Experimental Study On The Dust Combustion And Explosion Characteristics And Inerting Explosion Suppression Of Corn Starch

The grain industry in China is in a stage of rapid development,and the dust explosion is the biggest threat to the grain industry safety production.Taken corn starch as the object of experimental research,the combustion and explosion characteristics of corn starch and the inhibition of the inert dust on the corn starch explosion were studied.The 20 L sphere and dust ignition temperature measuring device were used to study effects of the dust concentration,ignition delay time,ignition energy,mass fraction of inert dust,spray pressure and other external factors on the explosion characteristics of corn starch.Meanwhile,the general rules were summarized.Conclusions are as follows:1.The influence rules of the MIT of maize starch dust cloud under external factors were studied by using G-G oven.The experiment shows that the concentration and the mass fraction of CaCO3 have highly significant affection on the MITC of maize starch.The interaction of dispersive pressure and dust concentration has significant affection on the minimum ignition temperature.Meanwhile,spray pressure have no affection on the MIT of the corn starch.2.The influence of ignition energy on the characteristics of dust explosion was analyzed.With the increase of ignition energy,the lower limit of dust explosion decreases rapidly and then remains unchanged.With the increase of mass concentration,the significance of influence of ignition energy on explosion index increased firstly and then decreased.When the mass concentration is 500g/m3,the significance is the biggest.3.The influence of ignition delay time on the explosion characteristics of corn starch is analyzed.With the increase of ignition delay time,the explosion pressure increased firstly and then decreased.With the increase of dust mass concentration,the significance of influence of ignition delay time on explosion pressure was decreased.The best ignition delay time of different mass concentrations is 80 ms.4.The effect of explosion suppression: NH4H2PO4>Na HCO3>Si O2.There is a synergistic effect between NH4H2PO4 and Na HCO3 on explosion suppression,while there is no this rule between NH4H2PO4 and SiO2.