Abstract: A fine bubble generator may include an inlet; an outlet; a first fine bubble generation portion; and a second fine bubble generation portion. The first fine bubble generation portion includes: a diameter-reducing flow path and a diameter-increasing flow path. The second fine bubble generation portion includes: a first swirling flow generation portion; and a second swirling flow generation portion. The first swirling flow generation portion includes: a first outer peripheral portion; and a plurality of first vanes disposed configured to generate a first swirling flow flowing in a first swirling direction with respect to a center axis of the second fine bubble generation portion. The second swirling flow generation portion includes: a second outer peripheral portion; and a plurality of second vanes configured to generate a second swirling flow flowing in a second swirling direction opposite to the first swirling direction with respect to the center axis.

Abstract: A method for production of ammonium phosphate from phosphate rock slurry. The method includes: introducing flue gas containing SO2 into a phosphate rock slurry, to yield an absorption solution; evaporating waste ammonia water containing 10-20 wt. % ammonia to yield ammonia gas; introducing the ammonia gas into the absorption solution at a temperature of 110-135° C. until a neutralization degree of the absorption solution reaches 1.5-1.6, thus yielding an ammonium phosphate solution and calcium sulfate; separating the calcium sulfate from the ammonium phosphate solution; and introducing the ammonium phosphate solution to a granulator for granulation to yield ammonium phosphate granules; drying and sieving the ammonium phosphate granules, thereby yielding ammonium phosphate.

Abstract: The invention relates to a method for manufacturing an ammonium phosphate fertilizer from a phosphoric acid aqueous solution that has less than 50% P2O5 concentration and is obtained by wet phosphate ore treatment, said phosphoric acid containing traces of cadmium, comprising the following steps: (a) neutralizing said phosphoric acid solution (1) with ammonia (3) up to a molar ratio N/P of between 0.1 and 0.8, (b) reacting said partially neutralized solution (4) with a sulfide source (6) so as to form a cadmium sulfide precipitate (9), (c) separating said precipitate (9) so as to obtain a refined ammoniated phosphoric acid solution (10), (d) ammoniating and granulating said refined solution (10) so as to form said fertilizer (12).

Abstract: Colorless dental compositions for restoring the enamel layer of a tooth are disclosed. The colorless enamel compositions are combined with pigmented dentin compositions to provide a true color match and natural esthetics. Methods that utilize the compositions in placement/build-up techniques in direct restorations are also disclosed.

Abstract: A method for production of ammonium phosphates includes providing (210) of a phosphorus-loaded water immiscible liquid phase, adding (212) of anhydrous ammonia to the water immiscible liquid phase, precipitating (214) of mono-ammonium phosphate and/or di-ammonium phosphate from the water immiscible liquid phase and extracting (218) of the precipitated mono-ammonium phosphate and/or di-ammonium phosphate from the water immiscible liquid phase. The method further includes controlling (216) of a temperature of the water immiscible liquid phase during the adding (212) and precipitating (214) to a predetermined temperature interval.

Abstract: The invention provides a method for the combined production of (i) a fertilizer selected from the group consisting of ammonium nitrate, ammonium phosphates or a combination thereof, (ii) a concentrated stream of CO2 through an indirect neutralization of ammonia with an acid selected from the group consisting of nitric acid, phosphoric acid, a salt thereof and a combination thereof; said method comprising: (I) reacting a carbonate product with a reagent selected from the group consisting of nitric acid, phosphoric acid, a salt thereof, and a mixture thereof to form CO2, and a fertilizer containing an ammonia component; and (II) separating at least a portion of said carbon dioxide from said fertilizer in a condensed and relatively concentrated stream.

Abstract: A material for cement which comprises a calcium salt powder with an inositol phosphate and/or a salt thereof as adsorbed on the surface thereof, the powder having a specific surface area of 60-120 m2/g. A method of producing a material for cement comprises the step of mixing a calcium ion-containing solution adjusted to alkalinity with a phosphate ion-containing solution to produce a precipitate, the step of maturing the precipitate-containing system while maintaining the alkalinity to obtain a calcium salt powder, the step of recovering the calcium salt powder and drying the same, and the step of immersing the dried calcium salt powder in a solution containing an inositol phosphate and/or a salt thereof to cause the inositol phosphate and/or salt thereof to be adsorbed on the surface of the calcium salt powder.

Abstract: The invention provides a method for the combined production of (I) a sulfur oxide containing product and (II) a fertilizer selected from a group consisting of ammonium nitrate, ammonium phosphates and a combination thereof, through an indirect neutralization of ammonia with an acid selected from the group consisting of nitric acid, phosphoric acid and a combination thereof, the method comprising: a. contacting a precipitate containing calcium sulfite with a solution of nitric acid and a solution of ammonia in two separate steps, to form the fertilizer, the sulfur oxide containing product and a precipitate containing calcium hydroxide; and b. separating at least portion of the fertilizer, the sulfur oxide and the calcium hydroxide into three separated streams.

Abstract: A catalytic converter has a housing. The housing defines a conduit and has a support wall defining an opening in the conduit. A removable catalyst element covers the opening for treating an exhaust gas passing through the conduit. A removable bar abuts the catalyst element. A first end of the bar is anchored to the wall and a second end of the bar is bolted to the wall thus clamping the catalyst element between the wall and the bar.

Abstract: The present invention provides a process for removing ammonia as an aqueous salt solution from an acid gas comprising ammonia and hydrogen sulfide. A strong acid, such as sulfuric acid, is used as a scrubbing agent to convert ammonia to an ammonium salt. Control of pH and stripping in combination with reboiler or evaporators reduces hydrogen sulfide concentration. The ammonium salt is produced as an aqueous solution, which may crystallized to form a solid product. The ammonium salt solution or solid may be used as a fertilizer.

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 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.

Abstract: Addition of an aminosulfonate product to an inorganic nitrogen-containing salt provides a composition of matter with improved properties. In particular, 2-acrylamido-2-methylpropanesulfonic acid and its derivatives can be added to ammonium nitrate to provide improved prills.

Abstract: This invention relates to novel room-temperature process for obtaining calcium phosphate, in particular hydroxyapatite, coatings and microspheres that encapsulate drugs, proteins, genes, DNA for therapeutical use. The coatings and microspheres are designed to perform a defined biological function related to drug delivery, such as gene therapy through gene delivery. A novel method for encapsulation, and subsequent controlled release of therapeutically active agents from such biofunctional coatings and microspheres is disclosed. Such coatings and microspheres are useful for side-effects free, long-term, targeted, controlled release and delivery of drugs, proteins, DNA, and other therapeutic agents.

Abstract: A stable, phase-pure magnesium-substituted crystalline hydroxyapatite containing from about 2.0 to about 29 wt % magnesium, wherein at least 75 wt % of the magnesium content is substituted for calcium ions in the hydroxyapatite lattice structure.

Abstract: A process of forming a mixture of diammonium phosphate and triammonium phosphate by the reaction of phosphoric acid with gaseous ammonia in a spray column. In the process, the reaction occurs under pressure. With the appropriate selection of the ammonia pressure and the phosphoric acid feed rate sprayed into the spray column, the amount of each of the diammonium phosphate and triammonium phosphate formed can be controlled.

Abstract: A process for the preparation of granular fertilizer grade DAP (a product composed of ammonium phosphates, principally diammonium phosphate, resulting from the ammoniation of phosphoric acid, as defined in Official Publication No. 52 of the Association of American Plant Food Officials, dated 1999) comprising partially preneutralizing orthophosphoric acid with ammonia, completing the ammoniation of the orthophosphoric acid with ammonia in a rotary ammoniator-granulator to provide granular DAP, sizing the granular DAP to provide the granular DAP product, reducing the particle size of the oversized granular DAP, and recycling the undersized granular DAP and the sized-reduced oversized granular DAP to the ammoniator-granulator.

Abstract: A process for manufacturing ammonium salts using a reactor which includes a first tubular reaction chamber having at least one acid feed and at least on ammonia feed which are arranged in a first up-stream part of the reactor. At least one second ammonia feed is introduced into a second part of the reactor which is arranged as an extension of the first and which includes, in a flow direction, a convergent segment, a cylindrical tube and a divergent segment. The second ammonia feed communicates with the second part in the vicinity of the convergent segment and the processes is controlled to obtain basic vapors at an outlet of the reactor.

Abstract: There is disclosed a caking inhibitor for mono-and diammonium phosphates which is water soluble and effective at small concentrations rendering the phosphates acceptable in most utilities without separation of the inhibitor. The inhibitor is sodium sulfate. Effective amounts of this salt range from about 0.5 percent to about 1 percent by weight in the ammonium phosphates. It is particularly advantageous that this salt is useful in both types of ammonium phosphates.

Abstract: This invention is a process for removing NH.sub.3 from a NH.sub.3 -containing liquid stream. The process contains the following steps: (a) passing a NH.sub.

Abstract: An improved batch process for the production, in equipment readily available at the fertilizer dealer level, of high-analysis stable ammonium orthophosphate suspension fertilizers effected by the ammoniation of solid intermediates derived from wet-process orthophosphoric acids or combinations of the solid intermediates with such wet-process type acid or other impure phosphoric acids. Fluorosilicic acid, a by-product of the phosphate industry which is readily available and relatively inexpensive, is utilized as a source of fluoride. The fluorosilicic acid is added to the batch formulation prior to the ammoniation step thereby allowing the fluorosilicic acid to be converted to ammonium fluoride. Subsequently, the metallic impurities are allowed to precipitate as fluoride compounds instead of the usual troublesome impurity-phosphate-water gels which have been identified as causing complete destruction of suspension fluidity during storage.

Abstract: New processes and equipment are disclosed for producing elemental phosphorus and thermal phosphoric acid. Benefits are listed below.1. Phosphorus-containing solids are recycled to smelting furnaces thus eliminating hazardous waste generation.2. Phosphorus furnace feedstock is upgraded and this permits unbeneficiated phosphate ore to be smelted.3. Energy is conserved during manufacture of elemental phosphorus and phosphoric acid.4. Electric energy is produced by cogeneration.5. Fluorine in phosphate ore is recovered as ammonium fluoride.6. Phosphorus-containing liquids are used as feedstock for production of suspension fertilizers.Benefits are achieved by agglomerating phosphate ore with monocalcium phosphate binder by a method which upgrades the ore. Phosphorus-containing solids are fluidized and burned to form an impure phosphoric acid mixture which is reacted with small sized phosphate ore to form monocalcium phosphate binder.

Abstract: A process is developed for producing phosphoric acid and phosphates from wet-process phosphoric acid. The crude acid is extracted with a waterimmiscible solvent mixture consisting of mixed trialkyl phosphine oxide and a diluent, wherein about 2/3 P.sub.2 O.sub.5 in the crude acid is extracted into solvent mixture and the balance remains in the raffinate. Pure phosphoric acid or phosphates are produced by stripping the loaded solvent with appropriate aqueous phase and secondary calcium phosphate fertilizer is obtained by neutralizing the raffinate with calcium carbonate.

Abstract: A process is disclosed for the manufacture of granular diammonium phosphate (DAP) by reacting anhydrous ammonia with phosphoric acid in a reactor to form reaction product consisting of a partially reacted slurry of monoammonium phosphate and diammonium phosphate. The slurry is pumped to a rotary granulator-reactor where it is further reacted with anhydrous ammonia to form a solid granular diammonium phosphate mixture having a range of particle sizes consisting of undersize, oversize and product. After drying the diammonium phosphate mixture, a portion of the dried granular diammonium phosphate mixture is diverted back to the granulator-reactor prior to delivery to a classifying means. The portion of dried granular diammonium phosphate mixture not diverted to the granulator-reactor, is introduced to a classifying means set to a narrow separation to separate undersize and oversize granular particles from the desired product granular particles.

Abstract: A process for the production of dialkali metal phosphates by ion exchange is disclosed. The process is carried out by first ammoniating a water-soluble phosphate source such as phosphoric acid or monocalcium phosphate. The resulting ammoniated phosphate solution is then contacted with a weak cation exchange resin in the alkali metal form to produce the dialkali metal phosphate as well as an ammonium-loaded weak cation exchange resin. The cation exchange resin is regenerated by contacting it with an alkali metal salt solution which effects an exchange of alkali metal from ammonium to produce a rgenerated weak cation exchange resin in the alkali metal form as well as a water-soluble ammonium salt corresponding to the initial alkali metal salt.

Abstract: An aqueous alkali phosphate solution is made. An organic phase is countercurrently mixed with an aqueous phase, the two phases being used in a volume ratio larger than 1:1 and formed aqueous alkali phosphate solution is separated from the remaining organic phase. The two phases are mixed and reacted in a reaction zone comprised of a mixing and separating zone. The organic phase is continuously dispersed in the aqueous phase. A volume excess of aqueous phase is maintained in the mixing zone and the two phases are used in an overall quantity sufficient to provide a volume ratio of organic to aqueous phase of 4:6 to 2:8.

Abstract: The invention relates to a method of recovering nutrients from the flue gases of a fertilizer plant by exposing hot, almost water-saturated reaction gases (4) obtained from the fertilizer production process to a countercurrent scrubbing (5, 6) and by scrubbing the hot gases (19) obtained from the drying (16) of the fertilizer, in order to recover the gaseous impurities present in the gases. According to the invention, the hot gases (19) obtained from the drying of the fertilizer are scrubbed (21) with the scrubbing solution (7) coming from the countercurrent scrubbing (5, 6) of the hot, almost water-saturated reaction gases (4), in order to concentrate this scrubbing solution (7) before it is returned to the fertilizer production process (1-3).

Abstract: An improved continuous process for the production of fertilizers, wherein the reactions, mixing, sizing, and moisture removal required to produce a resultant product are carried out on a simple, flat surface that moves horizontally, and wherein, in the reactor-mixing zone of said surface, the surface movement, the shearing action of moving blades, the moving spargers for distributing reactants and reaction products, the unusually wide dispersion of the reactants and reaction products, and the unusually long retention time and extensive aeration of the final reaction products and reacted product have the useful benefits of low consumption of energy, close product size control, elimination of the need for recycling produced materials as a means of wetness control in the reactor-mixing zone, and of achieving relatively simple, low cost processing.

Abstract: An improved process of concentrating wet process phosphoric acid by continuously contacting an acid feed containing at least about 56 weight percent of P.sub.2 O.sub.5 based on the total weight of the feed with heated gases consisting of air and gaseous fuel combustion products thereby forming a mixture of said gases containing entrained superphosphoric acid particles, continuously coalescing said mixture in a coalescence zone forming coalesced superphosphoric acid and continuously removing the coalesced superphosphoric acid from said coalescence zone.

Abstract: A process is disclosed for the production of water soluble ammonium phosphates, comprising the following steps:(a) to react in a reaction step ammonia and untreated phosphoric acid with P.sub.2 O.sub.5 concentration comprised within the range of from 30 to 54%, outcoming from wet processes;(b) to filter under high temperature conditions the reaction suspension, separating the impurity-containing sludges from an aqueous solution of ammonium phosphate;(c) to cool and crystallize the aqueous solution of ammonium phosphate;(d) to separate the formed ammonium phosphate crystals from the mother liquors.

Abstract: A process for producing purified diammonium phosphate (abbreviated to DAP) directly from wet process phosphoric acid with a high yield is provided, which process comprises reacting wet process phosphoric acid with NH.sub.3 at 50.degree..about.80.degree. C. while keeping the molar ratio of NH.sub.3 /H.sub.3 PO.sub.4 at 1.65-1.90; separating the resulting slurry containing DAP crystals and an insoluble sludge into a slurry containing the former and a slurry containing the latter; treating the former slurry in a conventional manner to recover DAP; while treating the latter slurry by heating it to 60.degree..about.95.degree. C. to dissolve DAP contained therein, removing the sludge by centrifugal separation and concentrating the filtrate to recover DAP; and combining the two portions of DAP.

Abstract: A process for producing purified monoammonium phosphate (abbreviated to MAP) directly from wet process phosphoric acid with a high yield is provided, which process comprises reacting wet process phosphoric acid with NH.sub.3 at 50.degree..about.80.degree. C. while keeping the molar ratio of NH.sub.3 /H.sub.3 PO.sub.4 at 0.9.about.1.35; separating the resulting slurry containing MAP crystals and an insoluble sludge into a slurry containing the former and a slurry containing the latter; treating the former slurry in a conventional manner to recover MAP; while treating the latter slurry by heating it to 60.degree..about.95.degree. C. to dissolve MAP contained therein, removing the sludge by centrifugal separation and concentrating the filtrate to recover MAP; and combining the two portions of MAP.

Abstract: A novel method is provided to produce di-ammonium phosphate fertilizer by operating a DAP reactor and granulator in such a manner that part of the hot exhaust gases from the DAP reactor are diverted into a vaporizer where liquid ammonia is vaporized for use in the DAP reactor and the granulator. Considerable savings in energy and other advantages are achieved through such operation.

Abstract: In the process of the invention spent phosphoric acid is concentrated and stripped with air to a greater than 50% P.sub.2 O.sub.5 concentration to remove nitric acid. As a result of concentrating the spent acid a portion of the aluminum precipitates as monoaluminum phosphate, which is recovered by filtration. The filtrate is then ammoniated to produce a monoammonium phosphate solution. The solids precipitated during ammoniation and comprising aluminum ammonium phosphate which contains other metal phosphates are washed and reacted with aqueous ammonia to form diammonium phosphate.

Abstract: Processes for the preparation of phosphoric acid, such as merchant phosphoric acid, and for the provision of phosphoric acid suitable for the preparation of ammonium phosphates, are disclosed. Such processes comprise providing a source stream of phosphoric acid comprising more than about 30% P.sub.2 O.sub.5, said source stream having impurities, and removing from the source stream a minor proportion, 20% or less, to form a treatment stream. The level of impurities in the treatment stream is reduced employing any of the means known to those skilled in the art, especially solvent extraction. At least a portion of the treated treatment stream is combined with the balance of the source stream to form a product stream. The treated treatment stream and source stream are proportioned so as to render the product stream less susceptible to post-precipitation than the source stream.

Abstract: The process for producing liquid combined fertilizers according to the present invention comprises neutralization of extraction-type phosphoric acid with an excess of gaseous ammonia taken in an amount of 1-1.2 parts by weight relative to the content thereof in the final product at a temperature of the reagents of from 60.degree. to 250.degree. C., mixing of the resulting neutralization products with a liquid phase consisting of water or ammonia water and a portion of the final product recycled to the process; said mixing is conducted under a pressure of 0.05-0.7 atm and at an excess of water in the liquid phase of 1.05-2.0 parts by weight relative to the content thereof in the final product; the process is carried out at a ratio of circulation of the final product of 2 to 40 and at a pressure differential at the stages of neutralization and mixing of from 0.1 to 6 atm.The process according to the present invention may be useful in the agriculture.

Abstract: A method of preparing a purified ammoniated phosphoric acid composition, comprising, reacting an aqueous wet process phosphoric acid with an ammonium ion source at a N/P.sub.2 O.sub.5 weight ratio ranging from about 0.06 to about 0.15 in the presence of solid phase metal ion containing impurities for a time sufficient to precipitate the majority of the impurities in the acid, the impurity precipitation comprising at least several complex metal salts at least one of which contains magnesium, aluminum and fluorine, and obtaining the purified ammoniated phosphoric acid by separating the precipitated impurities therefrom.

Abstract: A process for the partial removal of impurities present in a wet process phosphoric acid used in the production of granulated mono- or di-ammonium phosphate fertilizers in order to control the grade of the final product. All or a portion of the liquid from the primary scrubbers is clarified to remove the precipitated impurities and the clarified flow is then fed into the reactor along with any unclarified portions of the primary scrubber liquid.

Abstract: Processes and compositions of matter are disclosed for the production of liquid fertilizers wherein wastewater from a phosphorus smelting furnace is incorporated in lqiuid fertilizer processes. The wastewater replaces water evaporated and the wastewater dissolves fertilizer salts. A serious water pollution problem is avoided when wastewater is incorporated in liquid fertilizers. The invention discloses a process for making orthophosphate suspension fertilizer wherein impure phosphoric acid is neutralized in the condensing system, water from the condensing system is bled off, and a suspending clay is added to produce orthophosphate suspension fertilizer. In this process, phosphorus sludge made at phosphorus furnaces is used to produce suspension fertilizer, and wastewater from phosphate smelting furnaces is recovered. New compositions of matter are disclosed.

Abstract: A wet process phosphoric acid which has been treated with aluminosilicate after the first stage of clarification can be further stabilized against precipitation of solids during storage and transport and the solids from the crystallizer more economically used to make diammonium and triple superphosphate fertilizers by introducing a second stage of clarification of the acid at a P.sub.2 O.sub.5 concentration of 38 to 42 weight percent.

Abstract: Black carbonaceous floc in wet-process phosphoric acid is removed by contact with an oxidizing agent during the neutralization step with ammonia. In an embodiment the black floc is removed in liquid fertilizers derived from wet-process phosphoric acid by reaction with an oxidizing agent at high temperatures.The oxidizing agent is preferably nitric acid.

Abstract: A process for the manufacture of phosphoric acid from phosphate rock is provided. The phosphate rock is digested or acidulated with an acid solution containing oxalic acid to produce phosphoric acid and calcium oxalate. Useful by-products are also formed and include calcium carbonate and ammonium oxalate. More specifically, the process provides for the production of phosphoric acid, ammonium phosphate and useful by-products utilizing synthesis gas and air to produce oxalic acid and ammonia. The synthesized oxalic acid is utilized for phosphate rock digestion to produce phosphoric acid, which can be reacted with ammonia to produce ammonium phosphate. Calcium oxalate from phosphate rock digestion is utilized to produce calcium carbonate, ammonium oxalate and oxamide.

Abstract: A process and product of waste recovery at phosphorus furnaces is disclosed wherein small sized discrete particles of carbonaceous material or beneficiated phosphate ore are mixed with a mineral axis, an alkaline fluid and water, and the reacted mixture is tumbled in a horizontal cylinder at a temperature below that at which the carbonaceous material oxidizes to form agglomerates which are then indurated to discrete particulate size as desired for a charge component; the agglomerates are fed to a phosphorus smelting furnace together with other materials needed to make elemental phosphorus, furnace gases are cooled with recirculating water, a side stream of the water is taken off, treated, and used as feedstock in fluid fertilizers. The side stream of water contains elemental phosphorus, and the side stream is used as make-up water in fertilizer processes. Apparatus is disclosed for agglomerating coke and phosphate and, further, for measuring the abrasion and shatter resistance of agglomerates.

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.

Abstract: An improved process for the production of concentrated, high-grade, nitrogen-phosphate (N--P.sub.2 O.sub.5) base suspension fertilizer from wet-process or other phosphoric acids and ammonia. The process involves addition of small proportions of fluosilicic acid during preparation of the suspension to cause modification of monoammonium phosphate crystals to shapes and sizes that do not settle during vibration such as occurs during shipment.

Abstract: Ammonium orthophosphate products are prepared by reacting ammonia and phosphoric acid together at high speed under vigorous mixing conditions by spraying the reactants through a two-phase, dual coaxial mixer/sprayer and separately controlling the supply and axial outflow rate of the phosphoric acid at 1 to 10 m/sec. and the outflow rate of ammonia at 200 to 1000 m/sec. (N.T.P.). Thorough mixing and a homogeneous product is obtained by directing the outflow spray into a coaxial cylindrical reaction chamber of a specified size with respect to the diameter of the outermost duct of the sprayer/mixer. The product may be granulated on a moving bed of granules and adjusted in respect of the NH.sub.3 to H.sub.3 PO.sub.4 content by changing the concentration of the phosphoric acid and/or supplying additional ammonia to the granulation bed.

Abstract: An energy efficient process and apparatus is described that allows production of concentrated polyphosphate containing ammonium phosphate suspension fertilizers that can be stored and handled at temperatures well below 0.degree. F. Ammoniation of the merchant-grade wet-process phosphoric acid provides all of the heat required by the process. Use of a unique enlarged dual pipe-type reactor system allows operation for extended periods without clogging. To obtain the high concentration and excellent low temperature storage and handling properties, the ammonium phosphate must be produced within closely specified and previously undisclosed N:P.sub.2 O.sub.5 and solution concentration ranges. Operation outside the specified composition range will reduce the maximum plant food concentration and may cause some of the ammonium phosphate salts to crystallize and foul the heat-transfer surfaces.

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.

Abstract: A process for preparing crystalline ammonium dihydrogen phosphate, comprises the steps of (a) adding a sequestering agent into ammonium hydrogen phosphate aqueous solution, the sequestering agent reacting with metallic ions contained in the aqueous solution to form water solouble compounds, (b) heat-treating the aqueous solution at a temperature of 70.degree. C. or more after addition of the sequestering agent, and (c) crystallizing ammonium dihydrogen phosphate out of the aqueous solution after the heat-treating, so that crystalline ammonium dihydrogen phosphate can be obtained in high whiteness and in the form of columnar crystals.

Abstract: A method of producing purified monoammonium phosphate from wet process phosphoric acid and ammonia is provided. The ammoniation takes place in two stages, the acid being ammoniated in the first stage to a pH between about 1.5 and 2.5. This mixture is allowed to age after which the mixture is ammoniated to a pH between about 4 and 5. An impurity-containing precipitate is formed in the first and second stages of ammoniation that is easily filterable from the monoammonium phosphate solution derived from the second ammoniation stage.

Abstract: Method for production of granular ammonium polyphosphate fertilizer in which ammonium polyphosphate melt is prepared in a simple inline reactor and distributed onto a bed of solids in a drum granulator to bind smaller fertilizer particles into granules. The desired polyphosphate content can be obtained in the granular product by adjusting the total heat input of the feed reactants to the reactor by means of energy conservation modifications to the system. Energy losses from the reaction system are controlled by use of a predetermined quantity of insulation so that varying amounts of the maximum theoretical heat input can be utilized to produce products of polyphosphate contents as desired.