Converting municipal solid waste to usable energy is an emergent and growing method for modern waste management. Through microbial facilitation of methanogenesis, methane gas can be extracted from landfill bioreactors to yield a significant amount of usable energy. The hypothesis was that a sufficient addition of sodium acetate to a controlled bioreactor environment would promote larger growth of methanogenic microbes and subsequently promote a greater amount of methane relative to a control (Madigan et al, 2003). In order to simulate an anaerobic bioreactor environment, the method for the study took place in modular sections to cover the design, construction and operation of laboratory scale bioreactors. Upon completion of bioreactor engineering, the biological and chemical components were scrutinized to match ideal conditions of a landfill. Methanosarcina was the chosen genus of the methanogen family to seed the bioreactors, and a total elemental analysis of the waste source was analyzed to approximate methane yield. Over 557 hours, each bioreactor produced approximately 1.3 liters of biogas with less than 1% containing methane. Given analysis through gas chromatography, the bioreactors may have had stunted methane production do to presence of argon gas in the headspace and/or low C/N ratio of the waste. The presence of argon should have been replaced with nitrogen, and the waste source should have contained more carbon per nitrogen. The generation-3 design of constructed bioreactors was successful in containing all gasses, liquids, and solids internally, however did not produce enough methane biogas to accept or reject the hypothesis.
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