Production of non-methane organic compounds during refuse decomposition in a laboratory-scale landfill

The presence of non-methane organic compounds (NMOCs) in landfill gas is well documented. However, there is little understanding of the degree to which the production of NMOCs should be attributed to the volatilization of household hazardous waste as opposed to intermediates of the anaerobic decomposition of the major cellulosic components of municipal solid waste. The objectives of this study were: (1) to compare the NMOC yields for decomposed refuse, fresh residential refuse, and a synthetic refuse; and (2) to evaluate the source of NMOCs emitted during refuse decomposition. Replicate 2-l reactors were filled with shredded residential refuse expected to contain household hazardous waste, synthetic refuse containing no hazardous constituents, and control reactors with decomposed refuse only. Anaerobic decomposition of each refuse was initiated with a seed of decomposed refuse, and the reported methane and NMOC yields were corrected for that attributable to the seed. The NMOC yields from the seed, synthetic refuse, and residential refuse were comparable (0.62 to 1.01×10-4 g NMOC (dry g)-1, suggesting that the volatilization of hazardous organic compounds is not the sole source of NMOCs in landfill gas and that anaerobic biodegradation intermediates also contribute to NMOCs.