Question

Describe the steps involved in getting clarified water from wastewater.

Answer 1

Wastewater treatment consists of physical, chemical, and biological processes that remove physical, chemical, and biological contaminants from the wastewater. The following steps are involved in getting clean water through the treatment of wastewater:

1. Bar screens: Wastewater is filtered using bar screens, which remove big materials such as rags, sticks, cans, plastic bags, napkins, and so on.
2. Grit and sand removal: Water flows through a grit and sand removal tank, where sand, grit, pebbles, and other debris fall to the bottom and are removed.
3. Sedimentation tank: Water is then allowed to enter a tank where particles such as faeces (known as sludge) settle to the bottom and are scraped away. A skimmer removes floatable items such as oil and grease. Water that has been cleansed is referred to as clarified water. Sludge is collected in digesters and used to make biogas.
4. Aerator: The clarified water is next sent through an aerator tank, which pumps air into the water. It promotes the growth of aerobic bacteria that degrade organic substances, such as human and animal waste. After a few hours, the suspended microorganisms settle to the bottom of the tank as activated sludge. The water is then evacuated from the surface. The dried and activated sludge is utilized as manure.
5. Chlorination: The treated water has a low amount of organic material and suspended materials. It is dumped into the ocean, a river, or the earth. It may be treated using chemicals such as chlorine and ozone before being discharged into bodies of water.