What is sodium bisulfite known as in water treatment?

Sodium bisulfite is primarily known as a dechlorinator in water treatment processes. Its main function is to remove chlorine from water by chemically reacting with it to produce chloride ions, which are less harmful and more stable. This ability to neutralize chlorine is crucial in wastewater treatment as chlorine can be toxic to aquatic life if the treated water is discharged into natural water bodies.

In many treatment processes, chlorine is used for disinfection; however, before releasing treated water into the environment, it's essential to ensure that any residual chlorine is eliminated to protect aquatic ecosystems. Sodium bisulfite is commonly applied because it effectively reduces chlorine levels quickly and is relatively safe to use.

While other chemicals have important roles in water treatment, such as oxidizers that promote reactions with pollutants and flocculants that aid in the aggregation of suspended solids for easier removal, sodium bisulfite’s unique and vital function is specifically that of a dechlorinator, highlighting its importance in the safe treatment and release of water.