Process for treating saponification wastewater by chlorohydrination

Abstract

The invention discloses a chemical processing method, and in particular discloses a method for recovering and reusing saponified waste water generated by a chlorohydrination method. The invention uses the novel film method and the salt and water recovering and reusing method to process the saponified waste water generated by a chlorohydrination method, and the technical designs, such as gas flotation, crystallizing prevention, ceramic film filtration, heat exchange, electrodialysis concentration, vaporizing recovery and the like are applied in the method. The invention has the advantages thatthe zero discharge of the waste water is basically realized, the salt and the water can be recovered, the small land area is occupied, the running expense is low, and the economic and social benefitsare high. The invention can be widely used in the factories using the chlorohydrination method for producing propylene oxide.

Description

technical field

[0001] The invention relates to a chemical treatment method, in particular to a treatment method for recycling saponification wastewater produced by chlorohydrinization. Background technique

[0002] Through technical novelty research, the current domestic methods of treating this type of wastewater mainly include direct discharge to urban sewage treatment plants for unified treatment, biological methods and physical, physical and chemical combination processes, etc.

[0003] The production of propylene oxide is mainly divided into two steps. The first step is chloroalcoholization, which requires a large amount of fresh water; the second step is saponification reaction. The saponification wastewater of chlorohydrinization method mainly comes from the saponification reaction process. A large amount of sewage discharged from the saponification process in the process of producing epoxides by the chlorohydrin method, due to the high salt concentration (CaCl 2 Th...

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