liquor with carbon dioxide gas, for example, using a plate column scrubber or a stationary packing scrubber.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: April 23, 1996
    Assignee: Kamyr, Inc.
    Inventor: Hans G. Lindberg
  • Patent number: 5510032
    Abstract: A treatment zone 10 in the form of a basin 12 having an inlet port 14 and an outlet port 16. The inlet port 14 allows water to flow into the basin 12. The outlet port 16 allows water to flow out of the basin 12. The inlet port 14 and the outlet port 16 are located at opposite ends of the basin 12 so as to allow water from a body of water having a concentration of water soluble metal ions contained therein to flow substantially through the entirety of the basin 12. A porous matrix 22 is disposed within the treatment zone 10. The porous matrix 22 is inoculated with a population of aerobic metal oxidizing bacteria. The population of aerobic metal oxidizing bacteria is capable of metabolizing water soluble metal ions in the water from the body of water into water insoluble metal oxides. Thus, there is an overall decrease in the concentration of the metal ions in the water flowing out of the treatment zone 10 as compared to water flowing into the treatment zone 10.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: April 23, 1996
    Inventors: William J. Vail, Robert K. Riley
  • Patent number: 5505857
    Abstract: Metals contained in various wastewaters are selectively recovered as metal precipitates and/or as spinel ferrite and water suitable for discharge into the environment is obtained. High grade magnetic spinel ferrite is recovered from wastewaters having aluminum and arsenic if present in the wastewater, removed from the wastewater. There are three process stages for the treatment of wastewater. In the first process stage which is optional, at least a portion of at least one non-ferrous or non-ferric metal is precipitated from the wastewater by subjecting the wastewater to an oxidizing agent to increase the oxidation-reduction potential of the water, by adjusting the pH of the wastewater to a pH at which the metal precipitates from the water and by adding an organic or inorganic sulfur compound, capable of causing the metal to form a precipitate, to the water in a quantity sufficient to precipitate the metal.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: April 9, 1996
    Assignees: Buckman Laboratories International, Inc., Board of Regents of the University and Community College System of Nevada on behalf of the University of Nevada
    Inventors: Manoranjan Misra, Mark E. Kravetz, Kang Yang, Thomas E. McNeel
  • Patent number: 5500125
    Abstract: A method of treating photoprocessing wash water, comprising in sequence, the steps of:A) contacting the wash water with an acrylic anion exchange resin to remove silver thiosulfate complex in the water; andB) contacting the water from step A) with an oxidizing agent that converts thiosulfate ions to sulfate ions.C) recirculating continuously through the photoprocessing wash tank and steps A) and B).
    Type: Grant
    Filed: May 19, 1994
    Date of Patent: March 19, 1996
    Assignee: Eastman Kodak Company
    Inventors: Richard R. Horn, Christine K. Gaskell, Susan R. Krauss, Michael D. Purol
  • Patent number: 5500133
    Abstract: A contaminant precipitating composition and method are disclosed. The composition comprises a water soluble, branched, polydithiocarbamic acid salt effective for the purpose of precipitating contaminants from an aqueous solution. The method comprises adding an amount of the composition effective for the purpose to the aqueous solution so as to complex, precipitate and remove contaminants from the aqueous solution.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: March 19, 1996
    Assignee: Betz Laboratories, Inc.
    Inventors: William S. Carey, Ellen M. Meyer
  • Patent number: 5500131
    Abstract: Materials and methods relating to water treatment processes are described. More specifically, the process is non-toxic and is useful for the removal of algae, other suspended solids, or contaminants in surface waters or in potable water treatment. Coccolithic calcium carbonate can be used in combination with a flocculent such as aluminum chloride to obtain the desired results.
    Type: Grant
    Filed: April 5, 1994
    Date of Patent: March 19, 1996
    Inventor: Jean-Paul Metz
  • Patent number: 5496474
    Abstract: A process for inhibiting the formation of an unwanted precipitate comprising [H.sub.2-n TMT]Na.sub.n [HNR.sub.3 ] during the precipitation of silver mercapto-s-triazine (AgTMT) from a silver containing photoprocessing solution, comprising the steps of:(a) providing a base solution;(b) providing a reagent solution containing mercapto-s-triazine (TMT), or a water soluble salt thereof;(c) mixing the TMT reagent solution with the photoprocessing solution; and(d) adding sufficent base to increase the pH of the mixture of the TMT reagent and photoprocessing solutions above the pH of the mixture before addition of base, and the base is mixed:(i) directly to the photoprocessing solution before mixing TMT reagent with the photoprocessing solution; or(ii) with the photoprocessing solution concurrently with TMT reagent; or(iii) immediately after the point TMT reagent begins mixing with the photoprocessing solution.
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: March 5, 1996
    Assignee: Eastman Kodak Company
    Inventors: Charles S. Christ, Jr., Albert R. Szembrot
  • Patent number: H1661
    Abstract: A process for removing complexed or chelated ions from an aqueous solution using a cationic chelating resin in the sodium form. The process is particularly useful for removing metal ions chelated during a metal plating process with specific utility for recovering cadmium from a cadmium cyanide complex.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: July 1, 1997
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Jennie L. Koff, Daniel A. Zarate