Dechlorination

The practice of removing all or a controlled part of a total combined chlorine residual in water or wastewater. Dechlorination is normally accomplished through the measured injection of sulfur dioxide, utilizing a sulfonator device.

Sulfur dioxide reacts with chlorine to form hydrochloric acid, thereby removing chlorine. The amount of hydrochloric acid formed is minimal, and has very little effect on the pH of the discharged wastewater.