What factor is used to gauge the effectiveness of disinfection in wastewater treatment?

Residual chlorine is a critical factor used to gauge the effectiveness of disinfection in wastewater treatment. It indicates the amount of chlorine that remains in the water after the disinfection process has taken place. Adequate levels of residual chlorine ensure that pathogens and harmful microorganisms have been sufficiently eliminated from the water, providing assurance that treatment objectives for public health protection are met.

In the context of disinfection, measuring the residual chlorine level allows analysts to confirm that enough chlorine was applied to achieve effective inactivation of bacteria and viruses. If the residual chlorine is too low, it may suggest inadequate disinfection, which could lead to the survival of harmful pathogens in the treated effluent.

While temperature, pH, and solids concentration can influence the disinfection process, they do not directly measure the effectiveness of disinfection in the same straightforward manner as residual chlorine. For example, higher temperatures may enhance disinfection but do not provide a direct indication of effectiveness. Similarly, while pH can affect chlorine's potency, it isn't an explicit measure of disinfection success. Solids concentration can interfere with disinfection processes but does not quantify how effective the disinfection was once the process is complete.