核-壳型KHCO3/赤泥复合粉体的甲烷抑爆特性

摘要

为了获取新型经济、环保、高效的粉体抑爆材料,以制铝工业废料赤泥为原料加以改性作为载体,采用反溶剂-溶析法制备出具有核-壳结构的KHCO3/赤泥复合粉体.通过20 L球形抑爆实验系统,测试新型复合粉体对甲烷爆炸压力参数的影响,并与单一赤泥粉体和KHCO3粉体的抑制效果对比.结果表明:核-壳型KHCO3/赤泥复合粉体具有更好的抑爆效果.其中,负载含量为30％的KHCO3/赤泥复合粉体使9.5％的甲烷-空气预混气体的爆炸最大压力降低37.5％,最大升压速率降低93.2％,爆炸延迟时间大幅度延长.并对核-壳型KHCO3/赤泥复合粉体的抑爆机理进行了讨论分析.%The KHCO3/red-mud composite powder was successfully prepared by the anti-solvent method for gas explo sion suppression.The aluminum industry solid waste red mud was used as the support,and the traditional suppressant KHCO3 was used as the active species.The as-prepared samples were analysized by the techniques of XRD,TG-DSC,SEM,TEM.The analysis results indicated that the composite powder possesses the special core-shell structure,which has an impact on inhibitory property.The suppression property of the as-prepared sample for CH4 explosion was tested by a 20 L spherical explosion experimental system.The results show that the potassium bicarbonate/red mud composite powder has better suppression property than that of pure red mud or pure potassium bicarbonate.The explosion pressure of 9.5％ methane-air premixed gases was reduced by 37.5％ with 30％ loaded content.The maximum value of pressure rising rate was reduced by 93.2％,and the sensitive period of the explosion was extended from 25 to 250 ms.The explosion suppression mechanism of this potassium bicarbonate/red-mud composite powder was also investigated.