爆炸与冲击2023，Vol.43Issue(12)：139-153,15.DOI:10.11883/bzycj-2023-0058
微米/纳米PMMA粉尘爆炸抑制过程中压力特性与热化学动力学的相关性
Correlation between pressure characteristics and thermochemical kinetics during suppression of micro/nano PMMA dust explosion
摘要
Abstract
To reveal the explosion suppression mechanism of micron/nano polymethyl methacrylate(PMMA)dusts,the synchronous thermal analyzer and the 20-L explosion test device were used to test the pyrolysis oxidation characteristics and the explosion overpressure evolution characteristics of micro/nano PMMA dust under the intervention of NaHCO3.Coats-Redfern method was used to calculate the kinetic parameters for the rapid pyrolysis of 30 μm and 100 nm PMMA and micro/nano mixtures,and the correlation between pressure characteristics and thermochemical kinetics during suppression of micro/nano PMMA dust explosion was analyzed,and then the suppression mechanism of dust explosion based on thermochemical kinetics was discussed by establishing the physical model of suppression mechanism of NaHCO3 on micro/nano PMMA dust explosions.The results show that the pyrolysis oxidation processes of 30 μm and 100 nm PMMA dusts are suppressed by NaHCO3,and the apparent activation energy and pre-exponential factor are increased.The maximum explosion pressure and the maximum explosion pressure rise rate of both micro-and nano-PMMA dusts are decreased obviously.In the pyrolysis stage of the mixture system,the suppression effect of NaHCO3 is mainly dominated by physical suppression,including the cooling effect of both pyrolysis reaction and products as well as the dilution effect on the concentration of combustible reactant.In the oxidation stage of the mixture system,the suppression effect of NaHCO3 is mainly dominated by chemical suppression.The free radicals are absorbed by the active groups NaOH,forming the Na↔NaOH suppression cycle.And for explosion suppressant,the smaller the particle size and the larger the adding mass ratio,the greater the apparent activation energy E of explosion mixture system,and the more significant the suppression effect.It is worth noting that compared with the maximum explosion pressure,the sensitivity of explosion pressure rise rate to the E increment of explosion mixture system is great,and nano-PMMA dust is more sensitive to the E increment of explosion mixture system than micro-PMMA dust,and the corresponding suppression effect of NaHCO3 on nano-PMMA dust is more significant.关键词
粉尘爆炸/抑爆机理/热化学动力学/爆炸强度/相关性Key words
dust explosion/explosion suppression mechanism/thermochemical kinetic/explosion intensity/correlation分类
数理科学引用本文复制引用
郭瑞,李南,张新燕,张延松,徐畅,张公妍,赵兴,解雨萱,韩喆林..微米/纳米PMMA粉尘爆炸抑制过程中压力特性与热化学动力学的相关性[J].爆炸与冲击,2023,43(12):139-153,15.基金项目
国家自然科学基金(51904170,51974179) （51904170,51974179）
山东省自然科学基金(ZR2018BEE006,ZR2019MEE118) （ZR2018BEE006,ZR2019MEE118）
