Treatment of Wastewater from Metal Surface

The treatment processes of sulfuric acid washing liquor in iron and steel industry mainly include neutralization, ferric sulfate, organic solution extraction, dialysis, ion exchange and so on. The latter three methods are still in the experimental research stage, and the industrial application is mostly the production of ferrous sulfate, polyferric sulfate and pigments by ferric sulfate method.

1. Neutralization

2. Ferric sulfate process 3. Diffusion dialysis-diaphragm electrolysis

4. Ferric oxide red ammonium sulfate method

5. Wetland Method

6. Biological method