| Summary: | 碩士 === 國立雲林科技大學 === 環境與安全衛生工程系 === 104 === Previous biomass burning researches mostly have discussed on particle emissions rather than on gaseous emissions. This study focus on combustion emissions derived from crop residues and worship materials burnings in a controlled chamber and a field experiment. Chamber experiments conducted by an annular denuder sampler to investigate in different species ( wheat straw、corn stoves、corn leaves、joss papers and incenses) for interpreting the characteristics of emissions, included PM2.5, anhydrosugar levoglucosan, water-soluble ions, and gaseous pollutants have been examined.
The results have shown that mass concentration of PM2.5 from incense in smoldering condition was distinctively 1.2 ~ 2.7 times higher than that from crop residues and joss papers in flaming. Emissions of environmental joss paper (from bamboo material) and treated joss paper (with ethanol) demonstrated ~ 50% of PM2.5 reduction comparing to normal joss paper (from waste paper). Meanwhile, the emission of levoglucosan in fine particle from crop residues presented: wheat straw > corn leaves > corn stoves; and normal joss paper has a highest emission of levoglucosan in worship materials. For the ions, major species of PM2.5 from the crop residues were K+, Cl-, NH4+, and SO42-. Three major ions of K+, Cl- and SO42- were derived from joss paper, and F- and Ca2+ions were obtained from incense emission. For the gaseous emissions, crop residues and joss papers emitted the higher amount of HONO and H2SO4 gases, and a rich abundance of HONO and NH3 were found from incense burning. Both crop residues and worship materials presented an extremely high emission of nitrous acid (HONO) (accounted 40~80% of total gases; individually HONO 300~400 mg kg-1 from crop residues and joss papers, 100~150 mg kg-1 from incenses emissions). The results have exhibited that various burning conditions and inherent properties of biomass may affect on the emissions of HONO (such as joss paper contained a yellow azo-dye would enhance the emission of HONO). Meanwhile, this study also employed a field experiment to verify characteristics of chamber emissions. For the temple, indoor HONO concentration was obviously higher than outdoor level (Indoor/Outdoor ~ 4.4). Thus, the study has first revealed that worship materials emitted high concentration of HONO, which may affect on the health concerns of believers and neighboring residents, and it is worth to explore gaseous emissions derived from worship burning as well to interpret health impacts of indoor air.
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