Application of caustic soda in industrial wastewater treatment

The flake Caustic Soda for industrial sewage treatment, because Caustic Soda mainly contains hydroxide OH- and sodium ion Na+, and the hydroxide can combine with a variety of metal ions to form flocs or precipitates. For example, the sewage contains aluminum ions (Al3+) Or metal ions such as iron ions (Fe3+, Fe2+), weak acid salts and strong acid salts, react with OH- ions in Caustic Soda to produce flocs or insoluble precipitates Fe3+ + 3OH- = Fe(OH)3, Al3+ + 3OH- = Al(OH)3.

The main content of Polyaluminum Chloride is Al2O3, and its flocculation principle is mainly combined with hydroxide OH- in wastewater to form Al(OH)3 flocculent material, which can achieve flocculation effect. Caustic soda can also remove excess acid ions in industrial wastewater, such as Cl-, (SO4)2-, (PO4)3-, etc., caustic soda NaOH is also commonly used to adjust the pH value, according to the PH situation to determine the amount of sodium hydroxide. 

In sewage treatment plants,Caustic Soda can reduce the hardness of water by neutralization. In the industrial field, it is a regenerant for ion exchange resin regeneration.

Caustic soda is strongly alkaline and has a relatively high solubility in water.

Caustic soda is currently used in water treatment for the following problems: elimination of water hardness; adjustment of water pH; neutralization of wastewater; regeneration of ion exchange resin; elimination of heavy metal ions in water by precipitation.