System for advanced treatment and recycle of cold rolling wastewater

Abstract

The invention relates to a cold rolling waste water advanced treatment reuse system, which comprises a pretreatment process, a biological two-stage treatment process and an electric adsorption desalting treatment process. The pretreatment process comprises a uniformly-adjusting tank, a two-stage pH adjusting groove, a dissolved-air float, a middle pond, a cooling tower, a cooling pond, a plate type heat exchanger and the like. The biological two-stage treatment process comprises a biological contact oxidation pond, an inclined plate settling tank, a membrane biological reaction tank, a reactor, a cleaning box, a suction pump and the like. The electric adsorption desalting treatment process comprises an electric adsorption raw water pool, an electric adsorption moudle, a clean water tank, a reuse water pump, a regeneration pump, a sewage drain pump, an electric adsorption enriched water tank and the like. The cold rolling waste water undergoes the pre-treatment process comprising the uniform aeration adjustment, the two-stage pH adjustment and the dissolved-air flotation, the biological two-stage treatment step provided with the membrane biological reactor for contact oxidation and the electric adsorption deep desalting treatment process, thereby effectively removing pollutants in the cold rolling waste water, reutilizing the cold rolling waste water and achieving the aim of energy conservation and emission reduction.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and in particular relates to an advanced treatment and reuse system for cold rolling waste water in the iron and steel industry. Background technique [0002] The composition of cold rolling wastewater in the iron and steel industry is complex, and the water quality varies greatly. In order to effectively treat cold rolling wastewater, various chemical agents (such as HCl, Ca(OH)2, PAC, etc.) must be added to the process of the treatment system for neutralization, coagulation and precipitation to remove pollutants in the wastewater . In addition, the cold rolling wastewater is doped with a large amount of additives used in the strip rolling process, so that a large number of anions and cations are dissolved in the cold rolling wastewater, and the conductivity of the wastewater is relatively high, with an average conductivity greater than 3000μs / cm. After the subsequent biochemical treat...

AI Technical Summary

Problems solved by technology

At present, the widely used desalination technologies include reverse osmosis, ion exchange, electrodialysis, distillation, etc. The biggest disadvantage of these technologies is that they have high requirements on the quality of influent water, and the quality of discharged water after conventional treatment is far from meeting the requirements of influent water.

If it is applied in the advanced treatment and reuse system of cold rolling wastewater, it will definitely increase the investment cost of pretreatment, increase the operating cost, and bring inconvenience to daily maintenance and operation.

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