AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Air Quality Implications of Biomethane Combustion in Microturbines, Industrial Engines, and Home Appliances
YIN LI, Jian Xue, Joshua Peppers, Christoph Moschet, Chris Alaimo, Peter Green, Norm Kado, Minji Kim, Christoph Vogel, Thomas Young, Michael Kleeman, University of California, Davis
Abstract Number: 594 Working Group: Combustion
Abstract Biomethane has the potential to act as a major renewable energy resource in California and other locations where the use of traditional fossil fuels is not consistent with GHG mitigation goals. Biomethane is produced from the anaerobic digestion of waste streams containing organic material over a period of several weeks. The unique production pathway combined with the rapid timescales lead to trace compounds in biomethane that are not present in traditional natural gas. Product biogas typically contains 50% methane that is then purified to +95% methane prior to use. The health effects of the residual trace compounds must be fully analyzed before widespread adoption of biomethane as a fuel for use in industry, transportation, and residential applications.
In this study the chemical composition and possible health impacts of biomethane were studied across multiple end-use scenarios. As a first step, the composition of raw biogas was measured to characterize fugitive emissions from production facilities. As a second step, the exhaust from micro-turbines and industrial engines burning raw biogas was drawn into a 5.5 m3 Teflon reaction chamber and aged for 3 hrs to study the photochemical reaction products and regional exposure. Gas and PM samples were collected on a wide variety of sampling media to support comprehensive analysis. As a third step, upgraded biomethane was produced from the biogas and was then used in home appliances. The exhaust from these appliances was once again drawn into a 5.5 m3 Teflon reaction chamber and aged to study residential exposure. The chemical, biological, and toxicity results from all samples will be presented, and the air quality implications of widespread biomethane adoption will be discussed.