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论文类型：期刊论文

发表时间：2019-12-01

发表刊物：PROCESS SAFETY AND ENVIRONMENTAL PROTECTION

收录刊物：EI、SCIE

卷号：132

页面范围：303-312

ISSN号：0957-5820

关键字：Nano-PMMA dust explosion; Explosion suppression; Flame propagations; Suppression mechanisms

摘要：Flame suppression mechanism of KHCO3 for 100 nm PMMA dust explosions was investigated experimentally and computationally. The effect of KHCO3 particle size on the suppression efficiency was examined. The study revealed that the larger the proportion of added KHCO3, the more significant the suppression effect on flame, for KHCO3 particles with a fixed particle size distribution. The suppression effects were significantly increased with the decreasing of KHCO(3 )particle size distributions. For endothermic mechanism, when the KHCO3 particles with three particle sizes were mixed with 100 nm PMMA, the heat absorption peaks exhibited at the initial stage, in which the heat absorption values were 28 J/g, 26 J/g and 21 J/g, respectively. A kinetics model was established to reveal the chemical suppression mechanism. It was presented that the mole fractions of key flame radicals (H and OH) were obviously reduced during the chain reaction processes with the addition of KHCO3. For KHCO3 particles, the formation of catalytic cycle K double left right arrow KOH converted H and OH radicals into a stable combustion product H2O, resulting in a lower flame speed and flame temperature. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.