Optimization of high energy intensity systems, case study: Electric arc furnace

Document Type : Original Article

Authors

1 School of Mechanical Engineering, Shiraz University, Shiraz, Iran

2 Department of Renewable Energies and Environment, Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran

3 Department of Control Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran

10.22109/jemt.2022.282062.1295

Abstract

The paper establishes a framework for finding the optimal inputs into complex systems with higher energy intensity. It has a lower computational load, higher reliability, and better accuracy. The first is carried out through the developed linearization algorithm of a system. There is the ability to match every output to input to reach reliability, and a sophisticated algorithm guarantees accuracy. An Electric Arc Furnace model is chosen to validate the framework because of its nonlinear functions, complexity, and significant energy intensity. The procedure is applied to an EAF model. At the step’s end, liquid mass, liquid temperature, and liquid grade must reach the desired ranges. The step is to be accomplished at the lowest cost in a determined time. The technique linearizes the nonlinear model around an operating point in the first step and reduces the system’s order. A suitable pairing is offered based on minimum interaction and passing some necessary decentralized integral controllable requirements in the second step. The third step is based on discretizing the operating point’s linearized system. This algorithm is iterated around new operating points. A comparison between the nonlinear system and reduced linear systems with the same feeds will be made in any iteration. If the results are compatible with each other, the next optimum feeds are estimated. Otherwise, the sample time decreases, and the loop should be repeated for the previous point. The study is performed on a well-known EAF model with 14 state variables and seven input variables. The model’s outcome also is.

Keywords

Main Subjects


1. Association WS. World steel in figures 2012. World Steel Assoc 2012.
2. Gruenspecht H. International energy outlook 2011. Cent Strateg Int Stud 2010.
3. Taylor P. Energy Technology Perspectives 2010. Scenar Strateg To 2010;2050.
4. Bisio G, Rubatto G, Martini R. Heat transfer, energy saving and pollution control in UHP electric-arc furnaces. Energy 2000;25:1047–66.
5. Association WS. Energy use in the steel industry. World Steel Association; 2014.
6. Fruehan RJ, Fortini O, Paxton HW, Brindle R. Theoretical minimum energies to produce steel for selected conditions. Carnegie Mellon University, Pittsburgh, PA (US); Energetics, Inc., Columbia . . . ; 2000.
7. Association WS. Fact sheet: energy use in the steel industry. Worldsteel Comm Econ Stud Brussels, Brussels 2016.
8. Association WS. World steel in figures 2014. World Steel Assoc 2014.
9. A Handbook of World Steel Statistics. 1978.
10. Association WS. Annual steel production 1980-2013 2014.
11. Wakelin DH, Fruehan RJ. The making, shaping and treating of steel Iron Making. David H Wakelin, Richard J Fruehan//Latest Technol 1999;2:497–533.
12. Toulouevski YN, Zinurov IY. Innovation in electric arc furnaces. Nov Iorque Springer 2010:1–23.
13. J.A.T. Jones. Electric Arc Furnace Steelmaking 2005.
14. Diancai G, Irons A. Modeling of radiation intensity in an EAF. third Int. Conf. CFD Miner. Process Ind. CSIRO, Melbourne, Aust., 2003.
15. MacRosty RDM, Swartz CLE. Dynamic optimization of electric arc furnace operation. AIChE J 2007;53:640–53.
16. MacRosty RDM, Swartz CLE. Dynamic modeling of an industrial electric arc furnace. Ind Eng Chem Res 2005;44:8067–83.
17. Bekker JG, Craig IK, Pistorius PC. Model predictive control of an electric arc furnace off-gas process. Control Eng Pract 2000;8:445–55.
18. Oosthuizen DJ, Craig IK, Pistorius PC. Economic evaluation and design of an electric arc furnace controller based on economic objectives. Control Eng Pract 2004;12:253–65.
19. Saboohi Y, Fathi A, Škrjanc I, Logar V. Optimization of the electric arc furnace process. IEEE Trans Ind Electron 2018;66:8030–9.
20. Coetzee LC, Craig IK, Rathaba LP. MPC control of the refining stage of an electric arc furnace. IFAC Proc Vol 2005;38:151–6.
21. Skogestad S, Morari M. Variable selection for decentralized control 1992.
22. Khaki-Sedigh A, Moaveni B. Control configuration selection for multi variable plants. vol. 391. Springer; 2009.
23. Haggblom KE. Integral controllability and integrity for uncertain systems. 2008 Am. Control Conf., IEEE; 2008, p. 5192–7.
24. Skogestad S, Postlethwaite I. Multivariable feedback control: analysis and design. vol. 2. Citeseer; 2007.
25. Bekker JG, Craig IK, Pistorius PC. Modeling and simulation of an electric arc furnace process. ISIJ Int 1999;39:23–32