Research On Optimization Of Open Pit Limit Based On Integer Programming Method

Mining industry plays an irreplaceable role in the development of national economy.Open pit mining occupies a large proportion in the form of mining.In this thesis,two problems related to open pit mine are studied.The first is the Ultimate Pit Limit Problem,which is simply called the UPIT problem.The initial overall design of long-term planning for open pit mining is provided by it.The second is the Constrained Pit Limit Problem,which is simply called the CPIT problem.It is usually called the Open Pit Mine Production Scheduling Problem.The overall economic benefits of open pit mining are determined by it.To solve the UPIT problem,a hierarchical iterative method is proposed in this thesis.According to block number in the data set,an index sequence is generated to guide the block to be hierarchically divided according to its three-dimensional coordinate values.In order to eliminate variables,the hierarchical iterative method is used according to the hierarchy,so that the scale of the problem is reduced to a certain extent.The program is written in Python language and CPLEX solver is called by Python to solve the problem.Examples show that this method is particularly effective for solving large-scale and extra-large-scale UPIT problems,and the optimal solution of the problem is obtained.At the same time,it provides a general and accurate method for this problem and its related problems.For the CPIT problem,a methodological system is proposed in this thesis.For small and medium-scale CPIT problems,a strategy system of solving by stages is proposed.The resource quantity of each period is limited,and the whole production planning problem is solved one by one according to the period.For large-scale CPIT problems,a variable elimination method based on a new block aggregated method is proposed in this thesis.Firstly,the blocks are aggregated to reduce the number of variables and constraints in the mathematical model,and then staging strategy is used to solve the problem.Examples show that the objective function value of the methodology system proposed for the CPIT problem is better than that of the standard test set to a large extent,and the technical difficulties of solving large-scale CPIT problems are also effectively solved.In order to facilitate the popularization and application of the method,the proposed methodological system for two problems is encapsulated in this thesis,and the visualization of the results is realized.In this thesis,Qt Designer is used to design GUI,PyInstaller is used to pack programs,and a preliminary open pit mine limit optimization system is established.