【摘要】 西石门铁矿北区新探矿体为缓倾斜破碎的厚—中厚矿体,地压显现严重,属于极度难采矿体。矿山采用无底柱分段崩落法开采,受矿体倾角和厚度限制,开采中损失贫化较大。为制定损失贫化控制措施,在研究矿石散体流动规律、矿岩冒落规律和损失贫化发生过程的基础上,根据垂直方向上回采分段数量的差异将矿体划分为不同开采区域,分别制定了损失贫化控制措施。针对3个分段的回采区域,因其贫化会较大,主要制定的贫化控制措施是实行当次废石混入率与单一步距总的放出量2项指标控制的低贫化放矿;针对小于3个分段的回采区域,若矿石被崩入空区,由于下部分段无回收条件,损失会较大,需控制损失,可采用双进路同步距回采的方式,促使矿岩快速冒落形成覆岩下放矿条件,减少崩入空区矿石量;另外总结了回采过程中脊部存留矿石问题的处理措施。这些措施在西石门铁矿北区新探矿体开采过程中得以应用,损失率为16.34%,贫化率为22.51%,效果良好。更多还原

【Abstract】 The new prospected ore-body in the northern area of Xishimen Iron Mine is a gently inclined and fractured thick-medium orebody with serious ground pressure,which is extremely difficult to be mined. The pillarless sublevel caving method is adopted in the mine. With limitation of dip angle and thickness of ore body,the loss and dilution rates are relatively high in the mining. In order to formulate control measures for ore loss and dilution,on the basis of studying the law of ore bulk flow,the law of caving and the occurrence process of loss and dilution,the ore body is divided into different mining areas according to the difference of the number of mining segments in vertical direction. So the measures for controlling ore loss and dilution are formulated respectively. Aiming at the mining area of three sections,the dilution control measures are mainly formulated due to higher dilution. The low dilution ore drawing are controlled by two indicators of the mixing rate of waste rocks and the total discharge amount of single step. For the mining area of smaller than three sections,and once the ore is caved into the goaf,resulting in higher loss rate due to the unconditional recovery of the lower section. Therefore,this loss need to be controlled. The double-way synchronous-distance mining can promote the rapid caving of ore and rock and form the ore-drawing condition of overlying strata to reduce the amount of ore caved into the goaf. In addition,the measures to deal with the problem of retained ore in the ridge during the mining process are summarized. These measures have been applied in the mining process of the new prospected body in the northern area of Xishimen Iron Mine with good effect of the loss rate 16.34% and the dilution rate 22.51%.更多还原