Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): Emissions of particulate matter from wood and dung cooking fires, garbage and crop residue burning, brick kilns, and other sources

Abstract

Abstract.The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) characterized widespread and 20 under-sampled combustion sources common to South Asia, including brick kilns, garbage burning, diesel and gasoline generators, diesel groundwater pumps, idling motorcycles, traditional and modern cooking stoves and fires, crop residue burning, and a heating fire. Fuel-based emission factors (EF; with units of pollutant mass emitted per kg of fuel combusted) were determined for fine particulate matter (PM 2.5 ), organic carbon (OC), elemental carbon (EC), inorganic ions, trace metals, and organic species. For the forced draught zig-zag brick 25 kiln, EF PM2.5 ranged 12-19 g kg -1 with major contributions from OC (7%), sulfate expected to be in the form of sulfuric acid (31.9%), and other chemicals not measured (e.g., particle bound water). For the clamp kiln, EF PM2.5 ranged 8-13 g kg -1 , with major contributions from OC (63.2%), sulfate (20.8%), and ammonium (14.2%). Our brick kiln EF PM2.5 values may exceed those previously reported, partly because we sampled emissions at ambient temperature after emission from the stack or kiln allowing some particle-phase OC and sulfate to form from 30 gaseous precursors. The combustion of mixed household garbage under dry conditions had an EF PM2.5 of 7.4 ± 1.2 g kg -1 , whereas damp conditions generated the highest EF PM2.5 of all combustion sources in this study, reaching up to 125 ± 23 g kg -1 . Garbage burning emissions contained relatively high concentrations of polycyclic aromatic compounds (PAHs), triphenylbenzene, and heavy metals (Cu, Pb, Sb), making these useful markers of this source. A variety of cooking stoves and fires fueled with dung, hardwood, twigs, and/or other biofuels were ), while biogas had no detectable PM emissions. Idling motorcycle emissions were evaluated before and after routine servicing at a local shop, which decreased EF PM2.5 from 8.8 ± 1.3 g kg -1 to 0.71 ± 0.45 g kg -1 when averaged across five motorcycles. Organic species analysis indicated that this reduction in PM 2.5 was largely due to a decrease in emission of motor oil, probably from the crankcase. The EF and chemical emissions profiles developed in this 10 study may be used for source apportionment and to update regional emission inventories.

Municipal solid waste and dung cake burning: discoloring the Taj Mahal and human health impacts in Agra

“…Christian et al [29] found emission factors of OC=5.3 (±4.9) and BC=0.65 (±0.27) g kg −1 burned. These emission factors are within the reported range of 0.04-9.97 g BC kg −1 burned from recent measurements of trash burning in Nepal where some samples were enriched for specific compositions of plastic and foil [31], but lower than the reported range of 8.4-73.9 g OC kg −1 burned. MSW emissions can vary significantly and have high uncertainties due to the composition of the waste and stage of combustion [13,32].…”

Black Carbon, Organic Carbon, and Co-Pollutants Emissions and Energy Efficiency from Artisanal Brick Production in Mexico

“…Both the "zig-zag" and clamp kilns measured by Stockwell et al (2016) in Nepal also used coal as fuel. Jayarathne et al (2017) recently reported the particle-phase results of the same kilns measured by Stockwell et al (2016). Of these studies, Stockwell et al (2016) and Christian et al (2010) report fuel-based energy factors whereas Rajarathnam et al (2014) and Weyant et al (2014) report energy-based emission factors, allowing a proper inter-comparison with our results.…”

Chemical characterization of biomass burning and sea spray aerosol

“…5,17 Soot, polycyclic aromatic hydrocarbons (PAHs), transition metals and endotoxins have low atmospheric abundance, but are capable of contributing adverse health effects. 5,17,25,27,[50][51][52] However, certain emissions from particular sources like exhaust smoke of plastic and tire burning, welding, coke-oven, aluminum smelting, diesel and gasoline engines contain harmful species such as PAHs and trace metals. [53][54][55][56] Therefore, the chemical composition of PM is expected to be an important determinant in its health outcome and useful for setting up occupational exposure limits and human exposure studies.…”

“…[94][95][96][97][98][99][100] However, up-todate only few studies have focused on comprehensive measurements of both gas-phase and particulate-phase emissions. 50,96,98,100 Further, EFs of biomass burning PM is highly dependent on fuel type (soft wood, hard wood, grass, organic soil), fuel moisture content and burning condition (flaming vs smoldering). 94,98,101 Thus, more studies are needed to understand the emission variation of PM under different burning conditions.…”

“…72 My studies were also focused on chemical characterization of PM emitted from understudied emission sources in Nepal (e.g cookstoves, motorcycles, garbage burning, brick kilns). 50,96 Apart from primary source-aerosol characterization, I contributed to sample and analyze secondary organic aerosols, tire burning smoke, and bioaerosols in Iowa 17,18,27,56 and secondary organic aerosol in Centreville, Alabama. 106 Finally, these research work will help to fill certain knowledge gaps exist in current literature.…”