Civil - Environmental Engineering - Sewer Design
Important Question And Answer: Sewer Design
1. What are the Demerits of chemical precipitation?
· High cost of chemicals
· Large quantity of sludge which offers difficulty of its removal
· Skilled attendance
· Putrescible efficient
2. What do you mean by chemical precipitation?
When certain chemicals are added to, sewage they produce a precipitate known as flow which in insoluble or slightly soluble in water. The flow attracts small particles to form large size and thus size goes on increasing during the process of settlement.
3. What is do you mean by transitional setting zone?
Grit particles however, generally lie between 0.1mm and 1 mm, and hence undergo settling which lies in between streamline settling and turbulent settling. This settling zone is called the transitional settling zone
4.What are the users of Baffle?
· Baffler are required to prevent the movement of organic matter and its escape along with the efficient
· Distribute the sewage uniformly through the cross section of the tank.
· It is used to avoid short circuiting
5.What are the classifications of biological process?
· Aerobic processes
· Anaerobic processes
· Aerobic –anaerobic processes
· Activated sludge processes
· Trickling filters
· Aerobic stabilization pond
· Aerated lagoon
7.List out the anaerobic process?
· Anaerobic sludge digestion,
· Anaerobic contact processes
· Anaerobic filters
· Anaerobic lagoons or ponds
8.What are the sources of waste water?
· Domestic waste water (i.e sewage)
· Agricultural return waste water
· Industrial waste water
9.What are the methods involved in the treatment of waste water?
Mainly classified into
· Conventional treatment methods
· Advanced waste waster treatment
Conventional treatment methods
· Preliminary processes
· Primary treatment
· Secondary treatment
Advanced waste water treatment
· Tertiary treatment
10.What are the functions involved in the chemical unit processes
· Chemical precipitation
· Gas transfer
The waste water treatment or sewage treatment is a broad term that applies to any process/operation or combination of processes and operations that can reduce the objectionable properties of water carried waste and render it less dangerous with the following.
· Removal of suspended and floatable material
· Treatment of biodegradable organics
Elimination of patheogenic organisms