Process in Anaerobic Sludge Digester

Q. During sewage treatment, biogas is produced in

1. secondary treatment plant
2. biological treatment plant
3. anaerobic sludge digesters
4. primary treatment plant

Q. What would happen if oxygen availability to activated sludge flocs is reduced?

1. The centre of flocs will become anoxic which would cause death of microbes and eventually breakage of flocs
2. The rate of organic matter degradation will increase
3. Flocs will increase in size as anaerobic bacteria would grow around flocs
4. Protozoa would grow in large numbers

Q. During the secondary treatment of sewage, the primary effluent is constantly agitated and air is pumped into it. Select the option which gives the correct reason for this.

1. For preventing the growth of aerobic microbes
2. For the vigorous growth of anaerobic microbes
3. For the vigorous growth of aerobic microbes
4. For the vigorous growth of both aerobic and anaerobic microbes

Q. Statement 1: The technology of biogas production was developed in India by the joint efforts of Indian Agricultural Research Institute (IARI) and Khadi and Village Industries Committee (KVIC)

Statement 2: Ganga Action Plan and Yamuna Action Plan was initiated by the Ministry of Environment and Forests, Government of India.

1. Both statements are correct
2. Statement 1 is correct while statement 2 is incorrect
3. Statement 2 is correct while statement 1 is incorrect
4. Both the statements are incorrect

Q. Waste water treatment generates a large quantity of activated sludge, it can be treated by:

1. Anaerobic digesters
2. Flocs
3. Chemicals
4. None of these

Q. Sewage treatment promises the production of biogas that could be used as a source of energy for various purpose. Indian villages have adopted the Biogas generation at a small scale using Cow dung as the raw material for production of Biogas.
How does sewage treatment help in biogas production?

1. None of the above.
2. The flocs acting on the effluent produces biogas.
3. The flocs are active microbes. Once the nutrients are gone, they die and decay, which produces biogas.
4. The secondary sludge left behind after the flocs act on nutrients, produces biogas when acted upon by anaerobic bacteria.

Q. (a) Describe the process in which BOD is reduced during sewage treatment.
(b) What is activated sludge?
[3 marks]

Q. The technology of biogas production was developed in India mainly due to the efforts of _____ and ______.

1. A - IARI, B - STP
2. A - KVIC, B - IPM
3. A - IARI, B - KVIC
4. A - STP, B - IPM

Q.

Chlorination (treatment with chlorine) is done in ___________.

1. Primary Treatment

2. Secondary treatment

3. Tertiary Treatment

4. All of these

Q. Waste water treatment generates a large quantity of activated sludge, it can be treated by:

1. Anaerobic digesters
2. Chemicals
3. None of these
4. Flocs

Q. What are the different processes that happen in following numbered tanks in a sewage treatment plant.

1. 1.Sedimentation and filtration 2.Aeration 3.Settling 4.Anaerobic digester
2. 1.Sedimentation and Filtration 2.Aeration 3.Settling 4.Anaerobic digester
3. 1.Anaerobic digester 2.Sedimentation and Filtration 3.Settling 4.Aeration
4. 1.Settling 2.Aeration 3.Anaerobic digester 4.Sedimentation and filtration

Q. Waste water treatment generates a large quantity of activated sludge, it can be treated by:

1. Anaerobic digesters
2. Chemicals
3. None of these
4. Flocs

Q. The domestic sewage in large cities

1. has high BOD as it contains both aerobic and anaerobic bacteria
2. is processed by aerobic and then anaerobic bacteria in the secondary treatment in Sewage Treatment Plants (STPs)
3. when treated in STPs does not really require the aeration step as the sewage contains adequate oxygen
4. has very high amounts of suspended solids and dissolved salts

Q. What is represented by letter A, B and C?

1. A- oxygen, B- organic matter, C- BOD
2. A- BOD, B- organic matter, C- oxygen
3. A- organic matter, B- BOD, C- oxygen
4. A- dissolved oxygen, B- BOD, C- organic matter

Q. Waste water treatment generates a large quantity of activated sludge, it can be treated by:

1. Anaerobic digesters
2. Flocs
3. Chemicals
4. None of these

Q. BOD is related with

1. Organic matter
2. Microbes
3. Both A and B
4. None of the above

Q. What are the different processes that happen in following numbered tanks in a sewage treatment plant.

1. 1.Sedimentation and filtration 2.Aeration 3.Settling 4.Anaerobic digester
2. 1.Anaerobic digester 2.Sedimentation and Filtration 3.Settling 4.Aeration
3. 1.Sedimentation and Filtration 2.Aeration 3.Settling 4.Anaerobic digester
4. 1.Settling 2.Aeration 3.Anaerobic digester 4.Sedimentation and filtration

Q. What is being depicted in this graph?

1. Mineral rich water
2. BOD
3. Green house gases
4. Oligotrophic pond