Correct Answer - Option 3 : Sedimentation
Explanation:
The sequence of the process in the water treatment plant:
Coagulation & Flocculation → Sedimentation → Filtration → Chlorination
Coagulation:
Coagulation is the process in which certain chemical termed coagulants are added to neutralize the negative protective charge present over the suspended particles so as to increase the opportunity of the contact between the neutralized particles and a sticker precipitate resulting in the formation of a bigger size particle which results in the formation of a bigger size particle which can get easily settled in the following sedimentation process.
Flocculation:
- It is a process in which neutralize particles are gotten intimate contact with each other and with a sticky precipitate resulting in the formation of bigger size particles that can get easily settle in the following sedimentation tank.
- In order to increase the opportunity to combine between the particles, slow mixing is also induced in this process.
Sedimentation:
- It is the process of removal of suspended particles from the water.
- The entire theory of sedimentation is based upon a single parameter termed Specific gravity.
- In this process, particles are allowed to settle in the tank due to their own weight and then get removed.
Filtration:
- Filtration is most often a policing step to remove flocks or smaller un-sedimented particles.
- Filtration also removes dissolved organic matter, dissolved minerals, and microorganisms.
Chlorination:
Chlorination is the most popular method of disinfection in which disinfection is done with the help of chlorine.
