The Design And Implementation Of Combustion Control System For Regenerative Walking-beam Furnace

There is a regenerative walking-beam furnace with air regenerator in steel rolling workshop of Ningxia Henli Iron and Steel Limited. Slabs are charged on side of furnace and discharged on other side, the largest heating capacity is 120 t/h. Because the control of the furnace such as combustion process, temperature and pressure control are manual adjustments, it is very difficult to achieve accurate temperature control for each zone of furnace. Energy consumption is high, quality of heating billet is poor. In order to meet market demand, the company rebuilt the production line into a bar rods and wire composite production lines. As high-speed wire rod production of 82B need the higher quality of heating billet, the original control mode can not meet the needs of high-speed wire of 82B. The furnace control system has been technological transformed.The existing problems and the need to achieve the goal of the furnace are expatiated in this paper. The relationship of heat value of gas, gas and oxygen content of air-fuel ratio, the gas flow and temperature are analysed. In the energy emission reduction and enhance the quality of steel billet heating purposes, according to the new use of gas. Focus of the furnace combustion control strategies, using fuzzy PID control strategies, improved cross-limiting dual-control strategy and expert control strategy, gas, air flow and furnace pressure to regulate. Detailed analysis of the gas and air the two-loop limiter set and control the process, ensure that air and gas in the mutual relations with the same time, accelerate the pace of adjustment of the system so that the furnace at its best state of combustion. According to the furnace of the production process parameters that the reliable operation of the system, design selection reasonable, PLC system configuration flexibility, the program can be convenient on-line conditioning, temperature control to meet heating requirements of 82B billet.The implementation methods of the furnace combustion process optimization model are also discussed in the industry. Intelligent optimization combustion system used mainly VC++languages modular design process, using OPC technology applications and software configuration of communication. Debugging operation and simulation results show that the combustion optimization model effectively improve the stability of the temperature, Prepared by the burning gas heat value to the impact, for optimal control of the burning furnace to provide an effective way.