Hydrochloric acid is also used in demineralization units. Surface water and wastewater Ferric chloride allows flocculation of suspended organic matter as well as the neutralization of the excessive phosphate responsible for the eutrophication of rivers. Calcium chloride is used to purify the water of excess fluorides and is one of the most effective reagents for eliminating sulfates. Hydrogen peroxide , a source of active oxygen, serves to oxygenate surface waters or to treat certain cases of serious pollution. It is also used for detoxifying, deodorizing and bleaching waste waters.
Hydrochloric acid is used in the physico-chemical purification of waste waters.
As for caustic soda, it corrects the pH of acid effluents before disposal into sewers. Sodium hypochlorite, with its long-lasting bactericidal action, makes swimming pool water pure and sparklingly clear. In Scandinavian countries, where the lakes are polluted by acid rain, the immersion of sodium carbonate briquettes neutralizes the water, helping to restore aquatic flora and fauna. Solvay S.A. Updated 2 July 2001. If you have any comments on this Website, please contact the Webmaster .