Ammonia chloride waste water zero release treating process

Abstract

The invention relates to a zero-discharge treatment process for ammonium chloride wastewater. The specific method is as follows: (1) ammonium chloride solution enters a pretreatment device to make the treated water quality SDI<3 and turbidity<0.1NTU. (2) Enter the multi-stage multi-stage reverse osmosis membrane group. The concentration of ammonium chloride in the concentrated water treated by the reverse osmosis membrane group can reach 5-8%. (3) The concentrated effluent from the reverse osmosis device enters the distillation evaporation device and is further concentrated to an ammonium chloride concentration of 36-45%. (4) Further concentrate the processed ammonium chloride concentrate, and go to the crystallization device for cooling and crystallization to produce ammonium chloride. The crystallization mother liquor is returned to the evaporation device after being treated by decalcification and magnesium devices, and enters the evaporation device circulation together with the concentrated effluent of the reverse osmosis membrane group concentrate. The invention not only can meet the requirement of zero discharge of ammonium chloride wastewater, but also can obtain two kinds of products, ammonium chloride crystal and process fresh water, and can treat the wastewater with ammonium chloride content ranging from 500mg / L to 200000mg / L.

Description

technical field [0001] The invention belongs to the technical field of three wastes, and in particular relates to a zero-discharge treatment process of ammonium chloride wastewater. Background technique [0002] The direct discharge of ammonium-containing wastewater generated in the production process of chemical fertilizers, soda ash, catalysts, etc. will greatly increase the eutrophication of the recipient water source and seriously pollute the environment. At the same time, direct discharge is also a serious waste of resources, so the ammonium-containing wastewater is treated and utilized Realizing zero discharge of wastewater is of great significance to environmental protection and resource utilization. [0003] For the treatment of ammonium chloride wastewater, the main process methods are physical method and chemical method. Physical methods include ion exchange, ammonia stripping, steam stripping, multiple-effect evaporation, and electro...

AI Technical Summary

Problems solved by technology

Electrodialysis is suitable for the treatment of 1000mg / L-5000mg / L wastewater containing ammonium ions. If it exceeds this concentration range, the efficiency will be low and the energy consumption will increase sharply.

[0012] In the chemical method, the treatment effect of the biochemical method is stable and the operating cost is low, but if the concentration of ammonium chloride wastewater is high, exceeding 10,000mg / L, the bacteria will not survive, and the biochemical treatment will not be possible; adding alkali (or quicklime) Although the process of concentrating and recovering ammonia can adapt to various concentrations of ammonium chloride wastewater, there are problems such as high consumption, incomplete reaction and secondary pollution.

Images