An Efficient Augmented Lagrange Multiplier Method for Steelmaking and Continuous Casting Production Scheduling

Autor: Dan Li, Liuyang Yuan, Nikolaos Rakovitis, Dayong Han, Jie Li, Qiuhua Tang, Zikai Zhang
Rok vydání: 2021
Předmět:
Zdroj: Chemical Engineering Research and Design. 168:169-192
ISSN: 0263-8762
Popis: The steelmaking and continuous casting (SCC) process is one of the vital processes in iron and steel plants since it determines chemical compositions of slabs and is often a bottleneck for iron and steel manufacturing. In this paper, we first develop a discrete-time mixed-integer linear programming (MILP) formulation for a new SCC scheduling problem where different processing routes are used to produce diversified and personalized slab products. To solve the proposed MILP formulation efficiently, we then propose a novel efficient solution algorithm using Augmented Lagrange multiplier method (e-ALM) through relaxation of the coupling constraints and incorporation of penalty components. A heuristic-based list scheduling approach as well as adjacent pairwise swap operations is used to construct a high-quality feasible schedule. A fine-adjusting strategy based on the subgradient direction is proposed to update Lagrangian multipliers dynamically to speed up the convergence. It is shown that the proposed e-ALM is able to generate optimal or near-optimal solutions with 5% optimality for 150 industrial-scale instances and outperform the commercial solver GAMS/CPLEX and the existing Lagrangian relaxation algorithms with better feasible solutions and smaller duality gap within the specified computational time.
Databáze: OpenAIRE