Mickey's Individual Contribution Page

Summer 2010

During Summer 2010, I worked on the ongoing Plate Settler Spacing project. We spent the first portion of the summer working on the bench-scale treatment train apparatus to achieve consistent and replicable performance. We then collected some interesting data on the performance of tube settlers of various diameters. Floc roll-up failure modes were observed for small tubes, where higher velocity gradient led to poorer performance even at the same predicted capture velocity. It appears that plate settlers could be more tightly spaced wand will still perform well, but the velocity gradient must be considered.

I also joined the Stacked Rapid Sand Filtration team, which during the summer of 2010 made the transition from theory to the bench-scale. We constructed a 4" diameter four-layer stacked filter, and a system to dose it with clay and alum to resemble sedimentation tank effluent. This research provided an important proof-of-concept for the stacked filtration technology. The filter showed good turbidity removal performance meeting EPA water quality standards, and backwashing effectively cleaned the filter bed even when 5 NTU water was used in backwash.

Fall 2010

During Fall 2010 I have been leading the Stacked Filtration team as we continue to develop the technology. We have built a six-layer filter that can be run at the same flow rate for filtration and backwash, inside a clear 4" column so that bed expansion and settling can be observed. We are further investigating the performance of the filter so we can be confident that it will be an effective treatment process at AguaClara plants. We are also studying flow distribution among layers of the filter using dye tracer tests, and investigating the backwashing process by measuring bed expansion and developing methods to properly settle the bed.

I have continued to contribute some experimental assistance to the Plate Settler Spacing team, based on my experience from Summer 2010.