束状孔双漏斗爆破分段采矿法研究

Study on the Sublevel Mining With Double Craters Blasting of Bunch-Holes

采用束状孔当量球形药包(ESC)漏斗爆破分层落矿,爆破落矿的分层高度为单漏斗爆破的高度,且同一炮孔中需进行多次分层爆破,可造成分层爆破顶板不平整、塌孔等问题。基于束状孔爆破理论,通过现场试验,确定漏斗爆破参数,研发了束状孔双漏斗爆破分段采矿法。该方法矿块中布置平行束状炮孔,炮孔内分上下两层布置药包。药包同时起爆,爆破方向分别指向分段采场上部的凿岩硐室及下部的临空面,实现分段采场组合爆破漏斗水平落矿。一次爆破分段的高度为两组爆破漏斗深度及间隔距离之和。分段高度14~20 m,一次崩落爆破规模达10万t级,矿石回采率≥85%,贫化率≤10%,大块率<5%,采场生产能力≥2500 t/d。该方法解决了爆破过程中炮孔破坏问题,并增加了采场一次爆破的规模,极大提高了采矿效率。

In layered blasting with bunch-holes equivalent spherical charge(ESC),the layered height is the height of a single crater,and plenty of blasting are required in the same blasting hole,which can cause problems such as uneven stope roof and hole collapse.This paper is based on the theory of bunch-holes blasting and determines the parameters of crater blasting through on-site experiments,and the sublevel mining with double craters blasting of bunch-holes(BDC)is developed.It arranges ESC craters in two layers.These charge packs are detonated simultaneously,and the blasting directions point towards the drilling chamber in the upper part and the free face in the lower part in the stope,forming a combined blasting craters for the segmented ore caving.The segmented height is the sum of the crater depths and the spacing distance of the two craters,and its height is 14~20 m.The blasting scale is about 100000 t,and the recovery rate≥85%,the dilution rate≤10%,the block rate<5%,the production rate≥2500 t/d.The method solves the problem of borehole damage during the blasting process and increases the scale of a single blasting in the mining area,greatly improving mining efficiency.