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The sedimentation tank is a critical component of the AguaClara design. Since AguaClara does not yet utilize filtration, the sedimentation tank is the location where virtually all of the suspended material removal occurs. Moreover, the important goal of minimizing construction costs means the tank should be as small as possible. Because of its relatively small surface area and the lack of a redundant or back-up removal mechanism, optimization of the sediment tank is a critical design goal.
The specific design challenge for the Inlet Manifold Research Team is to design an optimal inlet manifold for the sedimentation tank. Past AquaClara designs have evolved to inlet systems that currently feature PVC pipes with multiple holes (exit ports) creating vertical (downward) flow along the bottom of the pipe. The intent of the design is to create a smooth, quiescent influent condition that creates slow, upward flow through the sediment tank, ideally with the flocculated inflow initially traversing through a settled floc "blanket" that aids in removal. Some performance issues of past plants (lack of settling floc in one area of the tank, for example) have suggested that there may be non-uniform flow conditions in the sedimentation tank, leading to non-optimal performance.
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