The modelling of dispersion of VOC emissions from sanitary landfills

Nowadays, the amounts of solid wastes increasing with increasing population and urbanization have brought about the necessity of disposing them in a sanitary manner. As known to all, sanitary landfilling is certainly the most widely used method for solid waste disposal among other methods like incineration and composting. The biodegradation of solid wastes, which are deposited in this manner, continues in the landfill site after the disposal. As a result of biological decomposition, leachate and gas emissions form. Among the gas emissions, some odorous compounds are released to the atmosphere and these odorous compounds cause odor problem in neighboring areas. In this study, the atmospheric dispersion of odorous compounds released to the atmosphere from Odayeri Sanitary Landfill Site was estimated via a model approach; a concentration modeling was done in Gokturk which is the nearest residential area. Some of the odorous compounds (22 VOC and hydrogen sulfide) were studied in the model. The odorous compounds that are subject to this study were chosen among those whose odor threshold concentrations are known in the literature. In the study, long-term modeling (LTM) was studied. ISCLT3 was used for LTM. The results of the model have shown that two VOC species (ethyl mercaptan and methyl mercaptan) may lead to odor problem near or within the landfill site but not in Gokturk. LTM results lead to the possibility that these two species may cause odor problems in Gokturk under specific meteorological conditions; therefore, a short-term model (STM) was also done. MCGP 2.0 was used in STM and the results showed that, under specific meteorological conditions, one of these species (ethyl mercaptan) causes odor problem in Gokturk. As a matter of fact, the inhabitants of Gokturk complain of odor from time to time, which supports the model results.