Research On The Characteristics Of Odorous Gasses In The Typical Municipal Solid Waste Landfill Site

Landfill is the major disposal method in China recently and in the long-term future.Municipal solid waste (MSW) landfills are one of the major sources of offensive odourspotentially creating result in annoyance in the surrounding population in the world wide.In recent years, the odour pollution incidents had always occurred in many typicalMSW landfills all around China, where the residents lodged complaints about theintense odour from the landfill, which drew a significant attention from the government.In this study, ambient air monitoring was conducted in the Asuwei landfill site, Beijing.The main odour composition of the gas samples collected in spring was sampledusing “lung method” and determined using gas chromatography-mass spectrometry(GC-MS), which detected57odorous gases in total. The sampling positions include thedumping area, the landfill gas pipes and the static chamber, and there were44,39and36odorous gases which had been measured and quantified.The environmental sampling point of the dumping area was found to be the mainodour sources at Asuwei landfill site. The measured odorous gases included inorganiccompounds (e.g., ammonia and hydrogen sulfide), halogenated compounds (e.g.,chlorobenzene), aromatics (e.g., benzene, toluene), ketones, esters, hydrocarbon (e.g.,hexane and octane), other sulfur and nitrogen compounds (e.g., dimethyl sulfide, methylmercaptan).The difference between odour components in China and in the developed countrieswas mainly due to the different components of waste. The difference among thecomponents of landfill gas from different depth was due to different stages of waste’sdegradation. The ratio of BTEX (Benzene, Toluene, Ethylbenzene, Xylenes) in landfillsource and city source had significant differences; the B/T ratio in China was higherthan USA and other developed countries.In addition, variations of primary odorous gaseous (H2S and NH3) concentrationsat different time in the landfill site during sampling day were also investigated by usingonline data. Results showed that H2S was the notable odour component contributing to5.63–30.10%of total concentrations. According to the correlations analysis by SPSS,the temporal shift of H2S concentration was observed and was significantly affected byenvironmental factors including temperature and relative humidity.Moreover, the emission fluxes of trichlorofluoromethane and other7odorous gaseswere determined by the static chamber method. Specially, the annual emission oftrichlorofluoromethane was comparable with the estimation figure by the software ofUSEPA’s LandGEM.