Optimization Methods And System Development For Batching Planning In Steelmaking And Continuous-Casting Process

The batching problems for steelmaking and continuous-casting processes is one of the key issues about Production planning and scheduling organization in an integrated iron and steel enterprise.Quality of batching planning have a direct impact on logistics smooth of steelmaking and continuous-casting processes,production efficiency of the production line,slab production quality and therefore on cost of production.In addition,it is related to the normal operation of hot rolling production.Developing a model-based optimization system for batch planning of steelmaking continuous casting processes,can improve planning efficiency and program quality,at the same time,It is of great significance to reduce production costs,improve production efficiency and resource utilization,and enhance the core competitiveness of enterprises.In this thesis,based on a software company in Shanghai advanced order planning scheduling projects,Based on the research of steelmaking-continuous casting production process,steelmaking and continuous casting batch planning procedures and process constraints.This thesis divides the batch planning problem into two problems:the charge batching problem and the cast batching problem.Aiming at the problem of charge batching problem,a mixed integer programming model with the minimum number of charges and the minimum open ordered slabs which are not associated with customer orders is considered.Aiming at the problem of cast batching problem,a mixed integer programming model with the minimum numbers of casts and minmum the number of the times of width adjustments and maximized the utilization of tundishes is established.Because of the charge plan and the plan are all NP-hard problems.When the slab size is large,it is difficult to solve with an accurate algorithm.Therefore,the heuristic algorithm and the optimization algorithm based on variable neighborhood search are designed respectively for the problem of charge plan and the cast plan.The correctness of the model and the effectiveness of the algorithm are verified by field data test.Finally,for steelmaking-continuous casting process with batch plan optimization algorithm as the core of steelmaking continuous casting batch planning optimization system is developed,the main features include:basic data maintenance,batch planning making,planning visual display and so on,The automatic preparation of the steelmaking continuous casting batch plan has played a good supporting role in the production decision of the enterprise.