Evaporation mother liquor treatment system and process

Abstract

The invention discloses an evaporation mother liquor treatment system and process. A hardness and impurity removal unit of the system carries out purification pretreatment on received evaporation mother liquor; the first dilution unit is used for diluting the evaporation mother liquor subjected to purification pretreatment; the filtering unit is used for filtering the evaporation mother liquor diluted by the first diluting unit; the nanofiltration membrane concentration unit is used for separating monovalent salt and divalent salt from the received evaporation mother liquor; the nanofiltration concentrated water tank is used for caching concentrated water of the nanofiltration membrane concentration unit; the freezing and recrystallizing unit is used for freezing and recrystallizing concentrated water in the nanofiltration concentrated water tank; the nanofiltration water production tank is used for caching water produced by the nanofiltration membrane concentration unit; the evaporative crystallization unit is used for performing evaporative crystallization on the received produced water of the nanofiltration produced water tank; the second dilution unit is used for diluting the received concentrated solution of the evaporative crystallization unit, and the selective membrane salt separation unit is used for carrying out monovalent salt separation on the received diluted solution of the second dilution unit. The method is wider in applicability and stable in performance; the evaporation mother liquor can be effectively treated, carnallite recycling is achieved, and the treatment cost is reduced.

Description

technical field [0001] The invention relates to an evaporation mother liquor treatment system and process, and belongs to the technical field of water treatment. Background technique [0002] In recent years, zero discharge of water treatment has become the general trend, and industries such as coal chemical industry, power plants, and mine water have begun to implement zero discharge of sewage. In the zero-emission project, the evaporation process is indispensable, and a large amount of evaporation mother liquor will be produced during the evaporation process. The main components of the evaporation mother liquor are the mixed solution of sodium nitrate, sodium chloride and sodium sulfate. [0003] Common evaporative mother liquor treatment methods include: sending the evaporating mother liquor to a professional mother liquor treatment center, or adding a solidifying agent (lime, etc.) to the evaporating mother liquor to solidify and then landfill as hazardous waste; there a...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the deficiencies in the prior art, the present invention provides an evaporation mother liquor treatment system and process, which solves the problem of high cost and difficulty in traditional evaporation mother liquor treatment, and the inability to realize resourceful treatment of miscellaneous salts

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