摘要:
近年工贸行业铝粉尘爆炸事故频发,严重威胁人员安全与相关行业的经济发展。为研究铝粉在工业生产除尘管道中的爆炸特性与抑爆剂对爆炸的抑制作用,搭建了中大尺度透明管道爆炸测试系统,开展了铝粉爆炸与抑爆实验。通过分析爆炸压力演化波形、燃爆火焰传播特征可知:随着铝粉浓度增大,单位体积内铝粉增多,燃烧后释放的热量增加,爆炸火焰在历经第二、三节管道后快速传播,管道内各测点的爆炸压力随之增强,同时管道外的自由场压力与压力上升速率显著升高;MgAl-CO3双金属超分子抑爆材料的化学-物理协同抑制作用可以有效抑制铝粉爆炸,当抑爆剂浓度为500 g/m3时即可降低不同浓度铝粉的爆炸自由场压力,且抑爆后的自由场压力下降率基本一致,抑爆剂对300 g/m3浓度铝粉爆炸的最大压力上升速率、火焰传播速度抑制效果优于200 g/m3浓度铝粉;当铝粉浓度为200 g/m3时,随着抑爆剂浓度的增大,抑爆效果基本维持不变,但过高浓度的抑爆剂对爆炸自由场压力的抑制效果反而降低。本文基于中大尺度测试系统,聚焦于探究工业除尘管道内一定浓度的铝粉爆炸特性及抑爆材料的抑制效果,研究结果能够为工贸行业除尘管道中铝粉尘爆炸的危险性评价与爆炸抑制提供科学依据与理论支撑。
Abstract:
In recent years, there have been frequent explosions of aluminum dust in the industrial and commercial enterprises, seriously threatening the personnel safety and economic development. To investigate the explosion characteristics of aluminum powder and the efficacy of explosion suppressant in industrial dust removal pipelines, a medium-to-large-scale transparent pipeline explosion testing system was constructed, and experiments on aluminum powder explosion and explosion suppression were carried out. Various parameters were measured under different influencing factors, including the explosion pressure, maximum free-field pressure rise rate, and the flame propagation speed. Through the analysis of pressure curves and deflagration flame propagation characteristics, the results showed that aluminum powder with a concentration below 100 g/m³ had a relatively low explosive destructive power in medium-to-large-scale pipeline. With increasing aluminum powder concentration, the mass of aluminum powder per unit volume rose. Consequently, more heat was released upon combustion. The flame propagated rapidly after passing through the second and third sections of the pipeline. The explosion pressure at each measurement point in the pipeline increased accordingly. Simultaneously, the free‑field pressure and its rise rate outside the pipeline increased significantly. A MgAl‑CO₃ bimetallic supramolecular suppressant suppresses aluminum powder explosion via physicochemical synergy. At a suppressant concentration of 500 g/m³, the free-field pressure of aluminum powder explosion decreased across all tested powder concentrations. Furthermore, the suppressant exhibited better performance for 300 g/m³ aluminum powder than for 200 g/m³, in terms of reducing both the maximum free-field pressure rise rate and flame propagation speed. At an aluminum powder concentration of 200 g/m³, the suppression effect remained almost unchanged with increasing suppressant concentration. However, an excessively high suppressant concentration reduced the suppression effect on the explosion free‑field pressure. The suppression effect of the suppressant interacts with the reaction acceleration caused by its high concentration, thereby reducing the overall suppression efficacy. Based on the engineering-scale pipeline testing system, these findings can provide scientific and theoretical support for the risk assessment and explosion suppression of aluminum powder explosions in industrial dust removal systems.