化工学报2023，Vol.74Issue(10)：4352-4366,15.DOI:10.11949/0438-1157.20230915
聚磷酸铵对聚乙烯粉尘爆炸特性及热解动力学影响研究
Study on the effect of ammonium polyphosphate on the explosion characteristics and pyrolysis kinetics of polyethylene dusts
摘要
Abstract
In order to reduce the harm caused by polyethylene(PE)dust explosion accidents,a 20-L explosion ball and a self-built dust deflagration flame propagation test system were used to conduct explosion suppression experiments.The suppressive effects of ammonium polyphosphate(APP)are examined by evaluating pressure and flame propagation behavior.A synchronous thermal analyzer assesses APP's impact on the thermal decomposition of PE dust.The reaction kinetics of PE and a mixture of APP and PE(I=1.0)during the rapid pyrolysis phase were derived employing the Coats-Redfern method.Through an in-depth analysis of explosion overpressure,flame propagation,thermal decomposition,and explosion by-products,it becomes evident that APP confers a synergistic explosion suppression effect on PE dust's gas and condensed phases.The findings illustrate that APP markedly diminishes PE dust's maximum explosion pressure Pmax,maximum explosion pressure rate of rise(dP/dt)max,and flame propagation speed.When the inhibition ratio was 1.0,the pressure peak vanished,indicating complete suppression of PE dust.Additionally,pyrolysis characteristics indicated that APP introduction attenuates PE dust's pyrolysis rate and postpones pyrolysis and oxidation events.Pyrolysis kinetics model analysis showed that PE dust adheres to the A3 model during rapid pyrolysis,while it transitions to the R2 model with APP addition,with corresponding average activation energies of 137.34 kJ/mol and 228.52 kJ/mol.Significantly,APP integration results in a pronounced rise in PE's apparent activation energy,highlighting the deceleration of PE particles'oxidative pyrolysis.Employing FTIR analyses,a pronounced reduction in the characteristic—CH2 and—OH peaks with APP was discerned.It's elucidated that APP provides synergistic explosion inhibition effects in both the gas and condensed phases,primarily by curtailing free radicals via phosphorus-volatile release during pyrolysis and fostering a porous,dense surface carbon layer to inhibit deflagration.These insights lay the groundwork for the development of superior powder explosion suppressants specific to PE dust.关键词
粉体/爆炸/火焰传播/聚乙烯/聚磷酸铵/热解特性/动力学Key words
dust/explosion/flame propagation/polyethylene/ammonium polyphosphate/pyrolysis characteristics/kinetic分类
资源环境引用本文复制引用
江丙友,丁大伟,苏明清,鲁昆仑..聚磷酸铵对聚乙烯粉尘爆炸特性及热解动力学影响研究[J].化工学报,2023,74(10):4352-4366,15.基金项目
安徽省高校杰出青年基金项目(2022AH020057) （2022AH020057）
国家自然科学基金项目(52074012) （52074012）
安徽理工大学研究生创新基金项目(2022CX2025) （2022CX2025）
