Andrew Kim's Individual Contribution Page

Fall 2016 Goals

This semester we are planning on continuing our research on high strength wastewater for UASB applications in the Global South. We plan on making day-to-day operations smoother by addressing the problems encountered during the summer. This includes modifying wastewater influent lines and rethinking biogas collection systems. We will then increase the OLR to mimic "black water" feed into the reactors, and attempt to reduce the HRT. The parameters that lead to VFA accumulation will be measured and will be incorporated as upper bounds into models that predict energy production for small-scale communities in Honduras. Other experiments to be explored are tracer tests to determine the exact hydraulic residence time, as well as preparing for air stress tests to the methanogenic community. 

Summer 2016 Contributions

Under the Engineering Learning Initiatives grant, I operated the UASB reactors fabricated in Spring 2014. My tasks were to test for leaks and gas-tightness of each reactor, design an optimal system for wastewater stock delivery, and monitor biogas production. I have implemented a method for detecting biogas production by using pressure sensors to measure head displacement from biogas production, similar to the method adopted by the Fall 2015 team. I have adopted ferrule compression tubings as they are much more gas-tight and should be used instead of push-to-connect tubings. For reactors with push-to-connect tubings still in place, three-way luer lock valves were used to allow a septa for GC measurements. From the GC, it was found that biogas composition was approximately 60% methane. COD removal for the reactor was also found to be around 50%. The OLR for the summer was around 5 g COD/l-day, with an HRT of 4 hours. These parameters will be explored more in depth in future semesters.