Plain sedimentation basins operate at an overflow rate averaging roughly__________________?
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Answer: A. 500 to 750 litres/hour/ m2
Explanation
Plain sedimentation basins operate at conservative surface overflow rates typically ranging from five hundred to units. Surface overflow rates between five hundred and seven hundred fifty liters per hour per square meter ensure settling. Operating within this specific range allows discrete suspended particles to settle before leaving the basin. Surface overflow rate is defined as the total water flow divided by the horizontal surface area of tank. Plain sedimentation occurs without adding chemical coagulants relying solely on gravity for particle removal. Basin depth does not affect particle settling velocity which is governed by surface area and overflow rates.
One thousand to twelve hundred fifty liters per hour per square meter is typical for rapid settling tanks. Twelve hundred fifty to fifteen hundred liters per hour represents high rate settling with chemical aids. Fifteen hundred to two thousand liters exceeds conservative plain sedimentation limits causing solids carryover.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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