Steel pickling waste water treating process

Abstract

The invention provides a steel pickling waste water treating process. The steel pickling waste water treating process comprises the following steps that firstly, after flow of steel pickling waste water is adjusted by a flow adjusting pool, the steel pickling waste water enters a public security filter, is primarily filtered and then enters an ultrafiltration membrane assembly to be subjected to ultrafiltration membrane filtration; secondly, the steel pickling waste water filtered through an ultrafiltration membrane is pumped to a first-level reverse osmosis water tank and a second-level reverse osmosis water tank through a first pressurizing pump to be subjected to reverse osmosis filtering treatment, and water out of the second-level reverse osmosis water tank enters a clean water pool; thirdly, a high-concentration salt solution in the first-level reverse osmosis water tank and a high-concentration salt solution in the second-level reverse osmosis water tank are fed into a neutralization reaction pool; fourthly, a neutralization agent is thrown into the reduction reaction pool to adjust PH; fifthly, the high-concentration salt solution subjected to neutralization treatment is fed into a negative electrode groove of a diaphragm electrolytic cell. Harmless treatment of the steel pickling waste water is achieved, iron powder and pickling liquid can be recovered, resources are saved, and the production cost is reduced.

Description

technical field [0001] The invention belongs to the field of iron and steel processing production, and in particular relates to a treatment process for iron and steel pickling wastewater. Background technique [0002] Stainless steel is widely used because of its excellent, welded corrosion resistance and good appearance. In the production process of stainless steel, it is inevitable to go through annealing, normalizing, quenching and other processing processes, and black oxide scales often appear on the surface. Oxide scale not only affects the appearance quality of stainless steel, but also has an adverse effect on the subsequent processing of the product, so it must be removed by surface treatment methods such as pickling and polishing before subsequent processing. The main hazard of pickling wastewater is to corrode hydraulic structures such as sewer pipes and reinforced concrete. Acidic wastewater infiltrates into the soil, which will cause soil calcification after a ...

AI Technical Summary

Problems solved by technology

This method will generate a large amount of sludge, and the sludge must be treated, and it cannot be recycled and reused, resulting in a waste of resources