【作者】 李刚；

【导师】 王青；

【作者基本信息】 东北大学 ， 采矿工程， 2014， 硕士

【摘要】 在矿山开采过程中,边界品位是最基本、最重要的参数之一。边界品位的选择直接影响所圈定矿体的形态及矿石储量,进而影响矿山建设、生产规模、收益、设备选择和生产寿命,同时还影响到不可再生资源的利用率。因此,边界品位是一个对矿山经济效益和社会效益有着重大影响的技术经济参数。边界品位的优化,也是矿山经营参数优化的核心内容之一。在边界品位的优化研究中,主要有三种方法,即盈亏平衡法、最大现值法和动态规划法。国内外在这三种方法的基础上,对边界品位做了很多研究,出了许多有价值的成果,但是还存在不足。在这些研究中,不管是采用盈亏平衡法,Lane法还是动态规划法都没有考虑到开采计划的变动对边界品位和最终盈利的影响。本文用动态规划法对不同的单元开采顺序的边界品位进行优化,并就每一个开采顺序的优化结果和Lane法进行比较,以此揭示不同开采顺序的最终边界品位不同；不考虑开采顺序(用Lane去)得到的边界品位,没有实现矿床开采的最大经济效益(NPV)。根据矿床的赋存条件和矿体的开采顺序将研究对象分为6个优化单元,本文所采用的两种计算方法都是以这6个优化单元为基础来进行计算。Lane法将6个单元的品位一矿量分布表合成一个,以整体进行计算,利用最大现值法的特殊模型计算可得每一年的边界品位,然后再以单个单元为对象,根据已定的开采顺序和各年的边界品位,可以在品位矿量分布表中确定每个单元的开采年限和矿石量,进而可以算得每年盈利和现值。动态规划法将这6个单元定为前后过渡的6个开采阶段,每个开采阶段包括若干个状态。开采方案从第一阶段的各状态开始一直到最后一个阶段的各个状态,在这些方案中找出使净现值最大的状态,按过渡的顺序反推回去,就得到每个阶段的最优过渡(也叫最优决策),这些最优决策组成该边界品位优化问题的最优解。利用Lane法和动态规划法先后计算不同开采顺序下的最优边界品位和最大现值。利用Lane法得到的每年边界品位为2.09%,1.86%,1.63%,1.40%,1.18%,边界品位不随开采计划的变动而变动,始终保持不变。在开采计划1→2→3→4→5→6顺序下得到的净现值为292539055.1$；改变开采顺序,在开采计划1→3→2→4→6→5顺序下得的净现值291956644.9$：在开采计划3→2→1→6→5→4顺序下得的净现值290146957.55。利用动态规划法得到开采计划1→2→3→4→5→6下的边界品位依次为1.99%、1.77%、1.62%、1.55%、1.29%、1.20%,最大净现值为294801 859.1$；开采计划1→3→2→4→6→5下的边界品位依次为1.99%、1.80%、1.70%、1.47%、1.30%、1.14%,最大净现值为2923651 93.6S：开采计划3→2→1→6→5→4下的边界品位依次为1.96%、1.94%、1.69%、1.49%、1.32%、1.12%,最大净现值为290864278.8$。当开采计划发生改变时,虽然利用Lane法得到的边界品位没有发生改变,但是净现值有明显不同,而采用动态规划法得到的边界品位和净现值发生明显改变。由刁Lane法的局限性,这里将动态规划法的最终结果做实际生产用,通过上述结果可以发现.采用1→2→3→4→5→6的开采计划得到的净现值是最大的,该方案更适合矿山。更多还原

【Abstract】 Cutoff grade is one of the most basic and important parameters in mining process. The selection of cutoff grade affects the shape of the enclosed ore-body and ore reserves directly, and then affects mine construction, scale of production, income of mine, facilities selection, and production life-span, and even utilization rate of non-renewable resource. Therefore, cutoff grade is a major impact on the technical and economic parameters both in mine economic benefits and social benefits. Cutoff grade optimization is also one of the core content in mine management parameters’ optimization.In the research of the cutoff grade, there are three main methods, the profit and loss balance method, Lane method and dynamic programming optimization method. Scholars of domestic and foreign had made many valuable achievements about cutoff grade studies, but it still exist some insufficiencies. In these studies, whether the profit and loss balance method, Lane method or dynamic programming method does not take into account the impact of the change of the mining plan on the cutoff grade and the final profit. In this paper, the cutoff grade of the mining sequence of the different unit is optimized with dynamic programming method, and comparing the optimization results of each mining sequence with the Lane method. It reveals that the final cutoff grade of the different mining sequence is different, and it can’t achieve the maximum economic benefits of the deposit mining (NPV) without consider mining sequence (Lane) boundary grade.According to the existing conditions and the mining order, the object researched is divided into six optimization units. In this paper, the two kinds of calculation methods are based on the six optimization units for the calculating. The Lane method will combine the distribution of the grade and ore of the 6 units as a table and optimize with the whole, then calculate the annual cutoff grade with the special model of the maximum of present value. Objecting with the single unit, the production life and ore quantity per unit can be determined in the grade and ore distribution list, and then the annual profit and value can be calculated according to the mining sequence and the cutoff grade. The dynamic programming method define the 6 units as 6 mining stages, every stage is before and after the transition. Each mining stage comprises several states. The mining plans contain all the plans from the each state of the first stage to the each state of the last stage. Finding out the having maximum NPV of the state in last stage and deduced by reverse sequence of the transition order, then the optimal transition (also called optimal decision) of every stage was obtained. The optimal result of this cutoff grade optimal problem was composed of all optimal decision-makings.Compute the optimal cutoff grade and maximum value with the Lane method and dynamic programming method on the conditions of the changing mining plan. Using Lane method obtaining annual cutoff grade is 2.09%,1.86%,1.63%,1.40%,1.18%, the cutoff grade keep the same even the mining plane changes. Under the mining plan of 1->2->3->4->5->6,getting the present value is 292539055. 1＄.Changing the mining plan, then under the mining plan of 1->3->2->4->6->5, the present value is 291956644.9 ＄.Under the mining plan of 3->2->1->6->5->4, the present value is 290146957.5$.Using the dynamic programming method, obtaining annual cutoff grade under the mining plan of 1_>2->3->4->5->6 is 1.99%,1.11%,1.62%,1.55%.1.29%,1.20%,the maximum value is 294801859.1$.The cutoff grade under the mining plan of 1->3->2->4->6->5 is 1.99%, 1.80%,1.70%,1.47%,1.30%,1.14%,the maximum value is 292365193.6$. The cutoff grade under the mining plan of 3->2->1->6->5->4 is 1.94%,1.69%,1.49%,1.32%,1.12%, the maximum value is 290864278.8$. When the mining plan changes, although the cutoff grade obtained by using Lane method doesn’t change, the net present value is significant different, while the cutoff grade and the net present value obtained by using dynamic programming method obviously changes. Because of the limitations of the Lane method, the final results of the dynamic programming method will be applied to the actual production. It can be discovered through the above results that the net present value obtained by using the mining plan of 1->2->3->4->5->6 is the biggest, and it is more suitable for mines.更多还原