Study On Characteristics And Mechanism Of APP Inhibiting PMMA Dust Explosion

Polymethyl Methacrylate(PMMA)is a kind of high molecular compound with excellent performance,which is widely used,but it will produce a lot of dust in the processing process,which has the potential safety hazard of explosion.In order to reduce the harm caused by PMMA explosion,an efficient phosphorus nitrogen synergistic flame retardant Ammonium Polyphosphate(APP)is selected for PMMA dust explosion experiment.Through the study of explosion overpressure,minimum ignition temperature,minimum ignition energy and explosion flame,the explosion suppression efficiency of APP on PMMA dust is evaluated,its explosion suppression mechanism is revealed,and its inhibition efficiency is compared with the traditional explosion inhibitor ABC dry powder.The main work carried out is as follows:(1)The effects of APP on the maximum explosion pressure,MIT,MIE and flame propagation characteristics of PMMA dust are experimentally studied.The results show that APP has a significant inhibitory effect on the above parameters,and the inhibitory effect increases with the increase of APP concentration.(2)The explosion suppression characteristics of APP and ABC are compared and analyzed.It is found that the inhibition effect of APP on PMMA dust is better than ABC dust under the same concentration.In addition,adding a small amount of ABC dust will promote PMMA dust explosion and improve its explosion characteristics.(3)The influence of APP concentration ratio on PMMA dust explosion characteristics is analyzed.The results show that for different concentrations of PMMA dust,when the ratio of APP to PMMA dust concentration reaches 1:2,with the increase of PMMA dust concentration,the increase of maximum explosion pressure and MIE increases and then decreases,and MIT fluctuates and increases.In addition,when the ratio of APP to PMMA dust concentration is 1:1,PMMA dust measured by pipeline test device and MIE test device is not ignited.(4)The inhibition mechanism of APP on PMMA dust is analyzed from two aspects of physical inhibition and chemical inhibition,and the similarities and differences between ABC and APP in inhibition mechanism are revealed.The experimental research results can provide a theoretical basis for the prevention and control of PMMA dust explosion disaster,and can provide reference for other dust explosion prevention and control.