Which method is most commonly used to disinfect water in large-scale treatment systems?

Chlorination is the most commonly used method for disinfecting water in large-scale treatment systems due to its effectiveness, cost-efficiency, and residual disinfection properties. Chlorine is a powerful disinfectant that kills a wide range of pathogens, including bacteria, viruses, and protozoa, which are common contaminants in water supplies.

One advantage of chlorination is that it creates a residual effect, meaning that chlorine remains in the water as it travels through the distribution system. This residual helps protect against any recontamination that might occur after treatment and before the water reaches consumers. Additionally, the infrastructure to implement chlorination is well-established and widely understood, making it a preferred choice among treatment plants.

While other methods such as ozonation and UV irradiation are also effective, they often lack the residual effect of chlorine, which can make them less practical for large systems needing long-term protection against microbial growth. Ozonation, for instance, requires close monitoring and does not provide any residual disinfection, which could lead to potential regrowth of microorganisms if the water sits for too long in storage or distribution. Similarly, while UV irradiation is effective in disinfecting water, it requires careful placement and does not leave any residual disinfectant in the water. Boiling