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I was a member of the spring 2013 Low Flow Stacked Rapid Sand Filtration research team. As a member of this team, I helped make improvements to the fabrication of the LFSRSF based on problems that were encountered when the unit was brought to Honduras in winter of 2013. One change that was made to the filter was to redesign the manifolds so that they would be more durable during operation, which was done because some of the manifolds broke in Honduras. This was done by changing to a system that uses one-half inch slotted PVC pipe connected by cross and tee sections. Another task was to design a sand drain, through which the sand can be removed when the filter bed is fluidized. The appropriate height, size, and orientation of this drain were determined to most efficiently drain the sand from the system.
The major task of the LFSRSF team in spring 2013 was to prepare for and present at the 2013 EPA Sustainable Design Expo. For this expo, our team designed and built (with significant contributions from Paul Charles) a small-scale demo filter to be brought to D.C. and continuously operated at the expo. The most difficult part of designing this demo filter was determining the flow rate and pipe diameters that would allow for appropriate fluidization of the filter bed during backwash. In D.C., the filter was continuously operated, visibly improving the turbidity of the filtered water, and it was also successfully backwashed several times.
Spring 2012 Contributions
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