A waste liquid treatment and recovery system for stainless steel pickling line

Abstract

The invention discloses a waste liquid treatment recycling system of a stainless steel pickling line. The waste liquid treatment recycling system mainly comprises a regulating reservoir, a precision filter, a neutralizing oxidation pond, an oblique pipe precipitation pond, a sludge concentration pond, a sludge storage pond, an air floatation pond, a press filter, a medium filter, an active carbon filter and a clean water pond, and is characterized in that pickling waste water flows into the regulating reservoir, the regulating reservoir is connected with the precision filter, the precision filter is connected with the neutralizing oxidation pond, the neutralizing oxidation pond is connected with the oblique pipe precipitation pond, the oblique pipe precipitation pond is connected with the sludge concentration pond, the sludge concentration pond is connected with the sludge storage pond, the sludge storage pond extends in two circuits, one circuit is connected to an external mud cake transport device by virtue of the press filter, and the other circuit is connected to a clean water discharge pipe sequentially by virtue of the air floatation pond, the medium filter, the active carbon filter and the clean water pond.

Description

technical field [0001] The invention relates to the field of pickling wastewater treatment, in particular to a waste liquid treatment and recovery system for a stainless steel pickling line. Background technique [0002] In the manufacture of stainless steel, in order to remove the scale on the surface of the steel after annealing, a mixed acid made of nitric acid and hydrofluoric acid is generally used for surface cleaning, which is called pickling. With the development of the iron and steel industry and the surface treatment industry, the annual production of pickling waste liquid in the country exceeds one million cubic meters, and its pollution hazard is obvious. The main hazard of acid-containing wastewater is to corrode hydraulic structures such as sewer pipes and reinforced concrete. Acid-containing wastewater seeps into the soil. After a long time, it will cause soil calcification and damage the loose state of the soil layer, thus affecting the growth of crops; acid-...

AI Technical Summary

Problems solved by technology

The main hazard of acid-containing wastewater is to corrode hydraulic structures such as sewer pipes and reinforced concrete. Acid-containing wastewater seeps into the soil. After a long time, it will cause soil calcification and damage the loose state of the soil layer, thus affecting the growth of crops; acid-containing wastewater is discharged into the water body When the oxygen is taken away from the water, the living conditions of the fish and the self-purifying microorganisms participating in the self-purification of the water are destroyed, causing the death of the fish; the pickling wastewater contains heavy metals such as chromium, and excessive chromium is human carcinogenic

[0003] The traditional treatment of pickling wastewater is generally treated by lime neutralization and precipitation. The disadvantages of this treatment process are: 1. For wastewater with high chromium and fluorine content, it generally cannot meet the discharge standard through primary neutralization and sedimentation treatment; 2 Cannot effectively recycle pickling wastewater, which is a great waste of resources

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