LFSRSF, Summer 2014

Richa Gwalani, Guneet Sandhu, Tom Schultz, Savannah Wing

Abstract

People in many parts of the world are still devoid of basic human necessity like clean drinking water. Many drinking water treatment systems in the global south face limited economic viability because of the unreliable source of electricity and expensive operation costs. Stacked Rapid Sand Filters (SRSF) were invented by the AguaClara team to eliminate the need for pumps or control equipment, thus making it more robust and reliable than conventional rapid sand filters. The low-flow stacked rapid sand filter (LFSRSF) is an adaptation of the SRSF for flow rates < 3.0 L/s and is currently being deployed in India for flow rates of 0.8 L/s serving communities of about 500 people. The previous LFSRSF research teams have been working on fabricating the laboratory version (version 1) of the filter with continuous improvements to the design aimed at simplifying the operation and maintenance of the filters. This version of the full-scale filter in the lab fabricated by the previous team has 0.2mm slotted pipes throughout and top and bottom manifolds consisting of single slotted pipes. The initial version 1filter is nearing completion in two villages in India, Rohne and Gufu. Our work was to fabricate the next version full-scale filter, version 2, which was built upon the previous teams version 1filter. In the 2nd version of the full-scale filter, we tried to mitigate problems faced by the previous version, such as overflowing of the inlet tank and the inability to backwash at designed ow rates. We also wanted to move towards the ability to handle and filter turbid water. This 2nd version of the full-scale LFSRSF will be used as a prototype for mass production by the Tata Water Mission in India. A major part of optimizing the operation of the filters included accounting for head loss incurred in the system and incorporating these changes in the final design of the critical components of the filter.

Laminar Tube Flocculator - Summer 2014

Shreya Jain, Tanya Peifer, Nadia Shebaro, and Luke Zhu

Abstract:

Over the summer of 2014, the laminar tube flocculation team has worked to test AguaClara's new residual turbidity monitoring system, SWaT, as compared with prior teams that used FReTA. The group has also implemented PID control for the laminar tube flocculator to regulate the amount of clay added to the system. In order to achieve these goals, the laminar tubing system was simplified and reconfigured to eliminate the feedback loop with the turbidimeter. The team plans to continue optimizing the system and confirming the self regulating controls were working before starting experiments using varying dosages of coagulant.

Foam Filtration - Summer 2014

Abby Brown, Ethan Keller, Skyler Erickson, Ji Young Kim

Abstract:

The Summer 2014 Foam Filtration team will continue to improve the water treatment system, aiming to send a complete filter design to Honduras in July 2014. The goal of the summer is to verify the safety of the foam filter itself and to improve the design of the filtration system for better performance, easy fabrication and transportation. The foam filter will be additionally tested in Honduras.

Turbulent Tube Flocculation, Summer 2014

Shreya Jain, Tanya Peifer, Nadia Shebaro, Luke Zhu

Abstract

Over the summer of 2014, the turbulent tube flocculation team has worked to implement and test a SWaT system for analyzing residual turbidity from the flocculator. The group is also working to implement PID control for the turbulent tube occulator to regulate the amount of clay added to the system. The team made minor physical adjustments to the turbulent occulator through the shortening of tubes and the tube settler position. By the end of the summer research period, the team has established a working occulation system to facilitate experiments done by future teams.