Class 12th Biology 2016 Set3 Delhi Board Paper Solution
Question 7
Distinguish between the roles of flocks and anaerobic sludge digesters in sewage treatments.
Answer
| Flocks | Anaerobic sludge digesters |
| These are masses of bacteria associated with fungal filaments to form a mesh | These consist beacteria and fungi is digensted by anaerobic bacteria. |
| These helps to reduce the BOD of primary effluent | These work on the secondary effluent |
| They breakdown organic matter aerobically | They breakdown organic matter anaerobically |
| These do not prduce biogas. | These helps in production of biogas consisting of methane,hydrogne sulphide (H2S) and carbon dioxide (CO2) |
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