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What is The biological oxygen demand (BOD) indicates and explain in detail?
Biological Oxygen Demand (BOD): Is defined as ‘amount of oxygen absorbed by a sample of sewage’ during a specified period (Generally 5 days), at a specified temperature (generally 20° C) for aerobic destruction or use of organic matter by living organisms.
Strong Sewage has BOD > 300 g/litre and Weak Sewage has BOD < 100 g/litre.