Ferric phosphate wastewater treatment process and treatment device

Abstract

The invention discloses a ferric phosphate wastewater treatment process and treatment device, wherein the treatment process comprises the following steps of (1) membrane concentration: ferric phosphate wastewater is subjected to membrane concentration to obtain concentrated water and fresh water, wherein the membrane concentration includes reverse osmosis and / or electroosmosis; (2) evaporation: the concentrated water is evaporated to recycle a nitrogen and phosphorus compound fertilizer; the evaporated concentrated liquid flow backs to the membrane concentration front end for circulation treatment; (3) resin treatment: the fresh water and evaporated condensed liquid are subjected to resin absorption treatment; resin absorption effluent is discharged in a standard reaching way or is reused for production; resin analytical liquid is subjected to membrane concentration treatment. Multistage reverse osmosis and resin absorption treatment are combined; ferric polyphosphate wastewater is subjected to desalination and ammonia and nitrogen removal step by step, so that the insulation capability of the whole treatment process on ammonia and nitrogen is higher; the ammonia and nitrogen discharging standard exceeding of effluent can be effectively avoided.

Description

technical field [0001] The invention relates to the field of industrial wastewater treatment, in particular to a treatment process and a treatment device for iron phosphate wastewater. Background technique [0002] At present, the production process of ferric phosphate is to dissolve polyferric sulfate into a solution with an iron ion concentration of 0.03-0.3M, then add phosphate solution to generate basic ferric phosphate slurry, and then separate the slurry from solid to liquid; Add basic ferric phosphate to phosphoric acid solution for treatment, adjust the pH value, then filter, wash and dry to obtain battery grade ferric phosphate. Since the production process of ferric phosphate is intermittent, the cleaning tank often produces a large amount of cleaning wastewater. The content of ammonia nitrogen in this wastewater is high, and the content of sulfate and total phosphorus is seriously exceeded. It cannot be discharged directly, which will cause environmental water pol...

AI Technical Summary

Problems solved by technology

However, reverse osmosis has a higher rejection rate for phosphate, fluoride, and chloride ions, but a lower rejection rate for ammonium ions or ammonia molecules. Simple reverse osmosis units often have a rejection rate of less than 90% for ammonia nitrogen. Due to reverse osmosis concentration limitation, it is difficult to increase the salinity

[0006] The Chinese patent document with the publication number CN105000635A discloses a treatment method for iron phosphate wastewater. The wastewater undergoes two-stage reverse osmosis to remove part of ammonia nitrogen, sulfate and total phosphorus, and can be used to produce pure water. The result of reverse osmosis is often due to the penetration of ammonia molecules, which cannot completely and effectively block ammonia nitrogen. In the actual process, ammonia nitrogen often exceeds the standard

In this process, because there is no protection of resin, the ammonia nitrogen is easy to exceed the standard, which cannot meet the standard of recycling

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