Question 9021 of 234 · California Wastewater Operator Exam
A sludge pump runs 15 minutes each hour at 40 gpm. The sludge is 5 percent solids. How many pounds of solids are pumped per day? (Assume 8.34 lbs/gal)
Exactly one answer is correct.
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Correct answer to question 9021
- C: 6,005 lbs/day
Explanation
Gallons per day = 40 gpm x 15 min x 24 hr = 14,400 gal. Pounds of solids = 14,400 x 8.34 x 0.05 = 6,005 lbs/day. Forgetting the 5 percent gives the weight of all the sludge.
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