Optimization of iron and steel manufacturing plant considering electricity price tariff and electric arc furnace control

Abstract

The iron and steel industry, which is a highly energy-intensive sector, seeks to increase energy efficiency and reduce operating costs by optimizing the distributions of byproduct gases, steam, and electricity throughout the production process. The operating costs of an iron and steel plant typically include the purchase cost of liquefied natural gas fuel, electricity, and penalties for byproduct gas holders. Electricity tariffs have a significant impact on energy costs through two factors: the energy charge, which is related to energy consumption varying with time, and the demand charge, which is proportional to the peak power. In this study, the characteristics of electricity tariffs and multi-energy systems, specifically for iron and steel plants, are considered. In the proposed method, electric arc furnaces are employed as controllable units to flexibly manage the power load. The optimization model utilized in the plant adopts a mixed-integer linear programming approach to minimize the overall operating costs. Several case studies were conducted to verify the effectiveness of the proposed methods, and the total costs associated with different cases were compared.