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Emission Characteristics of Particulate Matter and Volatile Organic Compounds in Cow Dung Combustion
Park, Duckshin,Barabad, Mona L.,Lee, Gwangjae,Kwon, Soon-Bark,Cho, Youngmin,Lee, Duckhee,Cho, KiChul,Lee, Kiyoung American Chemical Society 2013 Environmental science & technology Vol.47 No.22
<P>Biomass fuel is used for cooking and heating, especially in developing countries. Combustion of biomass fuel can generate high levels of indoor air pollutants, including particulate matter (PM) and volatile organic compounds (VOCs). This study characterized PM and VOC emissions from cow dung combustion in a controlled experiment. Dung from grass-fed cows was dried and combusted using a dual-cone calorimeter. Heat fluxes of 10, 25, and 50 kW/m<SUP>2</SUP> were applied. The concentrations of PM and VOCs were determined using a dust spectrometer and gas chromatography/mass spectrometry, respectively. PM and VOC emission factors were much higher for the lower heat flux, implying a fire ignition stage. When the heat flux was 50 kW/m<SUP>2</SUP>, the CO<SUB>2</SUB> emission factor was highest and the PM and VOC emission factors were lowest. Particle concentrations were highest in the 0.23–0.3 μm size range at heat fluxes of 25 and 50 kW/m<SUP>2</SUP>. Various toxic VOCs, including acetone, methyl ethyl ketone, benzene, and toluene, were detected at high concentrations. Although PM and VOC emission factors at 50 kW/m<SUP>2</SUP> were lower, they were high enough to cause extremely high indoor air pollution. The characteristics of PM and VOC emissions from cow dung combustion indicated potential health effects of indoor air pollution in developing countries.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/esthag/2013/esthag.2013.47.issue-22/es402822e/production/images/medium/es-2013-02822e_0003.gif'></P>
Duckshin Park,Keun Yul Yang,ona L. Barabad,Youngmin Cho,Wootae Jeong,Soon-Bark kwon,Kiyoung Lee 한국폐기물자원순환학회 2013 한국폐기물자원순환학회 학술대회 Vol.2013 No.2
This study characterized PM and VOC emissions from cow dung combustion in a controlled experiment. Dung from grass-fed cows was dried and combusted using a dual cone calorimeter. Heat fluxes of 10, 25, and 50 kW/m² were applied. The concentrations of PM and VOCs were determined using a dust spectrometer and gas chromatography/mass spectrometry, respectively. PM and VOC emission factors were much higher for the lower heat flux, implying a fire ignition stage. When the heat flux was 50 kW/m², the CO₂ emission factor was highest and the PM and VOC emission factors were lowest. Particle concentrations were highest in the 0.23-0.3-μm size range at heat fluxes of 25 kW/m² and 50 kW/m². Various toxic VOCs including acetone, methyl ethyl ketone, benzene, and toluene were detected at high concentrations. Although PM and VOC emission factors at 50 kW/m² were lower, they were high enough to cause extremely high indoor air pollution. The characteristics of PM and VOC emissions from cow dung combustion indicated potential health effects of indoor air pollution in developing countries.
Generation Characteristics of Nanoparticles Emitted from Subways in Operation
Lee, Yongil,Choi, Kyomin,Jung, Wonseog,Versoza, Michael E.,Barabad, Mona Loraine M.,Kim, Taesung,Park, Duckshin [Chinese Association for Aerosol Research in Taiwa 2018 Aerosol and air quality research Vol.18 No.9
<P> In this study, measurements were carried out to identify the generation characteristics of wear particles emitted under a subway cabin during operation. Along with a fast mobility particle sizer, probes were installed under a subway cabin and in a subway tunnel to measure the size distributions of nanoparticles at 1-s intervals. Based on the particle density measured under the cabin minus that measured in the tunnel, the size distribution of wear particles generated under the cabin during deceleration was estimated to be bimodal at 165.5 nm and 6.98 nm. These particles were most likely generated from wheel-rail contact, as the train utilized electric braking (no mechanical force applied). In addition, a change in the wear mechanism appears to have arisen due to the increased temperature of the wheel-rail contact while nanoparticles were being emitted, leading to an initial generation of 165.5-nm particles followed by 6.98-nm particles 1 s later. </P>