Question

In oxidation ponds sewage is mainly treated by

Answer 1

sunlight bacteria and algae

Answer 2

Oxidation pond is one of the biological systems which are used for the treatment of wastewater. It is considered as the secondary treatment method by which natural purification and stabilization of wastewaters like domestic sewage, trade waste and industrial effluents is accelerated. The biological treatment process in oxidation pond mainly involves an interaction between bacteria, algae and other organisms. It efficiently removes bacteria, biodegradable organics, phosphorous and nitrogen present in the wastewater which is going to be discharged to the receiving streams. In this method, 98% to 99% of BOD reduction in wastewater is often possible.