Sewage Treatment Plant
What is Sewage Treatment
A Sewage Water Treatment is a procedure of removing contaminated substances from waste water. This may include physical, chemical and biological processes to remove the contaminants to make water reusable for all purposes.
How Sewage Water Plants Work
1. Screening and Pumping- Here the waste water passes through equipment which are placed for screening. This is where objects such as plastics, wood, rags etc are removed. After this process the is pumped to another process.
2. Grit Removal- In this process, objects like sand and gravel are separated from the water.
3. Primary Settling- In this the material which were left in water after phase two of grit removal gets separated from water. these materials are taken out by circular tanks known as “Clarifiers”. The material which is left in water during this phase is known as “Primary Sludge” is pushed at the bottom of the tank while the water is pumped out from the top of of the tank.
4. Aeration/Activated Sludge- This is where the waste water gets most of the treatments. With the help of biological degradation, the microorganisms consumes all the pollutants and transform them into cell-tissues. This process is similar to the process of lakes and rivers where water gets purified naturally but it takes lots of time.
5. Secondary Settling- Large circular tanks known as “secondary clarifiers” let the wastewater to separate from the Aeration tanks at this point. The activated sludge continuously pumps from the bottom and returns to the Aeration tanks.
6. Filtration- As name suggest, this is the stage where the water is polished in step by step process of filtration. The materials that get stuck in the filters are sent back to plant head.
7. Disinfection- To make sure that water is free from all harmful germs and bacteria after filtration, the “Ultraviolet disinfection” is used which kills the remaining bacteria that can cause problem to health.
8. Oxygen Uptake- This is where the water is brought for further Aeration (if necessary) to revive the dissolved oxygen.