Question

Acceptable lower limit of bacteria removal through activated sludge process is ...........

• A. 60%
• B. 70%
• C. 80%
• D. 90%

Hint:

The activated sludge process is widely used in secondary wastewater treatment due to its effective reduction of organic content and pathogens, including bacteria.

Answer 1

The Correct Option is D

The activated sludge process is a biological wastewater treatment method known for its high efficiency in removing organic matter and pathogens. Among its many benefits is its high bacterial removal efficiency. Typically, the acceptable lower limit for bacterial removal via this process is around 90%, though in well-operated systems it can be even higher. This value reflects the minimum standard to ensure the treated effluent is safe for discharge or further treatment. Hence, the correct answer is (4) 90%.