in Microbes in Human Welfare by

1 Answer

0 votes
Difference between primary and secondary sewage treatment


Primary sewage treatment

Secondary sewage treatment


It is a physical method of treatment

It is a biological method of treatment


It involves in removal of large particles and floating materials such as leaves, papers, rags, solids such as sand, grit and oily substances

It involves the removal of fine suspended and dissolved organic matter.


It makes the used of sedimentation and filtration process

It makes the use of aerobic or anaerobic biological units


It is relatively simple and less time consuming process

It is relatively complex and takes a long time for its completion