Which component of the conventional activated sludge process is responsible for disinfection?

The component responsible for disinfection in the conventional activated sludge process is the disinfection stage itself. This crucial step typically follows the secondary settling tank, where the treated wastewater is subjected to disinfection before being discharged or reused.

Disinfection is essential in wastewater treatment because pathogens and harmful microorganisms can remain present even after biological treatment. The disinfection process can utilize methods such as chlorination, ultraviolet (UV) light, or ozonation to effectively reduce or eliminate infectious agents, ensuring that the effluent is safe for the environment and public health.

The aeration tank is primarily involved in promoting the growth of microorganisms that break down organic matter. The secondary settling tank serves to separate the biomass from the treated water but does not provide disinfection. The primary settling tank, which precedes the aeration tank, mainly removes solids and allows for grease and grit removal. Therefore, the disinfection stage is distinct and specifically designed to address the safety and treatment of effluent by targeting microorganisms.