聚磷酸铵抑制PMMA粉尘爆炸特性研究

Study on suppression of PMMA dust explosion by ammonium polyphosphate

为研究聚磷酸铵(APP)对聚甲基丙烯酸甲酯(PMMA)粉尘爆炸的抑制特性,从最大爆炸压力P_(ex)、最大爆炸压力上升速率(dP/dt)_(ex)、最小点火能量(MIE)和最小点火温度(MIT)等多方面分析了APP对PMMA粉尘爆炸特性的影响。结果表明,APP可有效降低PMMA粉尘最大爆炸压力和最大爆炸压力上升速率,并延迟最大爆炸压力峰值到达时间;对于不同浓度PMMA粉尘的MIE,APP均有显著的抑制效果,且存在临界抑制浓度配比1∶1,在该浓度配比条件下PMMA粉尘很难通过静电点火;对于不同浓度PMMA粉尘的MIT,APP同样均具有一定抑制作用,且相同浓度配比条件下,抑制作用随PMMA浓度的增大而增大。此外,结合APP和PMMA热特性及红外光谱分析结果,分析了APP抑制PMMA粉尘爆炸机理。

In order to study the suppression characteristics of ammonium polyphosphate(APP)on polymethyl methacrylate(PMMA)dust explosion,the effects of APP on PMMA dust explosion characteristics were analyzed from the aspects of explosion pressure,explosion pressure rise rate,minimum ignition energy(MIE)and minimum ignition temperature(MIT).The results show that APP can effectively reduce the maximum explosion pressure and explosion pressure rise rate of PMMA dust,and delay the arrival time of explosion pressure peak.For MIE with different concentrations of PMMA dust,APP has a significant inhibition effect,and there is a critical inhibition concentration ratio of 1∶1.Under this concentration ratio,PMMA dust is difficult to ignite through electrostatic ignition.APP also has a certain inhibitory effect on MIT with different concentrations of PMMA dust,and the suppression effect increases with the increase of PMMA concentration under the condition of the same concentration ratio.In addition,combined with the thermal characteristics and infrared spectrum analysis results of APP and PMMA,the mechanism of APP inhibiting PMMA dust explosion is analyzed.The inhibition mechanism of APP on PMMA dust explosion includes physical and chemical effects.The physical effect is mainly caused by APP decomposition endothermic and delays the decomposition rate of PMMA.The chemical action is mainly due to the decomposition of APP,produces a large number of active groups that can consume the active free radicals generated in the process of PMMA explosion,which can reduce the chain reaction rate or interrupt the chain reaction,and then inhibit PMMA dust explosion.In addition,combined with the thermal characteristics of APP and PMMA and the results of infrared spectroscopy,the mechanism of APP inhibitingPMMA dust explosion was analyzed.