Steel enterprise cold rolling oily wastewater treatment method

Abstract

The invention discloses a steel enterprise cold rolling oily wastewater treatment method, and belongs to the technical field of industrial wastewater treatment. According to the technical scheme, thick oil wastewater generated in a steel rolling process is treated by a regulating tank, a thick oil pH value regulating tank, a horizontal flow oil separation tank, a thick oil cavitation air floatation tank and a thick oil dissolved air floatation tank in sequence; then the treated thick oil wastewater and thin oil wastewater generated in the steel rolling process are sequentially treated by a thin oil adjusting tank, a thin oil pH value adjusting tank, a two-stage cavitation air floatation tank, a cooling tower, a two-stage dissolved air floatation tank, a hydrolysis acidification tank, an anaerobic tank, a two-stage contact oxidation tank, a secondary sedimentation tank, an advanced oxidation tank and a biological aerated filter, and effluent is discharged to a sewage treatment plant for advanced treatment. The method is low in energy consumption, low in cost, simple in equipment, easy to operate, high in regulation performance and stable in treatment effect, can effectively solve the current water treatment problem of iron and steel enterprises, and has important significance in promoting the iron and steel enterprises to realize energy conservation, emission reduction and green sustainable development.

Description

Technical field[0001]The invention belongs to the technical field of industrial wastewater treatment, and in particular, the present invention relates to a method of cold-rolled oil-containing wastewater treatment in steel enterprises.Background technique[0002]A large amount of oil-containing wastewater is generated during the rolling process of steel enterprise cold-rolled sheets, and there are three ways to eliminate cold rolling during the rolling process, which is required to cool and lubricate emulsion (this part of emulsification) The liquid is mainly composed of mineral oil, vegetable oil, animal oil, anionic or nonionic emulsion and water), thereby producing cold rolled emulsion wastewater; 2 cold rolling in loose roll, with an alkaline solution before annealing, The alkaline-containing oil-containing wastewater produced; 3 oil-containing fat-containing wastewater discharged in other production processes. These wastewater have the highest oil content of 50 g / L, and the COD...

AI Technical Summary

Problems solved by technology

However, as the country has increasingly stringently regulated the pollutant discharge indicators of iron and steel enterprises, it has been found in daily operation that the operating costs of the existing process are extremely high. At the same time, the treated effluent can no longer meet the current pollutant discharge standards of the iron and steel industry, and internal reuse will also exist. Many bottlenecks such as the water quality of the pollution system have seriously restricted the production and sustainable development of high-quality products of iron and steel enterprises

[0003] At present, in the daily use of the process, the cost of the titanium alloy electrode plate used in the electrocatalytic oxidation, the ultrafiltration membrane used in ultrafiltration, and the nanofiltration membrane used in nanofiltration are extremely high, and the operation of these equipment is difficult due to the characteristics of the treated wastewater. The service life is less than 3 years, and the replacement cost becomes a financial burden for the enterprise. At the same time, the water quality cannot be stabilized at the end of the equipment life, causing hidden dangers of water quality fluctuations

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