Sulfuric Acid Patents (Class 71/40)
  • Patent number: 9422202
    Abstract: The present invention relates to an amorphous, vitreous phosphorus-potassium fertilizer obtained by melting raw materials containing phosphorus pentoxide (P2O5), potassium oxide (K2O), providers of SiO2 and silicates, and providers of MgO and CaO. The fertilizer of the present invention is produced by a process of melting the raw materials, followed by quenching, enabling the formation of a vitreous and amorphous material containing phases of phosphorus and of potassium, which are soluble in a weak acid.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: August 23, 2016
    Assignee: Mineracao Curimbaba Ltda.
    Inventors: Minoru Yasuda, Gabriel Warwick Kerr de Paiva Cortes
  • Publication number: 20140123718
    Abstract: A fertilizer is obtained from defluorinated phosphate rock, previously treated in an acidic medium, with the particularity of being almost entirely available and assimilable, ensuring that phosphorus is kept soluble in the soil substrate so that it can be entirely assimilated by plants. It responds to the following reaction: HnPO4Xm+SO4?2?HnPO4?m+SO4?2+NH4+H2O, which at a density of from 1.25 to 1.30, and pH 1.8-2.6, becomes almost entirely available to and assimilable by plants, and remains soluble in the soil stratum. The process developed for yielding the liquid phosphate fertilizer solution is disclosed.
    Type: Application
    Filed: November 1, 2013
    Publication date: May 8, 2014
    Inventor: José Ramón Florencio Antelo
  • Patent number: 8557013
    Abstract: The invention is directed to processes for treating biosolids that result in high-value, nitrogen-containing, slow-release, organically-augmented inorganic fertilizer that are competitive with less valuable or more costly conventional commercially manufactured fertilizers. The process involves conditioning traditional waste-water biosolids and processing the conditioned biosolids continuously in a high throughput manufacturing facility. The exothermic design and closed loop control of the primary reaction vessel decreases significantly the amount of power necessary to run a manufacturing facility. The process utilizes green technologies to facilitate decreased waste and enhanced air quality standards over traditional processing plants. The fertilizer produced from recovered biosolid waste is safe and meets or exceeds the United States Environment Protection Agency (USEPA) Class A and Exceptional Quality standards and is not subject to restrictions or regulations.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: October 15, 2013
    Assignee: VitAG Holdings, LLC
    Inventors: Jeffrey C. Burnham, James P. Carr, Gary L. Dahms
  • Patent number: 8123116
    Abstract: A system for providing dispensing of fuel for refuelling vehicles, comprising a control unit and at least two switches. Each of said switches is connected to the control unit and comprises a microcontroller for storing a unique identifier, which identifier is associated with the switch and readable by the control unit, for allowing the control unit to identify each of the at least two switches.
    Type: Grant
    Filed: May 21, 2008
    Date of Patent: February 28, 2012
    Assignee: Dresser, Inc.
    Inventors: Christer Lundgren, Per Kristiansson
  • Patent number: 7947104
    Abstract: The invention describes a new method for treating sludge, which can result in the production of high nitrogen organically-augmented inorganic fertilizer that incorporates municipal sludges or biosolids or organic sludges that can compete with traditional fertilizers such as ammonium phosphate, ammonium sulfate and urea on the commodity fertilizer marketplace. The method takes advantage of the thixotropic property of dewatered biosolids or organic sludge to create a pumpable paste-like material from the biosolids or organic sludge that is then treated with an oxidizer to reduce odorant effects and an acid. This mix is then interacted with concentrated sulfuric and or phosphoric acids and an ammonia source or alternatively a hot or molten melt or salt of ammonium sulfate/phosphate to form a fertilizer mix. The present invention controls the heat, atmospheric pressure and retention time of the fertilizer mix in the reaction vessel.
    Type: Grant
    Filed: February 19, 2008
    Date of Patent: May 24, 2011
    Assignee: Vitag Corp.
    Inventors: Jeffrey C. Burnham, James P. Carr, Gary L. Dahms
  • Patent number: 7534281
    Abstract: The invention is directed to a process for enhancing the plant nutrient value of relatively low analysis organic waste material (e.g. sewage sludge) involves treating the waste material with an acid and base in a pipe-cross reactor or tubular to form a melt; spraying the melt onto a recycling bed of fines in a granulator and flashing off the water contained in the melt as steam; rolling the melt onto recycled fine particles in a granulator to form granulated particles; and drying these granulated particles in a to form an enhanced plant nutrient value composition (e.g. a fertilizer or soil conditioner having a greater NPK value than the original relatively low analysis organic waste material). The process further includes drawing off the fumes from the granulator, passing them through a dryer with the granulated particles, and subsequently oxidizing the fumes to eliminate volatile organic compounds and/or gaseous hydrocarbon pollutants be converting such into carbon dioxide and water vapor.
    Type: Grant
    Filed: September 15, 2006
    Date of Patent: May 19, 2009
    Assignee: Environmental Technologies Capital Partners, LLC
    Inventors: Gary L. Dahms, Gary D. Greer
  • Patent number: 7452398
    Abstract: The primary object of the invention is to provide a method of producing novel phosphate and potash (PK) containing compound fertilizers in the form of powders showing good handle-ability by which method the phosphate components contained in an incinerated ash residue of chicken droppings is improved in solubility and thus rendered effective or available and, at the same time, the free CaO-derived alkali is neutralized, as well as such novel phosphate and potash(PK) containing compound fertilizers.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: November 18, 2008
    Assignee: Murakashi Lime Industrial Co., Ltd.
    Inventors: Teruo Urano, Yuya Sato
  • Patent number: 6346131
    Abstract: A plant fertilizer composition that includes an acid whereby said acid may react with, chelate, or block any metal ions in the soil in which the plants grow during administration of the fertilizer. This reaction renders the metal ions substantially ineffective for reacting with the fertilizer components. The fertilizer is thereby shielded from interference with any metal ions in the soil and the delivery of the fertilizer to the plant roots is thereby enhanced. The acid may be, but is not limited to, an organic acid and is preferably citric acid. The fertilizer composition may include phosphorus. Likes in one embodiment, the fertilizer composition may include phosphate ions and citric acid, the citric acid chelating any metal ions in the soil in which the plants grow thereby facilitating the transportation of phosphate to the plant roots.
    Type: Grant
    Filed: November 3, 1999
    Date of Patent: February 12, 2002
    Inventor: David W. Bergevin
  • Patent number: 6231767
    Abstract: A process for treating thickened phosphatic clay suspensions, waste clay and phosphogypsum produced in the processing of phosphate ore by water beneficiation and chemical processing, the thickened phosphatic clay suspension having a solid content of from about 4 to about 40 percent by weight, includes mixing a sufficient amount of deflocculating agent with a thickened phosphatic clay suspension to cause deflocculation of the suspension to an extent sufficient to reduce the viscosity thereof to a value enabling the deflocculated suspension to be readily pumped from one location to another, the deflocculating agent comprising an alkali compound of a phosphorus oxide. The deflocculated suspension of reduced viscosity is pumped from one location to another and separated into a clay suspension and a phosphatic mineral and sand suspension.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: May 15, 2001
    Assignee: Claytech Enviromental Services Inc.
    Inventors: David Krofchak, Roberto Berardi
  • Patent number: 5308372
    Abstract: A method of processing vegetable oil in which non-toxic reagents are used, so that a waste stream is evolved suitable for use as a nutrient source and wherein the non-toxic reagents include nutrient components whereby the nutrient value of the waste stream is enhanced.
    Type: Grant
    Filed: August 4, 1992
    Date of Patent: May 3, 1994
    Inventor: Ralph S. Daniels
  • Patent number: 5275639
    Abstract: A process for oxidizing aqueous elemental phosphorus containing residues (sludges) to produce orthophosphate containing slurries suitable for subsequent reaction with ammonia to produce nitrogen- and phosphorus-containing fertilizer products. It comprises reacting aqueous elemental phosphorus containing residues with certain special mixtures of concentrated nitric acid and sulfuric acid to effect the conversion of the elemental phosphorus content of the residues into mostly orthophosphoric acid and very little orthophosphorous acid with the relative ratios of orthophosphoric acid to orthophosphorous acid produced being dependent upon the weight ratio H.sub.2 SO.sub.4 :HNO.sub.3 employed in the processing. The reaction is conducted at the boiling point of the resulting aqueous reaction medium.
    Type: Grant
    Filed: March 10, 1993
    Date of Patent: January 4, 1994
    Assignee: Tennessee Valley Authority
    Inventors: Jack M. Sullivan, Raymond D. Thrasher, Ronald E. Edwards
  • Patent number: 5211735
    Abstract: The invention aims at a process for preparing phosphated or nitrophosphated fertilizers through reaction of phosphate rock in aqueous pulp, with sulfuric and/or phosphoric acids, with addition, or not, of ammonia, so as to produce fertilizers of the types simple, double or triple superphosphates, nitrogen-bearing (or not) phosphated partially acidulated, and superphosphated ammoniated, the product being adequate for use as a fertilizer, either powdered or slurried.The invention allows for a more complete reaction due to the better contact between the liquid and solid reagents besides the complete utilization of the heat produced in the reaction as well as in the acid dilution in the aqueous medium, for the vaporization of the water present in the process.
    Type: Grant
    Filed: August 15, 1991
    Date of Patent: May 18, 1993
    Assignee: Petroleo Brasileiro S. A.
    Inventors: Fabio G. M. Costa, Alberto C. C. Da Silva, Paulo C. W. De Albuquerque, Alberto Laranjeira
  • Patent number: 4836843
    Abstract: A method of fertilizing soil comprising the steps of treating soapstock with an acid containing phosphorus compounds, separating the acid oil from the acid water, and using the resulting acid water as fertilizer, or fertilizer component. Such use is particularly effective in precision fertilizer delivery systems having small passages which would be adversely affected by insolubles.
    Type: Grant
    Filed: April 8, 1988
    Date of Patent: June 6, 1989
    Inventor: Ralph S. Daniels
  • Patent number: 4834787
    Abstract: A process providing solubilization of phosphate rock by contacting the rock with sulfurous acid in the presence of an oxidizing agent selected from the group consisting of hydrogen peroxide and ozone. Use of sulfurous acid in combination with a substoichiometric amount of hydrogen peroxide significantly enhances the solubilization of phosphate rock.
    Type: Grant
    Filed: April 3, 1987
    Date of Patent: May 30, 1989
    Assignee: Dolores R. Pircon
    Inventors: Jerome S. Ratliff, Ladislav J. Pircon
  • Patent number: 4710364
    Abstract: A process for removing sulfur dioxide from flue gas is disclosed. After passing through a precipitator to remove particulate material, the flue gas is conducted continuously through a fixed bed solid-gas contacting device containing activated carbon or natural zeolite. The bed is regenerated continuously, thereby producing sulfuric acid which may be mixed with ground phosphate rock to produce normal superphosphate, or other by-products.
    Type: Grant
    Filed: September 10, 1986
    Date of Patent: December 1, 1987
    Assignee: Advanced Separation Technologies Incorporated
    Inventor: W. Wes Berry
  • Patent number: 4650682
    Abstract: Apparatus and process for chemically treating particulate solids material in free flowing condition with fluid reactants in a drum reactor having an acidifying chamber in which acid is introduced into the solids material and an ammoniation chamber in which ammonia is introduced into the solids material.
    Type: Grant
    Filed: February 23, 1983
    Date of Patent: March 17, 1987
    Assignee: Agro-Systems Inc.
    Inventor: Arthur R. Shirley, Jr.
  • Patent number: 4594090
    Abstract: A method of making fertilizer comprising the steps of mixing an aqueous solution of sulfuric acid with diammonium phosphate in a weight ratio of diammonium phosphate to sulfuric acid from about 3 to about 5, and mixing the resulting reaction products with urea in a weight ratio of urea to sulfuric acid from about 7 to about 10. The resulting fertilizer has low corrosion properties and has a salt-out temperature below about 0.degree. F.
    Type: Grant
    Filed: October 15, 1985
    Date of Patent: June 10, 1986
    Inventor: Wallace Johnson
  • Patent number: 4568374
    Abstract: The object of the invention comprises a process for the preparation of fertilizers by solubilizing phosphate rocks containing impurities, which make processing thereof difficult.The process is a simple and direct one. The product thus prepared is easily handled, can be directly used as a powdered fertilizer and dispenses with any post-treatment steps, such as purification, filtration, etc.The rock is solubilized with acid ammonium sulfate or a mixture thereof with sulfuric acid. This acid ammonium sulfate can be formed "in situ", by the reaction of ammonium sulfate and sulfuric acid.Reaction may take place in a mixing reactor, on a belt conveyor or in a granulator.
    Type: Grant
    Filed: August 10, 1984
    Date of Patent: February 4, 1986
    Assignee: Petroleo Brasileiro S.A. - Petrobras
    Inventors: Alberto C. Carneiro da Silva, Fabio G. Martins Costa, Hosam A. Abdallah-Rehim, Elisabeth M. Moreira, Gloria M. G. Soares, Jaime C. da Silva
  • Patent number: 4522638
    Abstract: A process for regulating the NH.sub.3 content in an organic liquid that acts as a physical scrubbing agent and is used in a procedure for absorbing sour gases from gaseous mixtures. To ensure undisturbed and reliable carrying out of the scrubbing process, an ammonia-precipitating precipitant is added to the scrubbing agent and the precipitate is then separated from the scrubbing agent. Preferred precipitants include sulphuric acid and phosphuric acid. The ammonia salts are effective fertilizers.
    Type: Grant
    Filed: May 22, 1984
    Date of Patent: June 11, 1985
    Assignee: Linde AG
    Inventor: Heinz Karwat
  • Patent number: 4469504
    Abstract: A rapid, low temperature process for solubilizing phosphate rocks having high content of foreign matter or a low phosphorus content to obtain: (a) a slow release fertilizer of the NP type; (b) phosphoric acid of high concentration plus MAP; and (c) DAP.
    Type: Grant
    Filed: August 24, 1982
    Date of Patent: September 4, 1984
    Assignee: Petroleo Brasileiro S.A. - Petrobras
    Inventors: Hossam Abdel-Hehim, Wagner C. Coelho, Gloria M. G. Soares
  • Patent number: 4462972
    Abstract: A process for producing fertilizer-grade phosphoric acid is disclosed. In the process, a rock slurry is produced from a predetermined quantity of phosphate rock and a predetermined quantity of pond water neutralized with ammonia. A predetermined rate of sulfuric acid is added to the rock slurry to produce a reaction mixture. The improvement comprises maintaining an excess of sulfate ion in the reaction mixture.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: July 31, 1984
    Assignee: CF Industries, Inc.
    Inventor: William A. Satterwhite
  • Patent number: 4397675
    Abstract: Stable, urea-sulfuric acid reaction products of predetermined composition containing mono- and/or diurea sulfates and less than 35 weight percent water are produced from concentrated, urea-sulfuric acid reaction product feeds of different compositions by simultaneously and separately adding a selected feed solution and reactant urea and/or sulfuric acid, and optionally water, to a reaction zone in stoichiometric proportions so that the composition of the total feed to the reaction zone corresponds to the predetermined composition. Reaction temperature is maintained at a level below the incipient decomposition temperature of the predetermined composition, and the resulting products are essentially or completely free of sulfamic acid and/or ammonium sulfamate.
    Type: Grant
    Filed: November 5, 1981
    Date of Patent: August 9, 1983
    Assignee: Union Oil Company of California
    Inventor: Donald C. Young
  • Patent number: 4388101
    Abstract: A "non-pressure" liquid fertilizer containing nitrogen and sulfur can be prepared by a process comprising (a) mixing sulfuric acid in water, (b) dissolving urea into the resulting solution, and (c) adding anhydrous ammonia in an amount sufficient to bring the pH of the solution to between about 6 and 8. The resulting liquid fertilizers can typically contain in the range of about 19 to about 25% nitrogen and in the range of about 3 to 6% sulfur and remain substantially free from crystals when stored at temperatures above about 40.degree. F. A 19-0-0 liquid fertilizer containing about 3% S (as sulfate) remained crystal free when stored for about a month at about 32.degree. F. The "non-pressure" liquid can be blended with dispersion-type fertilizers. Dispersion-type fertilizers of low phosphate content can be made by substituting phosphoric acid for some or all of the sulfuric acid.
    Type: Grant
    Filed: March 14, 1979
    Date of Patent: June 14, 1983
    Assignee: Occidental Chemical Agricultural Products, Inc.
    Inventor: Robert L. Lowder
  • Patent number: 4336053
    Abstract: A stable liquid fertilizer solution containing nitrogen, phosphorus, iron and optionally sulfur is prepared by mixing a water-soluble iron compound with ammonium polyphosphate and water to produce an iron phosphate slurry having a molar ratio of polyphosphate phosphorus to iron of at least about 2:1, adding ammonia to the iron phosphate slurry to produce a solubilized iron complex; and adding an inorganic acid to the iron complex solution. The amount of acid added is generally that which brings the pH of the fertilizer solution to within the range of about 5.5 to 7.0.
    Type: Grant
    Filed: June 10, 1980
    Date of Patent: June 22, 1982
    Assignee: Phillips Petroleum Company
    Inventor: Joseph R. Kenton
  • Patent number: 4321077
    Abstract: The subject of the invention is the method of preparation of multicomponent fertilizers based upon the decomposition process of mineral phosphate material by ammonium sulphate and sulphuric acid. This method has application in chemical industry.The invention concerns the method of preparation of multicomponent fertilizers relying upon the decomposition of mineral phosphate material by sulphuric acid and ammonium sulphate. The basis of the method relies upon the mineral phosphate material undergoing wet milling with the acid and sulfate and as a result of which mechanically-induced chemical processes occur the decomposition of the apatite structure of material takes place. The milled mixture is introduced into reactors-crystallizers, where further decomposition of the phosphate material and phosphate gypsum crystallization takes place.
    Type: Grant
    Filed: April 2, 1980
    Date of Patent: March 23, 1982
    Assignee: Politechnika Wroclawska
    Inventors: Jerzy Schroeder, Henryk Gorecki, Mieczyslaw Lewandowski, Adam Pawelczyk, Antoni Kuzko
  • Patent number: 4308049
    Abstract: A process is disclosed for the absorption of gaseous or liquid ammonia in acid solutions or slurries, including an ammonia absorption zone separated from a water vapor generation zone disposed at a higher level. A pressure difference is created between the two zones, so that the ammonia absorption takes place completely in the neighborhood of the point of inflow of the ammonia, with a temperature increase localized only near to said inflow point, and thus without giving rise to the generation of water vapor which therefore takes place in a liquid-vapor separation zone located at a higher level with respect to the ammonia absorption zone. The acid solutions or slurries to be neutralized may consist essentially of solutions of phosphoric acid, sulphuric acid, nitric acid, solutions resulting from the nitric acid attack on phosphorites, acid slurries resulting from nitric acid attack or sulphonitric acid attack on phosphorites, or mixtures thereof.
    Type: Grant
    Filed: November 28, 1978
    Date of Patent: December 29, 1981
    Assignee: Montedison, S.p.A.
    Inventor: Iti Mini
  • Patent number: 4252553
    Abstract: A process for the production of fertilizer by reacting sulfur oxide containing gas and water in a multiple state reactor to form sulfur containing acid and reacting the sulfur containing acid with a basic salt which may be solubilized as a result of the acid-base reaction, the basic salt selected from the group consisting of calcium, ammonium and potassium ions, the calcium being derived from a salt selected from the group consisting of phosphatic and nitrogeneous salts, to form a fertilizer selected from the group consisting of phosphatic, nitrogeneous and potassium fertilizers and combinations thereof. The combined sulfur oxide absorption and solubilization of basic salts is conducted at the solution pH of 2.5 to 5. To enhance the further absorption of the sulfur oxide, a solution pH of 3 to 8 is used. This process is suitable for the utilization of sulfur oxides resulting from the combustion of high sulfur containing fossil fuels and sulfur producing chemical processes.
    Type: Grant
    Filed: May 11, 1979
    Date of Patent: February 24, 1981
    Inventors: Ladislav J. Pircon, Ralph E. Peck
  • Patent number: 4231780
    Abstract: A layer of bare, untreated phosphate rock granules is applied to the soil, and concentrated sulfuric acid is supplied thereto. The sulfuric acid is sufficiently concentrated so as to be containable by cold-rolled carbon steel, and sufficiently viscous to cling to the granules to react therewith. Sulfuric acid in excess of the amount needed for reaction with the phosphate rock can be added to correct alkaline conditions in the underlying soil. The reaction of sulfuric acid with the phosphate rock produces substantial quantities of available phosphate and gypsum.
    Type: Grant
    Filed: September 3, 1976
    Date of Patent: November 4, 1980
    Assignee: Chemsoil Corporation
    Inventor: Dwight D. Collins
  • Patent number: 4177053
    Abstract: Phosphoric acid with a high fertilizer-nutrient content is produced by decomposing phosphate rock with nitric acid followed by precipitation of calcium ions with sulfate. The steps of the process are as follows:A. Decomposing phosphate rock with (7-2x) to (17-2x) mol nitric acid and x mols sulfuric acid per mol phosphorous pentoxideA.sub.1 whereby x may take on any values between 0 and a maximum value X, which is limitedA.sub.2 by the condition that the mol ratio H.sub.2 SO.sub.4 :HNO.sub.3 may never exceed the value 8:1 andA.sub.3 by the condition that in the decomposition solution, into which, if need be, also ammonium sulfate is introduced, the content of sulfate ions after precipitation of the semihydrate gypsum is between 10 to 150 g/l solution;B. Adding--if no or not enough sulfuric acid has been used for precipitating calcium sulfate--ammonium sulfate in amounts corresponding to condition A.sub.
    Type: Grant
    Filed: July 6, 1976
    Date of Patent: December 4, 1979
    Assignee: Veba-Chemie Aktiengesellschaft
    Inventor: Hans-Friedrich Kurandt
  • Patent number: 4175944
    Abstract: The invention provides a novel process for the removal of fluorine during the production of fertilizer by precipitating the ion during the ammoniation step and recovering same by pyrolysis.To recover the fluorine the fertilizer is first separated out as a filtrate and the precipitate is heated to evolve ammonium fluoride, which heating is done in an ammonia atmosphere.
    Type: Grant
    Filed: June 26, 1978
    Date of Patent: November 27, 1979
    Assignee: Mobil Oil Corporation
    Inventor: George C. Johnson
  • Patent number: 4168150
    Abstract: A process for the production of fertilizer by reacting sulfur oxide containing gas and water in a multiple state reactor to form sulfur containing acid and reacting the sulfur containing acid with a basic salt which may be solubilized as a result of the acid-base reaction, the basic salt selected from the group consisting of calcium, ammonium and potassium ions, the calcium being derived from a salt selected from the group consisting of phosphatic and nitrogeneous salts, to form a fertilizer selected from the group consisting of phosphatic, nitrogeneous and potassium fertilizers and combinations thereof. The combined sulfur oxide absorption and solubilization of basic salts is conducted at the solution pH of 2.5 to 5. To enhance the further absorption of the sulfur oxide, a solution pH of 3 to 8 is used. This process is suitable for the utilization of sulfur oxides resulting from the combustion of high sulfur containing fossil fuels and sulfur producing chemical processes.
    Type: Grant
    Filed: October 27, 1977
    Date of Patent: September 18, 1979
    Assignee: Ladislav J. Pircon
    Inventors: Ladislav J. Pircon, Ralph E. Peck
  • Patent number: 4077794
    Abstract: A soil modifier comprising from 80 to 95% by weight of a mixture of ferric oxide and ferric sulphate in an oxide/sulphate weight ratio of from 0.25:1 to 1:1, is prepared by calcining at 500.degree.-600.degree. C in an oxidizing atmosphere a blend of by-product obtained in the manufacture of titanium oxide by the sulphate process, with at least 20% by weight with respect to said by-product, of a material based on ferric sulphate and/or ferric oxide. Calcining is then continued under the same conditions, replacing said material in the blend continuously fed in by a recycle fraction of the product continuously discharged.
    Type: Grant
    Filed: March 8, 1977
    Date of Patent: March 7, 1978
    Assignee: Societa' Italiana Resine S.I.R. S.p.A.
    Inventors: Luigi Piccolo, Antonio Paolinelli
  • Patent number: 4073635
    Abstract: Crude phosphate is leached with nitric acid to produce an acid slurry, which is thereafter neutralized with ammonia in two successive stages while simultaneously cooling it and adding acid, part of the crude phosphate phosphorus being replaced with phosphoric acid added to the slurry to be neutralized, and in such a manner that at maximum 40% of the phosphoric acid is fed to the first neutralization stage and the rest is fed to the second neutralization stage, whereby the acidity of the slurry is adjusted to pH 2.5 - 4.5 during the first and to pH 5.0 - 6.0 during the second neutralization stage.
    Type: Grant
    Filed: May 14, 1976
    Date of Patent: February 14, 1978
    Assignee: Kemira Oy
    Inventor: Pekka I. J. Suppanen
  • Patent number: 4073634
    Abstract: A process for the production of fertilizer comprising reacting sulfur oxide containing gas and water in a multiple state reactor to form sulfur containing acid, reacting the sulfur containing acid with a basic ion selected from the group consisting of calcium, ammonium and potassium ions, the calcium being derived from a salt selected from the group consisting of phosphatic and nitrogeneous salts, to form a fertilizer selected from the group consisting of phosphatic, nitrogeneous and potassium fertilizers and combinations thereof. This process is suitable for the utilization of sulfur oxides resulting from the combustion of high sulfur containing fossil fuels and sulfur producing chemical processes. The process of this invention enables the utilization of low concentration sulfur acid in the acidification of phosphate rock utilizing a multiple state reactor.
    Type: Grant
    Filed: April 16, 1976
    Date of Patent: February 14, 1978
    Inventors: Ladislav J. Pircon, Ralph E. Peck
  • Patent number: 4045205
    Abstract: Soil modifiers comprising from 80 to 95% by weight of a mixture of ferric oxide and ferric sulphate in an oxide/sulphate weight ratio of from 0.2:1 to 2:1 are prepared by calcining at 500.degree.-600.degree. C in the presence of an oxidizing gas a material consisting essentially of ferrous sulphate with an average number of molecules of crystallization of from 1 to 5 obtained by partial dehydration of the waste materials, consisting essentially of ferrous sulphate heptahydrate, obtained in the manufacture of titanium dioxide from ilmenites or ilmenite slags by the sulphate process. These modifiers are particularly suitable for clay soils.
    Type: Grant
    Filed: July 7, 1976
    Date of Patent: August 30, 1977
    Assignee: Societa Italiana Resine S.I.R. S.p.A.
    Inventors: Luigi Piccolo, Gabriele Bottai, Antonio Paolinelli, Angelo La Rovere
  • Patent number: 4028087
    Abstract: A process for the production of a granular fertilizer material from sludge materials discharged from scrubbing processes that remove pollutants from boiler flue gases. Waste sludge discharged from flue gas scrubber systems often contain large amounts of calcium and sulfur as well as lesser amounts of other compounds known to have plant nutrient value. The sludge is treated with an acid such as phosphoric, sulfuric or nitric, or a mixture of these, and ammonia. The resulting sludge-ammonia-acid salt mixture is combined with partially dried, previously processed solid material (recycle) in a horizontal rotating vessel. Additional ammonia and/or acid is added to the rotating vessel to cause the sludge-salt mixture to solidify and granulate. Other plant nutrients may be added to the rotating vessel during granulation. The granulated material discharged from the rotary vessel is further processed (dried, cooled, and screened) to obtain desirable moisture content and particle size.
    Type: Grant
    Filed: October 18, 1976
    Date of Patent: June 7, 1977
    Assignee: Tennessee Valley Authority
    Inventors: James J. Schultz, Vincent J. Van Pelt
  • Patent number: 4007030
    Abstract: In the process according to the invention, raw phosphate rock is decomposed with an aqueous solution of sulfuric acid and ammonium sulfate recycled from the conversion step of phosphogypsum into chalk, and then the decomposition liquor stream is divided into a partial acid plant stream (Liquor I) to be converted into phosphoric acid and a partial fertilizer plant stream (Liquor II) to be processed to a multi-component mineral fertilizer. From the acid plant stream (Liquor I) constituting up to 30 per cent by weight of the total decomposition stream, ammonium sulfate is precipitated and introduced into the fertilizer plant stream (Liquor II), all the above mentioned processes of decomposition, separation and precipitation being carried out continuously.
    Type: Grant
    Filed: March 2, 1976
    Date of Patent: February 8, 1977
    Assignee: Przedsiebiorstwo Projektowania I Dostaw Kompletnych Obiektov Przemyslowych "Chemadx"
    Inventors: Jerzy Schroeder, Jerzy Synowiec, Tadeusz Zrubek, Henryk Gorecki, Zdzislaw Wolnicki, Roman Hnatowicz
  • Patent number: 3979199
    Abstract: Pulverized phosphate rock is spread onto or mixed into soil which is to be fertilized. The soil is then treated with a solution of sulfurous acid, usually the output of a device which burns sulfur in air to form sulfur dioxide and then dissolves the sulfur dioxide in water. The water may be irrigation water which thereupon both irrigates the soil and reacts with the phosphate rock to fertilize the soil. Common phosphate ores include a substantial amount of calcium, with which, and with oxygen, the sulfurous acid reacts to form gypsum (calcium sulfate). Gypsum is a widely-used corrective substance applied to croplands, and the gypsum formed by this treatment reduces the requirement to purchase gypsum as a product separate from the fertilizer. Substantially all of the phosphorus contained in the rock can ultimately be solubilized as "available phosphate", with the use of this process.
    Type: Grant
    Filed: March 10, 1975
    Date of Patent: September 7, 1976
    Assignee: Chemsoil Corporation
    Inventors: Dwight D. Collins, Fred W. Lauer, Jr.
  • Patent number: 3962329
    Abstract: The preparation of isobutylidenediurea from isobutyraldehyde and urea, the particle size of the product being controlled by alternate use of sulfuric acid and phosphoric acid.
    Type: Grant
    Filed: October 25, 1974
    Date of Patent: June 8, 1976
    Assignee: BASF Aktiengesellschaft
    Inventors: Guenther Schoenaich, Otto Grabowsky, Johann Mayer, Guenther Matthias
  • Patent number: 3947262
    Abstract: A method of producing phosphorus-containing fertilizers, wherein the phosphate raw stock is treated with a mineral acid selected from the group, consisting of phosphoric acid, sulphuric acid and a mixture of both. The thus-obtained suspension of the phosphorus-containing fertilizers is acted upon by acoustic vibrations at a frequency of from 500 to 20,000 Hz and a second energy density of from 0.5 to 5 W/cm.sup.2, whereupon the end product is isolated.
    Type: Grant
    Filed: July 27, 1973
    Date of Patent: March 30, 1976
    Inventors: Nikolai Mikhailovich Baklanov, Ljubov Pavlovna Buslakova, Raisa Mikhailovna Nekorystnova, Anatoly Artemievich Novikov, Tatyana Grigorievna Repenkova, Ivan Ivanovich Rumyantsev, Galina Alexandrovna Sapogova, Nikolai Pavlovich Solodovnik, Viktor Mironovich Fridman
  • Patent number: RE29149
    Abstract: Ammonium phosphate solutions free of precipitates are prepared from wet-process phosphoric acid containing incidental metallic impurities such as iron, aluminum and magnesium by concentration of the phosphoric acid to an anhydrous state and the formation of acyclic polyphosphoric acids therein which prevent the precipitation of the metallic impurities upon neutralization. The acid is heated to a temperature greater than 120.degree. C. at atmospheric or subatmospheric pressures while removing the volatile impurities and thereafter is neutralized with ammonia. The neutralization step can be performed at elevated temperatures with anhydrous ammonia or the acid can be cooled and neutralized at ambient temperatures. The resulting ammonium phosphate is diluted with water to obtain an ammonium phosphate solution which is clear and free of precipitates.
    Type: Grant
    Filed: July 3, 1967
    Date of Patent: March 8, 1977
    Assignee: Union Oil Company of California
    Inventor: Donald C. Young
  • Patent number: RE29458
    Abstract: Fertilizer materials, especially potassium dihydrogen phosphate, are produced by the reaction of phosphate rock or a solubilized form thereof, such as mono calcium phosphate, dicalcium phosphate, etc., concentrated sulfuric acid, potassium hydrogen sulfate and, optionally fresh or recycle phosphoric acid, the resulting mixture is filtered to remove the calcium sulfate precipitate and the potassium dihydrogen phosphate is recovered from the filtrate, either by concentration and filtration or by extraction with an organic solvent.
    Type: Grant
    Filed: July 18, 1975
    Date of Patent: October 25, 1977
    Assignee: Pennzoil Company
    Inventors: Erhart K. Drechsel, John B. Sardisco, James R. Stewart, Jr.
  • Patent number: T101901
    Abstract: A process for the production of fluid fertilizers (suspensions and/or solution type) made from merchant-grade phosphoric acid (50-58 percent P.sub.2 O.sub.5), sulfuric acid, liquid anhydrous ammonia, and water, wherein liquid ammonia is heated in heat exchange means juxtaposed hot fertilizer product to form gaseous ammonia, which gaseous ammonia, along with phosphoric acid and sulfuric acid, is fed to a pipe-cross reactor wherein a melt of ammonium polyphosphate sulfate is formed, which melt is subsequently mixed with cooled recycled product to produce a fluid fertilizer with N:P.sub.2 O.sub.5 weight ratios ranging from about 0.3 to 1, which contains from about 10 to 60 percent of its P.sub.2 O.sub.5 values in the form of polyphosphates and 3 to 8 percent by weight sulfur. About 45 percent of the P.sub.2 O.sub.5 as polyphosphate is easily attainable in the product with ambient acid feed temperatures, i.e., about 50.degree. F. to 100.degree. F.
    Type: Grant
    Filed: July 20, 1981
    Date of Patent: June 1, 1982
    Inventors: Frank P. Achorn, Kenneth E. McGill