| 摘要 |
A method of producing crystals of crystallizable mineral salt comprises introducing an effluent comprising a dissolved crystallizable mineral salt at a temperature higher than the mineral salt crystallization temperature to a crystallization pond area to provide a pond solution; cooling the pond solution to provide cooling crystallization promoting conditions effective to form a crystalline mineral salt deposit; stopping the flow of the effluent; draining remaining spent liquor to a liquor pond area; and recovering the deposit. Cooling the pond solution may comprise exposure to cool ambient temperatures which are lower than the crystallization temperature. Preferably, the mineral salt includes or is sodium carbonate decahydrate; the pond solution comprises less than 10% NaCl; and/or the decahydrate deposit is sent or recycled to a soda ash plant. The deposit thus formed by cooling crystallization has a higher purity, lower hardness, and/or lower density than a deposit formed by evaporative crystallization.
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