Under what conditions is aerobic biological activity at its peak_______________?
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Answer: A. In freshly produced sewage
Explanation
Freshly produced sewage contains high dissolved oxygen levels and abundant organic food nutrients. Aerobic bacteria flourish rapidly when oxygen is plentiful before septic conditions develop. As sewage ages oxygen gets depleted halting peak aerobic biological activity entirely. Fresh wastewater enters sewer networks directly from plumbing fixtures with dissolved oxygen present. Biological activity in wastewater depends directly on available oxygen and nutrient concentrations. Anaerobic bacteria take over wastewater decomposition once dissolved oxygen is completely exhausted.
Sanitation engineers design collection systems to minimize sewage detention times and prevent septicity. Understanding biological activity stages helps in operating municipal wastewater treatment facilities. Fresh sewage treatment requires less chemical intervention than septic stale wastewater streams. Sewer pipes often develop anaerobic conditions due to restricted oxygen transfer rates. Sewage treatment plants receive stale wastewater requiring specialized aeration to restore aerobic activity. Option A is correct so none of these is an incorrect statement.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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