金属露天矿境界和采剥计划同时优化研究

针对露天矿境界和采剥计划单独优化得到的不是全局最优解问题,提出了境界和采剥计划同时优化方法。通过给定地表约束、帮坡角约束、采剥总量、境界增量等条件构建了一系列地质最优候选境界,对每个候选境界做采剥计划优化,以净现值最大为目标函数,得到了境界和采剥计划同时优化的最优境界。通过建立地表标高模型和矿床数值模型,以及设置帮坡角和技术经济参数约束条件,对某露天铁矿分别采用境界、采剥计划单独优化和境界、采剥计划同时优化的方法进行优化,得到单独优化时最优境界净现值为25.8亿元,同时优化时最优境界净现值为45.7亿元,实现利润净现值增加19.9亿元。结果表明:境界、采剥计划同时优化方法优于境界、采剥计划单独优化方法,能够为露天矿生产决策者提供有利的手段和可靠的参考。

Simultaneous optimization of state and mining-stripping plan for metal open-pit mine

Aiming at the problem that the separate optimization of state and mining-stripping plan for open-pit mine is not the global optimal solution, the simultaneous optimization method of state and mining-stripping plan was put forward. A series of optimal geological candidates state were constructed by the conditions of the given surface constraints, slope angle constraint, total exploitation ,boundary increment and so on, and then the mining-stripping plan of each candidate state was optimized. With the maximum NPV as the objective function, the optimal boundary of simultaneous optimization for state and mining-stripping plan was obtained. By establishing the surface elevation model and the numerical model of the deposit, and setting up the slope angle and the technical and economic parameter constraints, separate optimization method and simultaneous optimization method of state and mining-stripping plan were respectively used in the open-pit iron mine. When separately optimized, the NPV of optimal state is 2 billion 580 million yuan , and when simultaneously optimized, the NPV of optimal state is 4 billion 570 million yuan, and the NPV of profit is increased by 1 billion 990 million yuan. The results show that the simultaneous optimization is better than the separate optimization, which can provide favorable means and reliable references for the decision makers of open-pit production.