A soda ash and sodium bicarbonate production method is provided, in which solution mining, pretreatment, stripping, concentration, sodium carbonate decahydrate crystallization, separation, dissolution, sodium carbonate monohydrate crystallization, separation and drying are performed to obtain dense soda ash. A dissolved sodium carbonate decahydrate solution or a concentrated brine 3 is subjected to crystallization, separation and drying to produce sodium bicarbonate. A discharge liquid 1 generated in the sodium carbonate decahydrate crystallization and separation is subjected to causticization and evaporation to recycle sodium carbonate. Causticized sludge generated in causticization is calcined and then recycled for causticization. The process provided herein maximizes the resource utilization.

A soda ash and sodium bicarbonate production method is provided, in which solution mining, pretreatment, stripping, concentration, sodium carbonate decahydrate crystallization, separation, dissolution, sodium carbonate monohydrate crystallization, separation and drying are performed to obtain dense soda ash. A dissolved sodium carbonate decahydrate solution or a concentrated brine 3 is subjected to crystallization, separation and drying to produce sodium bicarbonate. A discharge liquid 1 generated in the sodium carbonate decahydrate crystallization and separation is subjected to causticization and evaporation to recycle sodium carbonate. Causticized sludge generated in causticization is calcined and then recycled for causticization. The process provided herein maximizes the resource utilization.

A method of forming lithium carbonate from a lithium-bearing solution including:

evaporating the lithium-bearing solution to precipitate a first group of impurities;
removing the first group of impurities to form a first purified solution; and
performing a flash crystallisation step within a predetermined temperature range to crystallise a second group of impurities from the first purified solution;
removing the second group of impurities from the first solution to form a second purified solution, wherein at least 90 wt % of lithium is recovered from the first purified solution; and
reacting the second purified solution with a metal carbonate to form lithium carbonate of at least 90 wt % purity.

A method of forming lithium carbonate from a lithium-bearing solution including:

evaporating the lithium-bearing solution to precipitate a first group of impurities;
removing the first group of impurities to form a first purified solution; and
performing a flash crystallisation step within a predetermined temperature range to crystallise a second group of impurities from the first purified solution;
removing the second group of impurities from the first solution to form a second purified solution, wherein at least 90 wt % of lithium is recovered from the first purified solution; and
reacting the second purified solution with a metal carbonate to form lithium carbonate of at least 90 wt % purity.

The present disclosure relates to the field of resource-oriented utilization technologies for wastewater salt muds and more particular to a resource-oriented utilization method for a high-salt salt mud containing sodium chloride and sodium sulfate. The method includes: performing two stages of oxidation, i.e. Fenton-like treatment and chlorine dioxide treatment, in sequence on a salt mud solution, and then replacing a sodium salt with an ammonium salt to prepare a pure alkali and a mixed ammonium salt. In the method, multi-stage oxidation process is performed to effectively use ingredients such as sodium chloride and sodium sulfate so as to thoroughly eliminate organic matters and heavy metals in the high-salt salt mud, and achieve resource-oriented utilization of the salt mud, thus saving burial treatment costs, and producing good economic benefits as well as good environmental benefits.

The present disclosure relates to the field of resource-oriented utilization technologies for wastewater salt muds and more particular to a resource-oriented utilization method for a high-salt salt mud containing sodium chloride and sodium sulfate. The method includes: performing two stages of oxidation, i.e. Fenton-like treatment and chlorine dioxide treatment, in sequence on a salt mud solution, and then replacing a sodium salt with an ammonium salt to prepare a pure alkali and a mixed ammonium salt. In the method, multi-stage oxidation process is performed to effectively use ingredients such as sodium chloride and sodium sulfate so as to thoroughly eliminate organic matters and heavy metals in the high-salt salt mud, and achieve resource-oriented utilization of the salt mud, thus saving burial treatment costs, and producing good economic benefits as well as good environmental benefits.

A method for dissolving a lithium compound according to the present invention includes bringing a lithium compound into contact with water or an acidic solution, and feeding, separately from the lithium compound, a carbonate ion to the water or the acidic solution to produce carbonic acid, and allowing the carbonic acid to react with the lithium compound to produce lithium hydrogen carbonate.

A method for dissolving a lithium compound according to the present invention includes bringing a lithium compound into contact with water or an acidic solution, and feeding, separately from the lithium compound, a carbonate ion to the water or the acidic solution to produce carbonic acid, and allowing the carbonic acid to react with the lithium compound to produce lithium hydrogen carbonate.

A process for the recovery of lithium carbonate from a solution (1) containing a mixture of lithium sulfate and lithium hydroxide, the process comprising the precipitation of lithium carbonate (3) from the solution (1) containing a mixture of lithium sulfate and lithium hydroxide through the addition of carbon dioxide (2).

A process for the recovery of lithium carbonate from a solution (1) containing a mixture of lithium sulfate and lithium hydroxide, the process comprising the precipitation of lithium carbonate (3) from the solution (1) containing a mixture of lithium sulfate and lithium hydroxide through the addition of carbon dioxide (2).