Multi-objective optimization of scrap steel electric furnace SCC scheduling considering CO2 emission and minimization of maximal heat waiting time

Under the carbon emission reduction policy, iron and steel enterprises are faced with huge pressure of carbon emission reduction. In the process of melting scrap steels using electric furnaces, the heats (jobs) are always assigned with different processing routes, and types of the parallel electric furnaces at each production stage are usually different. First, combining these characteristics, a model considering carbon emission and minimization of maximal heat waiting time for multi-objective optimization of scrap steel electric furnace steelmaking and continuous casting (SCC) scheduling is built. Three objectives, i.e. carbon emission, maximal heat waiting time and makespan, are involved in the model. Then the non-dominated sorting genetic algorithm-II (NSGA-II) suitable for solving the problem is designed accordingly. Finally, the numerical analysis shows that the algorithm can obtain satisfactory solution, considering the objective of minimizing maximal heat waiting time is beneficial to avoid the risk of rescheduling, and the research can help decision makers achieve the target of carbon emission reduction ensuring continuous and efficient SCC production.