GAS EMISSION ASSESSMENT IN SEROPEDICA LANDFILL – RIO DE JANEIRO, BRAZIL

摘要

This study aims to quantify the emission of greenhouse gases (GHG) and organic volatile monoaromatic compounds (BTEX) by the cover layer of Seropedica Landfill in Rio de Janeiro, as well as measure the concentration of these gases in the atmosphere above the landfill cells. For this study we used two flow chambers of 0.66 m~2 and 33.2 L, which operated for 15 minutes. GHGs were sampled using 60 mL polypropylene syringes every 5 minutes, BTEX samples were collected using a flow chamber with 1.0 m~2 and 50 L at 0.7 L min~(-1), using coconut shell charcoal double-bed cartridges. GHGs and BTEX samples were also collected directly from the ambient air atmosphere. BTEX samples were analyzed by gas chromatography with mass spectrometry and GHGs by multiple detectors. The emission rates observed for methane varied from 0.1 to 714 mg m~(-2) min~(-1), for carbon dioxide between 0.2 and 148.3 g m~(-2) min~(-1) and the concentration in the atmosphere from 2.1 to 144 ppm, and 408 to 557 ppm, respectively. BTEX average emission rate were 0.0, 0.032, 0.012, 0.023 and 0.011 μg m~(-2) m~(-1), respectively for benzene, toluene, ethyl benzene, m+p-xylene and o-xylene. For the samples collected in the atmosphere, benzene concentrations were not observed above the detection limit of the method. The average concentrations of toluene, ethyl benzene, m+p-xylene and o-xylene were 2.03, 1.06, 0.10 and 0.49 μg m~(-3), respectively.