Question

Explain the different steps involved during primary treatment phase of sewage.

Answer 1

The primary treatment phase of sewage involves the removal of coarse solid materials through filtration and sedimentation. The diluted sewage is passed through a series of filters of sequentially small pore sizes to remove large floating objects. Then the filtered sewage is passed into the grit chamber where the coarse solid materials settle by gravity. After this, the sewage is allowed to pass into a sedimentation tank where the suspended materials settle and form the primary sludge. The effluent is then taken for the secondary treatment.