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wood dust will be ignited, releasing heat and causing an explosion accident. Yuan et al. (2015) examined and analyzed more than 2000 dust explosion accidents that occurred worldwide between 1785 and 2012, and found that 17% of the incidents were caused by wood dust. Wood dust is an important type of combustible dust that accounts for 46% and 27% of all explosion accidents in the US and China, respectively. On January 31, 2015, a wood dust explosion occurred in Jinhe Xingan Wood-based Panel Co. Ltd., Genhe, Inner Mongolia in China killing six, injuring three, and badly damaging the factory building (State Administration of Work Safety of China 2015). According to a preliminary investigation, the accident was caused by an initial wood dust bin explosion in the sanding and dust collecting system, which led to a secondary wood dust explosion in the workshop, triggering a fire in the workshop and storehouse. Increasing attention has been paid to research on combustible dust explosions in the United States, Britain, France, Germany, Japan, Norway, and other developed countries (Nagy and Verakis 1983; Eckhoff 2005, 2009; Amyotte and Eckhoff 2010). They studied the causes and consequences of dust explosions, mechanisms of dust explosions, physical and chemical experimental methods related to dust cloud generation and combustion, explosion test parameters, and safety improvement procedures to reduce the probability and damage of dust explosions in industry. The maximum explosion pressure ( P max ), the maximum rate of explosion pressure rise (d p /d t ) max , and the explosion index ( K st ) derived from (d p /d t ) max are safety characteristic factors usually used for hazard identification in various industries, suggesting safety improvement procedures, and designing safety measures for the mitigation of destructive effects of dust explosions (BSEN 14034-1(2004) and BS EN 14034-2 (2006)). Cashdollar (2000) believed that the particle size, shape, and specific surface area of dust were closely related to its explosion characteristics. Amyotte et al. (2012) conducted a comparative study on the effects of dust particle size and shape on the maximum explosion pressure as well as the rise in the maximum rate of explosion pressure of wood fibers and polyethylene dust. They deemed that fibrillar particles such as wood dust were more likely to explode because they would remain suspended in air for a long time, increasing their ignition probability. Calle et al. (2005) also studied the explosion characteristics of wood dust with different particle size in a 20 L sphere, and confirmed that explosion violence decreases with increasing particle size. The researchers then developed a model based on balances of chemical reactions, kinetics, and thermodynamics during the explosion. Most studies on dust explosions have focused on coal, metal, and food dust. To date, the reports about wood dust explosion characteristics are still in a fragmentary stage, including the description of the individual explosion characteristics of wood dust, describing common physical laws of various dust types such as explosion incentives, explosive conditions, as well as explosion and explosion factors (Hedlund et al. 2014; Krentowski 2015). Minimal attention has been paid to the combustion and explosion dynamics in wood explosions (Calle et al. 2005; Huescar Medina et al. 2015), mainly because of the considerable variation in wood particle size and morphology, as well as the low density and large specific surface area of wood dust. The 1990s saw a rapid development of fiber board production as an effective way to comprehensively utilize wood resources in China. However, it is unavoidably accompanied by a lot of dangerous wood dust explosions. In fiberboard production, the equipment that is prone to dust explosion includes the wood fiber drying system, dry
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Guo et al . (2019 ). “Explosion of wood d usts,” B io R esources 14(2), 3182-3199.
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