The effectiveness of disinfection is primarily determined by what factor?

The effectiveness of disinfection in wastewater treatment is primarily determined by the coliform concentration in the effluent. Coliform bacteria are indicators of the presence of pathogenic microorganisms in the water. High concentrations of coliform can signify inadequate treatment and an increased risk of harmful pathogens being present.

When assessing the efficiency of disinfection methods, monitoring the coliform levels is essential because it directly relates to the water quality and safety for discharge or reuse. Disinfection processes such as chlorination, UV treatment, or ozonation are expected to significantly reduce coliform levels. If the coliform concentration remains high post-disinfection, it indicates that the process may not be working effectively, which could pose health risks.

In contrast, while factors like total suspended solids, temperature and pH, and flow rate through the disinfection unit are important aspects of the treatment process, they do not directly measure disinfection effectiveness in the same way coliform concentration does. Suspended solids can interfere with disinfection efficiency by shielding bacteria from the disinfecting agent, but they are not an indicator of the system's disinfection capacity. Temperature and pH can influence the disinfection process, but they are secondary factors compared to the coliform levels that measure the disinfection outcome. Flow rate