Research On Integrated Flexible Production Planning Of Steel Making-Continuous Casting-Hot Rolling And Its Simulation System

The integrated process of Steel Making, Continuous Casting and Hot Rolling(SM-CC-HR) is complexy, capital and energy extensive. These three processes are tightly connected. In order to save cost, improve throughput, save energy consumption and improve the power of competition of steel enterprise. The integrated production planning and scheduling of SM-CC-HR is highly desired to be solved. The function of the MES in the CIMS of Iron & Steel enterprise and the integrated planning of SM-CC-HR are reviewed firstly. Combining with the open project, research on the experiment system of integrated planning of SM-CC-HR, which is a "985 project" of the key laboratory of Integrated Automation of Process Industry (Northeastern University) of Ministry of Education. Based on the flexibility theory and the actural production process of Iron & Steel enterprise in China, Some problems existed in the integrated flexible production planning of SM-CC-HR are studied. This dissertation has mainly carried on the following researches.An overview of a new metaheuristic algorithm, the Variable Neighborhood Search (VNS), is proposed. The brief description of methaheurists is given, then, the original of VNS, the principle of VNS and the analysis of VNS are given respectively. The extensions of VNS are also proposed, and many methods to improve the VNS are proposed. The applications of improved VNS on combinational optimization and continuous optimization are also introduced; finally, the future research about VNS is proposed, including applications and improvements. The following researches are based on the above theory.In order to solve the integrated flexible charge planning, the model and algorithm of integrated flexible charge planning problem on an integrated steel plant are proposed. Considering the characteristic of flexible orders (slabs or jobs) and the integrated technical constraints of SM-CC-HR, a multiobjective optimization model is proposed with minimizing the number of charges, minimizing the operation costs and maximizing the throughput. The multiobjective optimization model is transformed into many single objective optimization models based on rule and bound objective function method. The two phase heuristic algorithm, guided variable neighborhood search combining with harmony search and simulated annealing method are proposed. To test the performance of proposed algorithms, an enumeration algorithm with complexity O(m") and many classical methaheuristics are introduced, and these algorithms are tested based on random data and actural data. The flexible solutions of integrated charge planning are abtained, including more weakly Pareto optimal solution, and based on the the flexible solutions, integrated tundish planning will be get more feasible or optimal solutions for downstream planning. Hence, the results show that the model and algorithms are effective and applicable.The model and algorithm of integrated flexible tundish planning problem based on flexible jobs are proposed. Considering the integrated flexible charge planning and the integrated technical constraints of SM-CC-HR, a multiobjective optimization model is proposed with the objectives to optimize the number of tundish, the additional cost of technical operations and the throughput balance of each flow. Combining iterated local search with Variable Neighborhood Descent (VND) search method and Reduced Variable Neighborhood Search (RVNS) method, two new hybrid metaheuristics are designed. The performance of hybrid algorithms are analyzed based on changing number of local iteration and weights of objective function, these two algorithms are also compared with heuristic method based on numeral analysis of the actual data. The results show that the model and algorithms are effective and applicable. It provides highly probability of integration to downstream planning.The model and algorithm of continuous casting batch machine scheduling with flexible jobs are proposed based on its character. Considering the integrated flexible charge planning and tundish planning, and based on the integrated technical constraints of SM-CC-HR, a mathematical model with minimizing the setup costs is proposed. Combining iterated local search with particle swarm optimization, a new hybrid algorithm is proposed. The performance analysis of hybrid algorithm is analyzed based on changing its parameters. The proposed algorithm is also compared with heuristic method based on numeral analysis of the actual data. The results show that the model and algorithms are effective. The integrated planning of SM-CC is also achieved.The model and algorithm of hot rolling batch machine scheduling are proposed. Considering the integration of SM-CC-HR. a multiobjective optimization model with minimizing the total waiting time, minimizing the total operation penalties and maximizing the average rolling length. An improved iterated local search is proposed. The performance of proposed algorithm is analyzed with changing its parameters. The proposed algorithm is also compared with heuristic method based on numeral analysis of the actual data.Based on the researches mentioned above, a simulation system of integrated planning of SM-CC-HR is developed. The results show that it can improve the production planning, decrease the production cost and save energy.