Exemplar Problems

Question:

What is the key difference between primary and secondary sewage treatment?

Answer:

• The key difference between primary and secondary sewage treatment is in their processes and objectives:
  • Primary sewage treatment is a physical process that involves the removal of large solid particles and the separation of liquids and solids. It aims to reduce the suspended solids content in sewage.
  • Secondary sewage treatment is a biological process that focuses on the removal of organic matter and dissolved pollutants from sewage. It uses microorganisms to break down organic substances and purify the water further.