Study On Deflagration Sensitivity Of HDPE Dust Cloud And Layer

High density polyethylene（HDPE）as a thermoplastic resin material,is widely used in various fields.However,in the production,storage,transportation and use of HDPE process will form a higher concentration of dust clouds and a certain thickness of dust layer,once encountered a certain amount of ignition source,there will be a serious dust explosion accident.Therefore,the study of HDPE dust deflagration sensitivity parameters is helpful to master its explosive law and obtain a certain theoretical basis,so as to prevent the occurrence of dust explosion accidents to provide a certain reference value.In this paper,the HDPE is viewed as the research object.Firstly,the effects of dust particle size,dust cloud concentration and dispersion pressure on the minimum ignition energy（MIE）and the minimum ignition temperature（MITc）were studied.Secondly,the effect of dust thickness on the minimum ignition temperature（MITL）of HDPE dust layer was studied.And then the effect of dust particle size and electrode spacing on the electrostatic spark sensitivity of HDPE dust were studied.Finally,the orthogonal experimental design principle was used to investigate the influence of various factors on HDPE dust deflagration sensitivity parameter.The results showed that with the increase of dust particle size from 25μm to 120μm,MIE and MITc of HDPE dust cloud increased gradually,and with the increase of dust cloud concentration and dispersion pressure,MIE and MITC of HDPE dust cloud showed the trend of decreasing first and then increasing.MITL of HDPE dust layer was higher than 400℃,which showed that the deflagration heat sensitivity of the dust layer was low.With the increase of dust particle size,the electrostatic spark sensitivity of HDPE dust decreased gradually,and with the increase of electrode spacing,the electrostatic spark sensitivity of HDPE dust increased first and then decreased.The orthogonal test of HDPE dust showed that the factors affecting MIE from strong to weak were:dust particle size>dust cloud concentration>dispersion pressure;the factors affecting MITC from strong to weak were:dust particle size>dust cloud concentration>dispersion pressure;the factors affecting the electrostatic spark sensitivity from strong to weak were:dust particle size>electrode spacing.