Biological treatment of effluents: an overview

摘要

The objectives of biological treatment of waste water are to coagulate and remove the non settleable colloidal solids and to stabilize the organic matter. For domestic waste water, (that is sewage), the major objective is to reduce the organic content and in many cases, the nutrients such as nitrogen and phosphorous. For agricultural return wastewa-ter, the objective is to remove the nutrients, specifically nitrogen and phosphorous that is capable of stimulating the growth of aquatic plants. For industrial wastewater, the objective is to remove or reduce the concentration of organic and inorganic compounds.