Energy System Optimization for a Scrap Based Steel Plant Using Mixed Integer Linear Programming

Abstract

In this work a mathematic model to simulate and optimize the energy system of a scrap based plant has been developed. Scrap based steelmaking is an energy intense production system. The potential for energy saving by system optimization is therefore high, even if the percentage of saved energy is relatively small. The model includes scrap pre-treatment, electrical arc furnace, ladle furnace and continuous casting units. To estimate the chemical compositions of the scrap charged into the EAF a statistical model based on an existing EAF plant has been used to provide the inputs to the model. Distribution factors have been used to describe the distribution of elements and oxides between the steel, slag and off gas/dust. To calculate the energy consumption in the electrical arc furnace a combination of an empirical and theoretical energy formula has been used. The model represents a general description of the most common process in electric steelmaking. It is suited to be adapted for specific plants with adjustments to the model parameters. The model gives reasonable results which follow the chemical composition of steel and slag and yield. The model can be a powerful tool to optimize the scrap mix and injectants towards energy and costs.

Systematic Optimization Using Mathematical Model of Electrical Arc Furnace Producing Liquid Steel

“…e purpose of this research is to develop a mathematical model based on composition-level material ow and an empirical formula of electrical energy for EAF to simulate and minimize energy usage. A previous study on this topic had only the goal of minimizing energy use (Riesbeck et al, 2011); the present study also considers minimization of CO 2 emission. Calculation of CO 2 emission refers to the 2006 IPCC guideline for national greenhouse gas inventory (OECD/IEA, 2007).…”