散装炸药在矿山巷道爆破掘进的应用效果分析

当前矿山巷道爆破掘进时,炮孔装填炸药多采用人工装填卷状炸药的方式,劳动强度大且作业效率不高,尤其在矿岩条件差和炮孔较深的作业环境,该方式严重影响了巷道掘进的效率,间接制约了矿山的生产能力。为此在非洲某铜矿进行散装炸药的巷道掘进爆破实验,使用井下压缩空气向水平炮孔中装填散状炸药的便携式装药设备,从炮孔布置、炸药种类和装填方式等对现行的巷道掘进工艺进行了改良。考虑巷道周边光面爆破的要求和底板积水的特点,掏槽孔和辅助孔采用散装炸药,周边孔和底孔采用卷装乳化炸药。通过改变风压来调节炮孔内的散装炸药的装药密度,经20余次实验,寻找到了较优的爆破施工方案,使该矿巷道掘进进尺成本每米节约15.4%,炮孔利用率提高到91.31%,平均单循环装药时间缩短了16.7%。同时该工艺在国内的某磷矿巷道掘进中也取得了较大的成功,其中炮孔利用率高达97%,平均单循环装药时间缩短近40%,为实现矿山巷道掘进机械化奠定了坚实的基础。

Analysis of application effect of bulk explosives in mine tunnel blasting excavation

The current mining tunnel blasting excavation,the characteristics of the method of loading and filling the explosive by manual loading are large labor intensity and low efficiency,especially in the poor ore-bearing rock condition and deep hole of the working environment,which seriously affect the excavation efficiency,the production capacity of mine is restricted indirectly.In this paper,a copper mine in Africa for bulk explosive excavation blasting test,portable charging equipment is to be used to fill the horizontal hole with a bulk explosive by using compressed air.The improvement of the existing tunneling process is carried out from the hole arrangement,the type of explosive and the loading method,considering the requirements of smooth blasting in tunnel surrounding and the characteristics of bottom water,therefore,cutting hole and auxiliary hole are used for bulk explosives,peripheral hole and bottom hole are adopted emulsion explosive with volume.By changing the air pressure to adjust the hole inside the bulk of the explosive charge density,after about 20 experiments,we found the better blasting construction scheme.At the result,the cost per meter of tunnel driving in this mine is 15.4%,the utilization factor of hole is increased to 91.31%,and the average single-cycle loading time is reduced by 16.7%.At the same time,the method has also been successful in the development of some phosphate mine roadway in China.The utilization factor of hole is up to 97%and the average single-cycle loading time is reduced by nearly 40%,which lays a solid foundation for the mechanization of tunnel excavation.