8. What is the key difference between primary and secondary sewage treatment?
The differences between the primary and secondary treatment of sewage are as follows:
Primary sewage treatment | Secondary sewage treatment |
Primary sewage treatment is a mechanical process that removes solid waste materials | Secondary sewage treatment is a biological process in which waste materials are enzymatically treated by bacteria and other microbes |
It is a less expensive and simple process | It is an expensive and complicated process |