Abstract

Biological treatment is the most widely used method for removal, as well as partial or complete stabilization of biologically degradable substances present in wastewaters. Most often, the degradable substances are organic in nature and may be present as suspended, colloidal, or dissolved matter. Most of the conventional biological wastewater treatment processes are based on naturally occurring biological phenomena, but are carried out at accelerated rates. In recent years, cultures have been developed for biological treatment of many hard‐to‐degrade organic wastes.