Emission of volatile organic compounds from solid waste disposal sites and importance of heat management
ABSTRACT; Taro Urase, Hiroyuki Okumura, Samerjai Panyosaranya, and Akihiro Inamura. Waste Management Research, 26, 534-538, 2008.
Emission of volatile organic compounds (VOCs) from a solid waste disposal site for non hazardous wastes was quantified. The type of VOCs found at landfill gas in a municipal solid waste disposal site were benzene, toluene, xylenes, ethyl benzenes, trimethyl benzenes, while the concentrations of chlorinated compounds were very low. The highest benzene concentration found in the landfill gas samples was more than 20 mg/m3, and benzene to toluene ratio (B/T) was between 0.2 and 8. The higher emissions of VOCs to landfill gas and to leachates were observed at high temperature area of the target site. The release of VOCs in the solid waste disposal site was explained partly and quantitatively by the exposure of poly stylene plastic to heat generated by biodegradation of organic solid waste.
Keywords; Volatile organic compounds, Solid waste disposal, Landfill gas
Micropollutants in leachate from Nonthaburi solid waste disposal site in Thailand
ABSTRACT; Taro URASE, Jiro TAKEMURA, Hiroyuki OKUMURA, Samerjai PANYOSARANYA, Chart CHIEMCHAISRI and Cheema CHOMSURIN. J. of Japan Society on Water Environment, 30, 11, 617-620, 2007.
Micropollutants contained in leachates from the Nonthaburi open dump site in Thailand were investigated. The leachate contained as high as 5 mg/L of bisphenol A and 0.06 mg/L of toluene, while the concentrations of these compounds in the leachate from the Nakornpatom engineered landfill adjacent to the Nonthaburi site were between 1/100 and 1/1000 of those in the Nonthaburi site were observed for. It is suggested that the heat generated by the biodegradation of wastes promoted the release of the micropollutants from plastic wastes in the solid waste disposal site.
Factors affecting concentration of bisphenol A in leachates from solid waste disposal sites and its fate in treatment processes
ABSTRACT; T. Urase, K. Miyashita. J. of Material Cycles and Waste Management, 5(1), 77-82, 2003.
Concentrations of bisphenol A (BPA) contained in landfill leachates from solid waste disposal sites were measured. The concentrations of BPA contained in leachates from industrial waste sites were in a range of ND to 2,800 micro-g/L, while those from municipal sites were in a range of 26 micro-g/L to 8,400 micro-g/L. The leachates from ash-rich sites contained relatively lower concentrations of BPA compared with organic-rich leachates. It is suggested that BPA concentration increases with time after the completion of reclamation in the case of ash-rich sites, whereas the concentration of BPA decreases with time in the case of organic-rich sites. A seven-years survey on a site in Japan showed neither a decrease nor an increase tendency in the concentration of BPA during ongoing reclamation. A leachate from a site in the Philippines contained high concentrations of BPA. A slight positive correlation was found between BPA concentrations and TOC. A major portion of BPA in leachates was found in dissolved and organic unassociated fractions, which cannot be precipitated by coagulation. More than 99.9% of BPA contained in the raw leachates was removed by the conventional series of treatment processes consisting of biological treatment, coagulation, sedimentation, sand filtration and activated carbon adsorption.
Keywords; Bisphenol A, leachate, solid waste, landfill sites, hazardous substances.