What is the most common type of chlorine used in water treatment?

Sodium hypochlorite is widely recognized as one of the most common forms of chlorine used in water treatment. This compound is favored due to its effectiveness as a disinfectant and its ability to be easily handled and stored as a liquid solution. Sodium hypochlorite acts by releasing chlorine in water, which helps to eliminate bacteria, viruses, and other pathogens, ensuring safe drinking water.

In many small to medium-scale water treatment facilities, sodium hypochlorite is preferred because of its safety profile compared to chlorine gas, which is a more hazardous substance requiring stringent safety measures. The flexibility of sodium hypochlorite allows for its use across a variety of applications, from municipal water systems to swimming pools, making it a versatile choice for chlorination processes.

While calcium hypochlorite is also used in some water treatment scenarios, particularly in tablet or granular form, sodium hypochlorite remains the most prevalent due to its accessibility and ease of use. Bromine is less commonly used in water treatment; it has specific applications, mainly in pool sanitation, but is not as widely utilized for municipal water disinfection compared to the chlorine compounds.