Gaseous emissions in municipal wastes composting: effect of the bulking agent.

In this study, the emissions of volatile organic compounds (VOC), CH4, N2O and NH3 during composting non-source selected MSW, source selected organic fraction of municipal solid wastes (OFMSW) with wood chips as bulking agent (OF_wood) and source selected OFMSW with polyethylene (PE) tube as bulking agent (OF_tube) and the effect of bulking agent on these emissions have been systematically studied. Emission factors are provided (in kg compound Mg(-1) dry matter): OF_tube (CH4: 0.0185±0.004; N2O: 0.0211±0.005; NH3: 0.612±0.269; VOC: 0.688±0.082) and MSW (CH4: 0.0549±0.0171; N2O: 0.032±0.015; NH3: 1.00±0.20; VOC: 1.05±0.18) present lower values than OF_wood (CH4: 1.27±0.09; N2O: 0.021±0.006; NH3: 4.34±2.79; VOC: 0.989±0.249). A detailed composition of VOC is also presented. Terpenes were the main emitted VOC family in all the wastes studied. Higher emissions of alpha and beta pinene were found during OF_wood composting processes.