Pretreatment method of two-stage enhanced coagulation deoiling for coal chemical industry wastewater

Abstract

The invention relates to a pretreatment method of two-stage enhanced coagulation deoiling for coal chemical industry wastewater, comprising the specific steps: (1), first-stage coagulation and bouncing treatment: introducing effluent of an oil separation tank into a first-stage coagulating tank, adding an inorganic polymeric coagulant into the first-stage coagulating tank to form small coagulations, adding an organic polymeric coagulant to enlarge the coagulations, and charging the effluent of the first-stage coagulating tank into a bouncing tank for oil-water separation; (2), second-stage coagulation and gas floatation treatment: introducing effluent of the bouncing tank into a second-stage coagulating tank, adding an inorganic polymeric coagulant and an organic polymeric coagulant successively into the second-stage coagulating tank, charging effluent of the second-stage coagulating tank into a gas flotation tank, and carrying out second-stage enhanced coagulation deoiling treatment by means of gas flotation in the gas flotation tank so that the effluent of the gas flotation tank is lower than 80-100 mg/L and adapts to subsequent biochemical treatment. Compared with the prior art, the method has the advantages such as good deoiling effect, good operation stability and low treatment cost.

Description

technical field [0001] The invention relates to a sewage pretreatment method, in particular to a two-stage enhanced coagulation and oil removal pretreatment method for coal chemical wastewater. Background technique [0002] my country's fresh water resources are poor, and the per capita share is only 1 / 4 of the world average, and the distribution is uneven, especially the reverse distribution of water resources and coal resources. Currently, water resources have become the primary factor affecting the development of my country's coal chemical industry. However, when my country introduces and develops the core technology of coal chemical industry, it often fails to introduce and develop coal chemical wastewater treatment technology in time, and its supporting wastewater treatment technology is backward. [0003] Coal chemical industry wastewater is a kind of high-concentration organic wastewater with extremely complex pollutant components and many refractory substances. It co...

AI Technical Summary

Problems solved by technology

However, the coal chemical industry wastewater contains volatile phenol, ammonia and other substances, which are easily entrained and escaped by the air flotation method, causing adverse effects on the environment

Coal chemical industry wastewater also has a certain amount of dust and viscosity, and the filter method needs to be backwashed, which is complicated to operate

The coarse granulation method also has high requirements on the dust content of wastewater. If the dust content is too high, it will cause material clogging.

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