Abstract: A method for the production of potassium sulphate comprising contacting an aqueous potassium- and sulphate-containing composition with magnesium chloride (MgCl2), thereby obtaining a composition comprising kainite; optionally concentrating the kainite from the composition; reacting the kainite with magnesium sulphate (MgSO4) and potassium sulphate (K2SO4) so as to convert the kainite into leonite (K2SO4.MgSO4.4H2O); optionally contacting the leonite with water to remove excess MgSO4; and contacting the leonite with water so as to leach the MgSO4, contained in the leonite, and to at least substantially selectively precipitate potassium sulphate (K2SO4). The method can be operated at higher temperatures, in particular, at temperatures above 35° C., and does not require a cooling step at 20 to 25° C. The method produces potassium sulphate with a low amount of chloride.

Abstract: There are provided methods for the production of potassium sulphate. The methods comprise contacting an aqueous potassium- and sulphate-containing composition with magnesium chloride (MgCl2), thereby obtaining a composition comprising kainite; optionally concentrating the kainite from the composition and reducing or removing halite therefrom; reacting the kainite with magnesium sulphate (MgSO4) and potassium sulphate (K2SO4) so as to convert the kainite into leonite (K2SO4.MgSO4.

Abstract: There are provided methods for the production of potassium sulphate. The methods comprise contacting an aqueous potassium- and sulphate-containing composition with magnesium chloride (MgCl2), thereby obtaining a composition comprising kainite; optionally concentrating the kainite from the composition; reacting the kainite with magnesium sulphate (MgSO4) and potassium sulphate (K2SO4) so as to convert the kainite into leonite (K2SO4.MgSO4.4H2O); optionally contacting the leonite with water to remove excess MgSO4 and contacting the leonite with water so as to leach the MgSO4, contained in the leonite, and to at least substantially selectively precipitate potassium sulphate (K2SO4), and further involving a process brine sulphate control step, based on bloedite precipitation, to control the overall level of sulphate in the method. The method according to the invention can be operated at higher temperatures, in particular at temperatures above 35° C. and does not require a cooling step at 20 to 25° C.

Abstract: There are provided methods for the production of potassium sulphate. The methods comprise contacting an aqueous potassium- and sulphate-containing composition with magnesium chloride (MgCl2), thereby obtaining a composition comprising kainite; optionally concentrating the kainite from the composition; reacting the kainite with magnesium sulphate (MgSO4) and potassium sulphate (K2SO4) so as to convert the kainite into leonite (K2SO4.MgSO4.4H2O); optionally contacting the leonite with water to remove excess MgSO4; and contacting the leonite with water so as to leach the MgSO4, contained in the leonite, and to at least substantially selectively precipitate potassium sulphate (K2SO4). The method according to the invention can be operated at higher temperatures, in particular at temperatures above 35° C. and does not require a cooling step at 20 to 25° C. The method produces potassium sulphate with a low amount of chloride.

Abstract: Methods of processing an aqueous solution comprising potassium sulfate and magnesium sulfate include crystallizing K2SO4, crystallizing recycle crystals, and mixing at least a portion of the recycle crystals with the aqueous solution. Systems for processing potassium sulfate and magnesium sulfate include a first crystallizer and a second crystallizer in fluid communication with the second mix tank. The second crystallizer is structured and adapted to precipitate recycle crystals from the concentrated liquor to form a potassium-depleted recycle brine. The recycle crystals precipitated in the second crystallizer have a composition suitable to be recycled to the first crystallizer to increase the production of SOP.

Abstract: Methods of processing an aqueous solution comprising potassium sulfate and magnesium sulfate include crystallizing K2SO4, crystallizing recycle crystals, and mixing at least a portion of the recycle crystals with the aqueous solution. Systems for processing potassium sulfate and magnesium sulfate include a first crystallizer and a second crystallizer in fluid communication with the second mix tank. The second crystallizer is structured and adapted to precipitate recycle crystals from the concentrated liquor to form a potassium-depleted recycle brine. The recycle crystals precipitated in the second crystallizer have a composition suitable to be recycled to the first crystallizer to increase the production of SOP.

Abstract: Methods of processing an aqueous solution comprising potassium sulfate and magnesium sulfate include crystallizing K2SO4, crystallizing recycle crystals, and mixing at least a portion of the recycle crystals with the aqueous solution. Systems for processing potassium sulfate and magnesium sulfate include a first crystallizer and a second crystallizer in fluid communication with the second mix tank. The second crystallizer is structured and adapted to precipitate recycle crystals from the concentrated liquor to form a potassium-depleted recycle brine. The recycle crystals precipitated in the second crystallizer have a composition suitable to be recycled to the first crystallizer to increase the production of SOP.

Abstract: Methods of processing an aqueous solution comprising potassium sulfate and magnesium sulfate include crystallizing K2SO4, crystallizing recycle crystals, and mixing at least a portion of the recycle crystals with the aqueous solution. Systems for processing potassium sulfate and magnesium sulfate include a first crystallizer and a second crystallizer in fluid communication with the second mix tank. The second crystallizer is structured and adapted to precipitate recycle crystals from the concentrated liquor to form a potassium-depleted recycle brine. The recycle crystals precipitated in the second crystallizer have a composition suitable to be recycled to the first crystallizer to increase the production of SOP.

Abstract: Methods of forming potassium sulfate include calcining polyhalite ore particles to convert the polyhalite ore particles to a water-soluble composition. At least a portion of the water-soluble composition is dissolved in an aqueous medium to form an aqueous solution comprising K+, Mg2+, and SO42? ions and a calcium-containing solid. The calcium-containing solid is separated from the aqueous solution to form a filtrate comprising K+, Mg2+, and SO42? ions. A potassium-containing salt is dissolved in the filtrate to increase the concentration of K+ and SO42? ions to from a concentrated liquor, and K2SO4 is crystallized from the concentrated liquor. A system for processing polyhalite ore includes a countercurrent leaching apparatus, a first mix tank, an evaporator, and at least one crystallizer.

Abstract: A method for converting sodium bicarbonate in a sodium carbonate monohydrate crystallization process to maintain a mother liquor composition in a sodium carbonate monohydrate crystallizer below the invariant point for the crystallizer for reducing or eliminating the cocrystallization of sodium sesquicarbonate crystals in the process. The mother liquor composition may be maintained below the invariant point by stripping carbon dioxide from a feed solution or from mother liquor recycled to the crystallizer.

Abstract: A method for converting sodium bicarbonate in a sodium carbonate monohydrate crystallization process to maintain a mother liquor composition in a sodium carbonate monohydrate crystallizer below the invariant point for the crystallizer for reducing or eliminating the co-crystallization of sodium sesquicarbonate crystals in the process. The mother liquor composition may be maintained below the invariant point by stripping carbon dioxide from a feed solution or from mother liquor recycled to the crystallizer.

Abstract: A process for forming useful sodium salts by uniquely processing dilute brine solutions having sodium bicarbonate concentrations is disclosed. The dilute brine is reduced in sodium bicarbonate content to prevent precipitation of the sodium bicarbonate in subsequent crystallization of sodium carbonate decahydrate. The reduced brine is directed to a crystallizer operated to form pure sodium carbonate decahydrate crystals and a carbonate/bicarbonate containing mother liquor. The mother liquor is then recycled as a portion of said aqueous solvent to be used in the solution mining of the ore deposit.

Abstract: A solution mining process for recovering sodium values from an underground deposit of a sodium bicarbonate containing ore is disclosed. The process involves contacting the ore with an aqueous sodium carbonate-containing solution to produce a dilute brine which is stripped with steam to reduce the bicarbonate content and increase the carbonate content. The dilute carbonate/bicarbonate solution from the stripper is fed to a sodium carbonate decahydrate crystallizer to produce pure sodium carbonate decahydrate crystals and a mother liquor containing less than about 4% sodium bicarbonate.

Abstract: A process for forming useful sodium salts by uniquely processing dilute mine brines obtained by solution mining of a sodium bicarbonate containing ore deposit with an aqueous solvent is disclosed. The dilute mine brine is reduced in sodium bicarbonate content to prevent precipitation of the sodium bicarbonate in subsequent crystallization of sodium carbonate decahydrate. The reduced mine brine is directed to a crystallizer operated to form pure sodium carbonate decahydrate crystals and a carbonate/bicarbonate containing mother liquor in which the bicarbonate content is less than 4.5% by weight. The mother liquor is then steam stripped to convert a portion of the dissolved sodium bicarbonate in the mother liquor to sodium carbonate to form a carbonate enriched brine. The carbonate enriched brine is then recycled as a portion of said aqueous solvent to be used in the solution mining of the ore deposit.

Abstract: A solution mining process for recovering sodium values from an underground deposit of a sodium bicarbonate containing ore is disclosed. The process involves contacting the ore with an aqueous sodium carbonate-containing solution to produce a dilute brine which is stripped with steam to reduce the bicarbonate content and increase the carbonate content. The dilute carbonate/bicarbonate solution from the stripper is fed to a sodium carbonate decahydrate crystallizer to produce pure sodium carbonate decahydrate crystals and a mother liquor containing less than about 4% sodium bicarbonate.

Abstract: A process for producing sodium carbonate and other sodium-based chemicals from an aqueous solution containing sodium bicarbonate by contacting an aqueous solution of a bicarbonate-containing composition with a gas that is predominately other than carbon dioxide in an amount and for a time adequate to cause a sufficient amount of carbon dioxide to leave the aqueous solution to reduce the amount of bicarbonate ion in the solution by converting the bicarbonate to carbonate as carbon dioxide leaves the solution and thereafter converting the remaining solution to other sodium salts.