超细CaCO3惰化剂对铝合金抛光伴生粉尘爆炸的防控效果*

为探究超细粉体惰化剂对铝合金抛光伴生粉尘爆炸特性的影响规律，利用标准化实验装置及自行搭建的实验平台，在对爆炸基本参数进行测试的基础上，分别研究超细CaCO3粉体对抛光废弃物粉尘点燃敏感度的钝化作用以及对爆炸火焰传播进程的惰化效果，并在相同条件下与同等粒径高纯度铝粉的实验效果进行比对。研究结果表明:铝合金抛光废弃物粉尘最小点火能量为280 mJ，而同等粒径高纯度铝粉最小点火能量为35 mJ；在铝合金抛光废弃物粉尘质量浓度为300 g/m3条件下，发生爆炸的火焰传播速度峰值为7.4 m/s，约为高纯度铝粉的57%，铝合金抛光废弃物粉尘的爆炸敏感度及猛烈度均低于高纯度铝粉；当超细CaCO3粉体的惰化比为30%时，可将铝合金抛光废弃物粉尘的最小点火能量钝化至约1 J，爆炸火焰失去持续传播能力，惰化作用效果充分显现。

Prevention and control effect of ultrafine CaCO3 inerting agent on dust explosion associated with aluminum alloy polishing

In order to study the influence of ultrafine powder inerting agent on the explosion characteristics of dust associated with aluminum alloy polishing,the standardized experimental equipment and self-designed experimental platform were used to test the basic explosion parameters.The passivation effect of ultrafine CaCO3 powder on the ignition sensitivity of polishing waste dust and the inerting effect on the propagation process of explosion flame were studied respectively,and the experimental results were compared with those of high purity aluminum powder with similar particle size under the same conditions.The results showed that the minimum ignition energy of aluminum alloy polishing waste dust was 280 mJ,and the minimum ignition energy of high purity aluminum powders with similar particle size was 35 mJ.When the mass concentration of aluminum alloy polishing waste dust was 300 g/m3,the peak flame propagation velocity of explosion was 7.4 m/s,which was about 57% of that of high purity aluminum powder.Both the explosion sensitivity and intensity of aluminum alloy polishing waste dust were lower than those of high purity aluminum powder.When the inerting ratio of ultrafine CaCO3 powder was 30%,the minimum ignition energy of aluminum alloy polishing waste dust could be passivated to about 1 J,the explosion flame lost its continuous propagation ability,and the inerting effect was fully demonstrated.