How to use industrial grade sodium metabisulfite in sewage treatment

Sodium metabisulfite can be divided into industrial grade sodium metabisulfite and food grade sodium metabisulfite according to product types and different uses. Sodium metabisulfite has applications in many aspects and also plays an important role in industrial wastewater treatment. So sodium metabisulfite plays a specific role in industrial wastewater treatment. What is the effect?

　　Sodium metabisulfite plays an important role in the treatment of industrial wastewater. Sodium metabisulfite is a reducing agent and is used to treat chromium-containing wastewater in wastewater treatment. China's chromium-containing wastewater requires separate treatment and cannot be discharged into a comprehensive pool, and the concentration of hexavalent chromium cannot be higher than 0.1. Therefore, the delivery point of sodium metabisulfite is in the raw water of chromium-containing wastewater, reducing hexavalent chromium to trivalent chromium, and then Perform precipitation. Wastewater treatment Sodium metabisulfite is a white or yellowish powder. It has a reducing effect under acidic conditions, but it does not remove heavy metals. The use of sodium sulfide and sodium metabisulfite is generally used for wastewater treatment in the electroplating industry. For example, for the treatment of hexavalent chromium wastewater, sodium metabisulfite can be added first, let them pass through a sufficient reduction reaction, then adjust the alkali to add other products, and then add sulfide Sodium to remove heavy metals that have not completed precipitation. This is the important role of sodium metabisulfite in the treatment of industrial wastewater.

       Sodium metabisulfite acts as a reducing agent and can treat chromium-containing wastewater in anhydrous treatment.

       The main pollution component of chromium-containing wastewater is hexavalent chromium ions, and the source is mainly chromium-containing ore processing, metal surface treatment, printing and other industries. Hexavalent chromium ions are harmful to the environment.

Generally, adjust anhydrous water to pH value between 2~3, and then add sodium metabisulfite to reduce hexavalent chromium ions to trivalent chromium ions, and then adjust water to pH 8~9, in the solution The trivalent chromium ions will generate chromium hydroxide precipitation, and the precipitation will be processed.