核-壳型KHCO_3/赤泥复合粉体的甲烷抑爆特性

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KHCO_3/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KHCO_3粉体的抑制效果对比。结果表明:核-壳型KHCO_3/赤泥复合粉体具有更好的抑爆效果。其中,负载含量为30%的KHCO_3/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KHCO_3/赤泥复合粉体的抑爆机理进行了讨论分析。

Suppression characteristics of KHCO3/red-mud composite powders with core-shell structure on methane explosion

The KHCO3/red-mud composite powder was successfully prepared by the anti-solvent method for gas explosion 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.