Graduate School of Medical Sciences, Kanazawa University, Kakuma-Machi, Kanazawa 920-1192, Japan.
Institute of Nature and Environmental Technology, Kanazawa University, Kakuma-Machi, Kanazawa 920-1192, Japan.
Int J Environ Res Public Health. 2022 Mar 25;19(7):3944. doi: 10.3390/ijerph19073944.
To mitigate global warming and achieve carbon neutrality, biomass has become a widely used carbon-neutral energy source due to its low cost and easy availability. However, the incomplete combustion of biomass can produce polycyclic aromatic hydrocarbons (PAHs), which are harmful to human health. Moreover, increasing numbers of wildfires in many regions caused by global warming have greatly increased the emissions of PAHs from biomass burning. To effectively mitigate PAH pollution and health risks associated with biomass usage, the concentrations, compositions and influencing factors of PAH emissions from biomass burning are summarized in this review. High PAH emissions from open burning and stove burning are found, and two- to four-ring PAHs account for a higher proportion than five- and six-ring PAHs. Based on the mechanism of biomass burning, biomass with higher volatile matter, cellulose, lignin, potassium salts and moisture produces more PAHs. Moreover, burning biomass in stoves at a high temperature or with an insufficient oxygen supply can increase PAH emissions. Therefore, the formation and emission of PAHs can be reduced by pelletizing, briquetting or carbonizing biomass to increase its density and burning efficiency. This review contributes to a comprehensive understanding of PAH pollution from biomass burning, providing prospective insight for preventing air pollution and health hazards associated with carbon neutrality.
为了缓解全球变暖并实现碳中和，由于成本低且易于获取，生物质已成为一种广泛使用的碳中和能源。然而，生物质的不完全燃烧会产生多环芳烃（PAHs），对人体健康有害。此外，由于全球变暖，许多地区的野火数量不断增加，大大增加了生物质燃烧产生的 PAHs 排放。为了有效缓解与生物质使用相关的 PAH 污染和健康风险，本综述总结了生物质燃烧产生 PAH 的浓度、组成和影响因素。研究发现，开放式燃烧和炉灶燃烧会产生高浓度的 PAH，其中二至四环 PAHs 的比例高于五至六环 PAHs。基于生物质燃烧的机理，具有较高挥发分、纤维素、木质素、钾盐和水分的生物质会产生更多的 PAHs。此外，在高温或供氧不足的情况下在炉灶中燃烧生物质会增加 PAH 的排放。因此，通过将生物质颗粒化、压块或碳化来增加其密度和燃烧效率，可以减少 PAH 的形成和排放。本综述有助于全面了解生物质燃烧产生的 PAH 污染，为预防与碳中和相关的空气污染和健康危害提供了前瞻性的见解。
