Processes and apparatus for purifying brine are provided including (1) providing an aqueous brine solution comprising one or more inorganic salts and one or more organic compounds and (2) conducting at least one unit operation for removing organic compounds from the brine solution to obtain a purified brine solution.

Processes and apparatus for purifying brine are provided including (1) providing an aqueous brine solution comprising one or more inorganic salts and one or more organic compounds and (2) conducting at least one unit operation for removing organic compounds from the brine solution to obtain a purified brine solution.

The invention includes methods of removing particulate matter from potash tailings fluid comprising providing an activating material capable of being affixed to the particulate matter, affixing the activating material to the particulate matter to form an activated particle, providing an anchor particle and a tethering material capable of being affixed to the anchor particle; and attaching the tethering material to the anchor particle and the activated particle to form a removable complex in the potash tailings fluid. The invention also includes providing an activating material capable of being affixed to the particulate matter in the potash tailings fluid; affixing the activating material to the particulate matter to form an activated particle; providing an anchor particle and enveloping it with an enveloping agent to form an enveloped anchor particle capable of attaching to the activated particle; and combining the enveloped anchor particle with the activated particle to form a removable complex.

The invention includes methods of removing particulate matter from potash tailings fluid comprising providing an activating material capable of being affixed to the particulate matter, affixing the activating material to the particulate matter to form an activated particle, providing an anchor particle and a tethering material capable of being affixed to the anchor particle; and attaching the tethering material to the anchor particle and the activated particle to form a removable complex in the potash tailings fluid. The invention also includes providing an activating material capable of being affixed to the particulate matter in the potash tailings fluid; affixing the activating material to the particulate matter to form an activated particle; providing an anchor particle and enveloping it with an enveloping agent to form an enveloped anchor particle capable of attaching to the activated particle; and combining the enveloped anchor particle with the activated particle to form a removable complex.

Described herein is a 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.

Described herein is a 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.

A process for the preparation of purified potassium chloride comprises the at least partial removal of one or more class 1 heavy metal impurity (lead, arsenic, cadmium and/or mercury) from potassium chloride process liquor by an ion exchange step. The process uses an ion exchange resin and achieves high levels of purity and is compatible with high flow rates. A recrystallisation step (e.g. a cooling crystallization step) may be employed subsequent to the ion exchange step.

A multi-pond system and method is disclosed for separating sodium carbonate from sodium chloride in process purge streams from soda ash production or similar facilities. The system comprises a first pond, exposed to atmospheric environment, for receiving the process purge stream and allowing deposition of sodium carbonate in accord with phase chemistry as water is evaporated and temperatures change thereby creating a liquor with increased sodium chloride concentration. A second pond for receiving the first pond liquor, exposed to the atmospheric environment, and allowing deposition of sodium chloride in accord with phase chemistry as water evaporates and temperatures change thereby creating a second pond liquor with increased sodium carbonate concentration. Alternatively transferring at least a portion of the second pond liquor back to the first pond or into an optional third pond.

A multi-pond system and method is disclosed for separating sodium carbonate from sodium chloride in process purge streams from soda ash production or similar facilities. The system comprises a first pond, exposed to atmospheric environment, for receiving the process purge stream and allowing deposition of sodium carbonate in accord with phase chemistry as water is evaporated and temperatures change thereby creating a liquor with increased sodium chloride concentration. A second pond for receiving the first pond liquor, exposed to the atmospheric environment, and allowing deposition of sodium chloride in accord with phase chemistry as water evaporates and temperatures change thereby creating a second pond liquor with increased sodium carbonate concentration. Alternatively transferring at least a portion of the second pond liquor back to the first pond or into an optional third pond.