Electro-deionization method and electro-deionization device for recycling ammonia nitrogen waste water

Abstract

The invention discloses an electro-deionization method and an electro-deionization method for recycling ammonia nitrogen waste water, wherein the electro-deionization method comprises the following steps: a plurality of modules which are connected in series or in parallel are selected to form a set of electro-deionization device according to the water quantity of waste water to be processed and the mass concentration of ammonium salt of the waste water, wherein inlet water of the device is ammonia nitrogen waste water that is preprocessed and accordant with requirements, producing water is process pure water, does not contain nitrogen-containing compounds and can be recycled; in addition, ammonium salt thickening solution is obtained by a thick water circulated thickening method, and the mass concentration of the ammonium salt reaches an expected requirement of 1-25 percent; and the thickening solution is evaporated, concentrated and crystallized to obtain the solid ammonia nitrogen product. The invention not only can reach the zero emission requirement of the system, but also simultaneously recycle the ammonium salt thickening solution and the process pure water. The invention hasadvanced process, low cost, low energy consumption and simple operation.

Description

technical field [0001] The technical field of the present invention relates to the recovery of ammonia nitrogen wastewater, in particular to the use of electrodeionization membrane technology to process ammonia nitrogen wastewater produced in chemical fertilizer and chemical industry, recover ammonium salt chemical raw materials and obtain pure water for process, so as to realize zero discharge of wastewater. Background technique [0002] In the production process of chemical fertilizers and chemical enterprises, especially in the production of ammonium chloride, ammonium nitrate, ammonium sulfate and other processes, a large amount of ammonia nitrogen wastewater is generated, which not only wastes chemical raw materials, but also pollutes the environment. This kind of ammonia nitrogen wastewater is acidic and highly corrosive, and it is very difficult to recover it with common treatment methods. The biological oxidation method can only oxidize the ammonia nitrogen in the was...

AI Technical Summary

Problems solved by technology

[0002] In the production process of chemical fertilizers and chemical enterprises, especially in the production of ammonium chloride, ammonium nitrate, ammonium sulfate and other processes, a large amount of ammonia nitrogen wastewater is produced, which not only wastes chemical raw materials, but also pollutes the environment

This kind of ammonia nitrogen wastewater is acidic and highly corrosive, and it is difficult to recover it with common treatment methods. The biological oxidation method can only oxidize the ammonia nitrogen in the wastewater and cannot be recovered at all; the ion exchange method can recover ammonium salts, which requires frequent regeneration; reverse osmosis Membrane technology can separate chemical raw materials in wastewater and produce process water, but the water recovery rate of reverse osmosis treatment is low, and its concentrated water discharge is high. When the concentration of ammonium salt in wastewater is low, multiple sets of reverse osmosis are required. Osmotic membrane treatment can recover the ammonium salt in ammonia nitrogen wastewater, which greatly increases the cost of wastewater treatment

Electrodialysis can also recycle waste water, but when dealing with low-concentration waste water, it is easy to produce concentration polarization, which greatly increases power consumption and increases operating costs

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