A method of concentrating lithium containing solutions includes inputting a feed brine solution to an initial separation stage, the feed brine solution including lithium sulfate and one or more of sodium sulfate, potassium sulfate, calcium sulfate, and sodium chloride dissolved in water. In the initial separation stage, the feed brine solution is introduced to a pre-treatment membrane at a pressure that is less than the osmotic pressure of the feed brine solution. An initial permeate that passes through the pre-treatment membrane becomes the feed to a final separation stage, and an initial retentate that does not pass through the pre-treatment membrane includes a precipitate of at least one of the salts other than lithium sulfate. In the final separation stage, the initial permeate is introduced to a nanofiltration membrane at a pressure that is less than the osmotic pressure of the initial permeate. A final retentate that does not pass through the nanofiltration membrane is combined with the initial retentate to obtain a product solution having a higher concentration of dissolved lithium sulfate than the feed brine solution.

Zero liquid discharge systems, processes, and techniques for treating a saltwater without evaporative crystallization. The saltwater is treated by a fluidic circuit comprising a high-pressure reverse osmosis (“HPRO”) unit configured to operate at a hydraulic pressure of at least 1,500 psi, a cooling crystallizer, and a solids-liquid separator. The saltwater is first concentrated by the HPRO unit to produce an HPRO brine, which is subsequently cooled to a designated crystallization temperature by the cooling crystallizer. The cooling crystallizer crystallizes salt crystals from the cooled HPRO brine and produces a salt-diminished brine. The solids-liquid separator separates the salt-diminished brine from the salt crystals. The salt-diminished brine from the solids-liquid separator is returned to the HPRO unit for further treatment, which allows additional salts to be crystallized from the returned salt-diminished brine.

A method for forming an insoluble adduct using an acidic medium is provided. A chemical process utilizes acidic media to change the solubility behavior of metal solutes. The method can utilize Group 1 soluble alkali metals but can also be extended to any other soluble salts discussed under the solubility rules. The insoluble salts can be Group 2 alkaline earth metals or other insoluble salts. The insoluble adduct can have the designation XYZ where X is a soluble metal from a metal hydroxide or a metal oxide, Y is an insoluble metal from an insoluble metal hydroxide or an insoluble metal oxide, and Z is the acid ion from an aqueous acidic media.

A method for forming an insoluble adduct using an acidic medium is provided. A chemical process utilizes acidic media to change the solubility behavior of metal solutes. The method can utilize Group 1 soluble alkali metals but can also be extended to any other soluble salts discussed under the solubility rules. The insoluble salts can be Group 2 alkaline earth metals or other insoluble salts. The insoluble adduct can have the designation XYZ where X is a soluble metal from a metal hydroxide or a metal oxide, Y is an insoluble metal from an insoluble metal hydroxide or an insoluble metal oxide, and Z is the acid ion from an aqueous acidic media.

The invention relates to a process for selective flotation of kainite from crushed crude potash salts or, for example, from crystallized salt mixtures obtained by evaporation processes, which in addition to kainite may contain further minerals such as halite, sylvine and other salt minerals, for example, in order to produce a kainite concentrate fraction and a residues fraction. The separation process is characterized in that the crushed or crystallized salt mixture is intensively mixed as a crystallizate suspension with a combination of conditioning agents consisting of a sulfated fatty acid or its alkali metal salt as collecting reagent and a frothing agent known for flotation (for example, glycol ether, monohydric aliphatic alcohols, terpene alcohols, polyglycol ethers, etc.) and is then separated by agitator-driven or pneumatic flotation into a kainite concentrate fraction and a residues fraction. The resulting fractions may be further processed in downstream processes. This process permits industrial-scale processing for selective extraction of kainite from mineral mixtures by means of the flotation process.

The invention relates to a process for selective flotation of kainite from crushed crude potash salts or, for example, from crystallized salt mixtures obtained by evaporation processes, which in addition to kainite may contain further minerals such as halite, sylvine and other salt minerals, for example, in order to produce a kainite concentrate fraction and a residues fraction. The separation process is characterized in that the crushed or crystallized salt mixture is intensively mixed as a crystallizate suspension with a combination of conditioning agents consisting of a sulfated fatty acid or its alkali metal salt as collecting reagent and a frothing agent known for flotation (for example, glycol ether, monohydric aliphatic alcohols, terpene alcohols, polyglycol ethers, etc.) and is then separated by agitator-driven or pneumatic flotation into a kainite concentrate fraction and a residues fraction. The resulting fractions may be further processed in downstream processes. This process permits industrial-scale processing for selective extraction of kainite from mineral mixtures by means of the flotation process.

A hydrometallurgical process for the treatment of polymetallic ores and sulphide concentrates of copper and zinc, and by-products of lead and zinc from smelting plants, treated independently and/or as mixtures thereof, which contain relevant amounts of lead, copper, zinc, iron, gold and silver, such as the matte-speiss mixture of lead foundries, and copper cements from the purification processes of electrolytic zinc plants. Thee process allows the recovery of metallic copper, zinc, copper as copper and zinc basic salts, which may be hydroxides, carbonates, hidroxysulphates or mixtures thereof; the production of stable arsenic residues; and the effective and efficient recovery of Pb, Au and Ag as a concentrate of lead sulphide and/or lead, Au, and Ag sulphate.

The present disclosure relates to processes for treating an aqueous composition comprising lithium sulfate and sulfuric acid. The processes comprise evaporatively crystallizing the aqueous composition comprising lithium sulfate and sulfuric acid under conditions to obtain crystals of lithium sulfate monohydrate and a lithium sulfate-reduced solution; and optionally separating the crystals of the lithium sulfate monohydrate from the lithium sulfate-reduced solution. The processes optionally further comprise concentrating the lithium sulfate-reduced solution under conditions to obtain an acidic condensate and a concentrate comprising sulfuric acid.

Process for upgrading effluent treatment plants for pulp and paper production processes, where salts are removed from the effluent for water reuse and chemical recovery. The process comprises a first dialysis system for salt removal, a second treatment system for recovery or re-concentration, and optionally a post-treatment of the re-concentrate preventing liquid discharges to the environment. In the first system, a reversible electrodialysis or reversible pulsed step is carried out, separating the salts from the effluent, which are sent to the second treatment system to concentrate the salts (re-concentrate) or transform them into useful chemicals for the same process (recovery). Chemical recovery is achieved by electrodialysis with bipolar membranes or metathesis, to reduce the re-concentrate stream, which cannot be reused in the same plant. Lastly, this stream may be treated by spray drying, crystallization or evaporation.

Process for upgrading effluent treatment plants for pulp and paper production processes, where salts are removed from the effluent for water reuse and chemical recovery. The process comprises a first dialysis system for salt removal, a second treatment system for recovery or re-concentration, and optionally a post-treatment of the re-concentrate preventing liquid discharges to the environment. In the first system, a reversible electrodialysis or reversible pulsed step is carried out, separating the salts from the effluent, which are sent to the second treatment system to concentrate the salts (re-concentrate) or transform them into useful chemicals for the same process (recovery). Chemical recovery is achieved by electrodialysis with bipolar membranes or metathesis, to reduce the re-concentrate stream, which cannot be reused in the same plant. Lastly, this stream may be treated by spray drying, crystallization or evaporation.