Engineering Board Exam Reviewer · Environmental Engineering · medium
A water treatment plant treats 20,000 m3/day. The chlorine demand is 2.5 mg/L and the required residual is 0.5 mg/L. How much chlorine is needed per day?
- 60 kg/day
- 50 kg/day
- 40 kg/day
- 60000 kg/day
Answer
A. 60 kg/day
Solution
Dose = demand + residual = 3.0 mg/L (= g/m3). Mass = 20,000 m3/d × 3.0 g/m3 = 60,000 g/d = 60 kg/day.
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