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The elevation of the clear well is Clear Well sub team developed a simple design based on placing the clear well's elevation between that of the filter beds and the effluent source of the sedimentation tank. During normal operation, this elevation difference gravity drives the allows effluent from the sedimentation tank to flow through the filter and be subsequently distributeddistribute. Backwash requires approximately ten times the flow rate as normal operation. Backwash is accomplished by closing the valve leading to the distribution lines whereby water accumulates in the filter beds until the head difference between the clear well is sufficient and filtered water accumulates in the clear well.

We based our initial design on empirical granular filtration equations from existing works literature on granular filtration. Our experiments involved developing A bench-scale model of our system was built and tested to observe the discrepancy between the actual fluidization velocity and the calculated fluidization velocity required to achieve a target bed expansion. We noted an increasing difference between those two sets of values that prompted us to hypothesize that, if we were to base our design on these empirical equations, we need to implement a significant safety factor. Further experiments are needed before we can conclude whether or not our design is feasible.

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