A Hybrid Simulation and Optimization Approach towards Truck Dispatching Problem in Surface Mines

  • Author / Creator
    Moradi Afrapoli, Ali
  • This PhD thesis has two main objectives. The first objective is to develop, implement, and verify an integrated simulation and optimization framework to study surface mining operations to address important drawbacks of currently available surface mining simulation models. These drawbacks include 1) the treatment of stochastic variables as deterministic ones in material handling systems in surface mines; 2) the deficiency in linking mining systems to mineral processing systems; 3) the inability to integrate fleet management systems with material handling systems; and 4) the lack of flexibility in using different truck-dispatching algorithms in developed simulation systems.The second objective of this research is to develop, implement, and verify efficient truck-dispatching decision-making models that can cover important drawbacks in truck-dispatching models used in currently available mining fleet management systems as well as models presented in the literature. These drawbacks include 1) neglecting important objectives like meeting the goal of the upper stage; 2) ignoring the importance of one side of a fleet (either shovels or trucks) when making optimal decisions; and 3) treating stochastic variables as deterministic ones.The integrated simulation and optimization framework was developed using three different types of software. Rockwell Arena was used as simulation modeling software to simulate mining and processing operations. IBM CPLEX was used as optimization modeling software to create a platform to implement the truck-dispatching models. These models include a benchmark model and three new models to solve the truck-dispatching problem in surface mines. The three developed models are multiple objective goal programming model, stochastic mixed integer linear programming model, and fuzzy linear programming model. Microsoft Excel was used as a datafile for the integrated framework to store all required operational data and the production schedule.The integrated simulation and optimization framework was implemented in an iron ore case study for verification purposes. The framework mimics the mining operation of the case study and interaction of the mining operation with the mine’s processing plants and fleet management system. The backbone algorithm of Modular Mining DISPATCH was used as the benchmark fleet management system to evaluate the truck-dispatching models that were developed. A comparison of the implementation of three developed models with the benchmark model in 26 scenarios of single truck-type fleets and multiple truck-type fleets shows that the developed models need an average of 16.5% fewer trucks to meet production requirements.

  • Subjects / Keywords
  • Graduation date
    Spring 2019
  • Type of Item
  • Degree
    Doctor of Philosophy
  • DOI
  • License
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