Chlorination is a widely used method for water disinfection. It involves adding chlorine-based chemicals, such as chlorine gas or sodium hypochlorite, to water. Chlorine acts as a powerful disinfectant, killing a wide range of bacteria, viruses, and other microorganisms. It can be applied at different stages of the water treatment process, including during pre-treatment, primary disinfection, and residual disinfection to maintain water quality throughout the distribution system.