Dithiophosphate wastewater pretreatment method

Abstract

The invention discloses a dithiophosphate wastewater pretreatment method. Dithiophosphate wastewater is pretreated by the three steps of stream stripping, electro-catalytic reaction and coagulation to remove ammonia nitrogen from the wastewater, and is supplied to a biochemical system for treatment after reaching biochemical treatment requirements when effluent is colorless and odorless, the CODcr is reduced to be lower than 10,000 mg / L, the biodegradability B / C of the wastewater is more than 0.3, the chromaticity is less than 50 and the ammonia nitrogen is reduced to be lower than 15 mg / L. According to the method, the three treatment steps of stream stripping, electrolysis and coagulation are combined, so that the problems of high ammonia nitrogen, high COD and stink in the dithiophosphate wastewater are solved, and the ammonia nitrogen in the wastewater is effectively recycled for production; the method has the characteristics of high impact load resistance, good treatment effects and lower running cost, certain economic benefits can also be created, and the stink of the dithiophosphate wastewater can be completely prevented to meet the biochemical treatment requirements after the dithiophosphate wastewater is treated.

Description

technical field [0001] The invention relates to a pretreatment method for waste water with high ammonia nitrogen, bad smell, refractory degradation and refractory biochemical treatment produced in the production process of the pesticide dimethoate intermediate. Background technique [0002] Phospholipid is an intermediate of the pesticide dimethoate. The concentration of CODcr and ammonia nitrogen in the wastewater generated during the production process is as high as 70000 mg / L and 64000 mg / L respectively, which has high concentration of organic pollutants, high concentration of ammonia nitrogen, stench, Refractory to degradation, difficult to biochemical treatment and other characteristics. The main organic pollutants in the wastewater are phosphorothioate, phosphorothioate, phosphoric acid, mercapto compounds, disulfide compounds, etc. These pollutants are the cause of its stench and high COD. [0003] At present, the pretreatment methods for this type of wastewater gene...

AI Technical Summary

Problems solved by technology

The wet oxidation method has not been widely promoted because of its high requirements on equipment materials. The application of ozone oxidation technology is also limited due to reasons such as large equipment investment, low ozone utilization rate, and excessive ozone is easy to corrode pipeline equipment.

The Fenton method and its improved technology require a large dosage of reagents and high costs, and cannot solve the problem of the foul smell of phosphorothioate wastewater, nor can it reduce the concentration of high ammonia nitrogen in wastewater

Although the complexation of copper ions can effectively solve the stench of phosphorothioate pollutants, it is not suitable for long-term large-scale use because the cost of copper salts is too high and it is easy to cause copper ion pollution.

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