Page History

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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, to develop an apparatus, run experiments, and collect data. These experiments seek to identify the relevant failure mode controlling the spacing of lamellar sedimentation devices.

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 backwashthe first laboratory version of the filter to demonstrate the filtration and backwash cycles and show that the SRSF is a viable concept worthy of further research.

Fall 2010

During Fall 2010, I have been leading led the Stacked Filtration team as we continue continued 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 rounded out a proof-of-concept for the SRSF by observing backwash cycles and collecting additional performance data. We have shown that a stacked filter can do everything a conventional filter can do, in a way that makes it practical for use around the world. We also began exploring 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.

January 2011

At the end of the Fall 2010 semester, the SRSF team built a transportable demo unit in a 3" clear pipe. During winter break, I traveled to Honduras with the AguaClara group, and worked with Jeff Will and Anderson Cordero to demonstrate the filter at Tamara, Agalteca, and Marcala. Our results suggest that the system is viable in the field, and we learned a number of important lessons about the practical challenges this technology will face.

Spring 2011

In Spring 2011, I once again led the SRSF team along with Anderson Cordero. Now that we had proven the basic concept of stacked filtration, there were a number of practical questions that remain be addressed as the system moved towards full-scale design and implementation. Our experiments this semester focused on design and operational issues for the SRSF in advance of its first full-scale trial.

I also continued to work with the plate settler spacing group, setting up and running experiments and helping with data analysis and organization.

Summer 2011

In the summer of 2011, Anderson and I had the exciting opportunity to work in Honduras bringing the SRSF from the lab to the field. We worked at the Tamara plant for two months to finish the detail designs of the first ever full-scale SRSF and begin the process of construction. The full-scale SRSF came online in October 2011 and began producing water meeting US EPA standards!!

In August 2011, I presented on behalf of AguaClara at the World Water Week conference in Stockholm, Sweden. Our poster was titled "Quality Drinking Water from Economically Sustainable Municipal Infrastructure: Examples from AguaClara in Honduras."

Fall 2011

In Fall 2011, I served alongside Karen as one of the AguaClara teaching assistants. I was involved in a variety of research projects, advising the Demo Plant, Foam Filtration, Plate Settler Capture Velocity, and Stacked Rapid Sand Filtration teams. In addition to this bench-scale and pilot-scale technical research, I helped with additional research on the socio-economic aspects of AguaClara with Karim Beers and Matt Fisher-Post.

I made a brief trip to Honduras in October 2011 during Fall Break, where I worked with Jeff Will and Tamara plant operator Antonio Cerrato to turn on the full-scale SRSF for the first time.

January 2012

I had the opportunity to travel on the student trip once again in January 2012. It was a real pleasure to visit some of the people that Anderson and I lived and worked with last summer, and to see the inauguration ceremony for the full-scale SRSF. I don't think many water plants are the subject of such awesome celebrations!!

Spring 2012

In Spring 2012, I was co-TA for the AguaClara class with Karen once again. I advised the Demo Plant, Foam Filtration, and Ram Pump teams, along with Stacked Rapid Sand Filtration research at the bench, pilot, and field scale. I also conducted an independent study with Dr. Marcela Gonzalez Rivas in CRP, where we developed a conceptual framework to evaluate the overall sustainability of AguaClara projects and studied the links between engineering and effective governance.

Summer 2012

I am currently working with the summer research program, advising the Foam Filtration, Stacked Rapid Sand Filtration, and Floc-Sed Optimization teams. I am also finishing some technical manuscripts related to work I have done here over the past two years.