EAF Energy Optimization at Nucor-Yamato Steel

摘要

Nucor-Yamato Steel (NYS) continuously, works to improve its operations. Energy input optimization has always been at a good level, but there have been obstacles on the way to achieving better results. The most difficult part of the adjustment process is that the control system is divided into several interacting control sub-systems. These subsystems do not take into account the effects of changes made to other sub-systems, and are developed by different vendors in their own knowledge area. As an example, reducing the exhaust gas negative pressure may produce fewer energy losses, but it may cause the furnace to be more prone to cross-arcing and so to damages and loss of uptime. In order to optimize the EAF process as a whole, new SmartFurnace modules were added to the SmartARC system. The SmartARC control system has been in place since 1997 for controlling the electrical energy input at NYS. The new SmartFurnace modules were added in order to implement on-line control of the burner system and the exhaust gas system. This paper describes the EAF system, the main issues in the pursuit of better performance, and a brief description of the new control modules and their added flexibility in coping with the main variations in the other sub-systems. Finally, the new features will be shown, the evolution of some of the adjustments and the results.