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The application of Appropriate Technology

Horizontal Flow Roughing Filter

Manual detailing how to estimate and design horizontal flow roughing filters.

Among pre-treatment methods used before slow sandfilters (SSF), horizontal-flow roughing filters( HRF) have been found to be the most effective and appropriate for application in developing countries. This is because they are simple, require no mechanical parts, have low capital cost, can be operated for a long time due to their high solids retention capacity, and with a wide variety of raw surface water characteristic. Most research on HRFs has concentrated on turbidity (solids) removal whereas the way to estimate and design the run duration time before filter cleaning is necessary has received little attention. In this research, a large gravel (size l0-20 mm) filter media were placed as a single package, uncovered and outlet at the top.

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