NCERT Solutions for Class 7th Science
Chapter 18. Wastewater Story
- Cleaning of water is a process of removing pollutants before it enters a water body or is reused.This treatment is commonly known as “Sewage Treatment”.
- Sewage is a liquid waste.Most of it is water, which has dissolved
and suspended impurities.These impurities are called contaminants.
- Full Form of (WWTP) is WASTEWATER TREATMENT PLANT.
- Wastewater is generated in homes, industries, agricultural fields and in other human activities. This is called sewage.
- A skimmer removes the floatable solids like oil and grease. Water so cleared is called clarified water.