Which chemical is commonly used for disinfection in wastewater treatment?

Chlorine is widely used for disinfection in wastewater treatment due to its effectiveness in eliminating harmful pathogens, such as bacteria and viruses, from water before it is released back into the environment or reused. As a strong oxidizing agent, chlorine reacts with microorganisms, disrupting their cellular processes and leading to their inactivation or death. This method of disinfection is not only efficient but also relatively inexpensive, making it a popular choice in various treatment facilities.

While sodium chloride can be involved in some water treatment processes, it is primarily used for saltwater systems and has limited disinfectant properties compared to chlorine. Hydrochloric acid is mainly utilized for pH adjustment and not for disinfection, as it does not possess antimicrobial activity. Calcium carbonate, on the other hand, serves crucial roles in alkalinity adjustment and hardness stabilization but is not employed as a disinfectant. Hence, chlorine remains a fundamental chemical in the sanitation of wastewater.