Question 9026 of 234 · California Wastewater Operator Exam
An activated sludge system has 37,530 lbs of solids in the aeration tank and 6,000 lbs in the clarifier. Solids leaving per day are 3,336 lbs in the waste sludge and 167 lbs in the effluent. What is the MCRT?
Exactly one answer is correct.
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Correct answer to question 9026
- D: 12.4 days
Explanation
MCRT = solids in the system / solids leaving per day = (37,530 + 6,000) / (3,336 + 167) = 43,530 / 3,503 = 12.4 days. Leaving out the clarifier solids or the effluent solids gives a different result.
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