Production Scheduling Of Steelmaking And Continuous Casting With Multiple Process Routes

The process of steelmaking and continuous casting(SCC)is the core process of modern iron and steel industry.And the production of multi-species,small batch and complicated routes has been seen everywhere.For SCC production scheduling problem with multi-buffer,multi-parallel machine and multi-routes,the study of efficient and stable production scheduling method can ensure the continuity and stability of the production rhythm effectively,which helps to improve the production efficiency and reduce energy consumption,thereby enhancing the competitiveness of iron and steel enterprises.For SCC production scheduling problem with the multi-parallel machine and finite buffer unit,a hybrid integer linear programming optimization model with minimizing maximum completion time is established based on continuous time representation method.Then an improved teaching and learning based optimization algorithm(ITLBO)with self-learning phase is designed to solve this problem.In ITLBO,the coding method of random keys and two-phase decoding method is used to guarantee the diversity of the search space.For limited buffer constraint,a conflict digestion mechanism is proposed based on minimum moving distance mechanism and used in decoding where the limited buffer constraint is not satisfied.For the single process route and the multi-process route SCC scheduling problem,better results can be obtained by using the above decoding method,which shows the versatility of the decoding method.Finally,considering the multi-routes SCC scheduling problem with unparalleled machines,a number of different sizes of cases are designed according to the actual production data,the effectiveness and superiority of ITLBO are verified completely through the comparison of the mean and optimal solution with other two algorithms.