Research And Application Of Optimal Control Technology In Converter Gas Recovery Process

It produces a large number of high temperature flue gas with iron oxide dust in convertersteel smelting process, the main component is carbon monoxide that is an industrial fuel withhigher heating value. If without effective recycling and emission control, it will not only pollutethe atmosphere, but also result in energy waste. Converter gas recovery is a production processto recycle CO which is a by-product of the converter production process, it will get recyclableconverter gas after the high temperature flue gas be cooled and purified, it goes without sayingits economic value and social benefits. As a resource and energy intensive industries, iron andsteel industry is big energy eaters, the total industrial energy consumption is about16%of totalenergy consumption, and production and energy consumption costs account for more than24%of the total cost. Therefore, to carry out research of converter gas recovery technology, tofurther improve the gas recovery rate and quality, and to stable production process, this haspractical significance for significantly reducing the level of iron and steel industry energyconsumption, improving resource utilization, and ensuring stable and sustainable development.For domestic steel enterprises converter gas recovery system, as part of the cleaningequipment and control technology is relatively backward, this causes fluctuations of furnaceflue gas pressure, poor stability of the smelting process, and poor of gas recovery and flue gasemission results. In this paper, we use50tons converter of Ma steel’s the second steel rollingplant as the object, for the system’s large inertia, strong coupling, time delay, nonlinear and soon, after further study of OG gas recovery and purification system, I describe the design offurnace pressure control system. On this basis, I make hardware configuration and softwaredevelopment and achieve control operation.The primary goal of converter mouth differential pressure control is to achieve differentialpressure control internal and external of furnace mouth, the purpose is to make converter mouthdifferential pressure by regulating mouth of throat to be micro positive, by this method, it canmake fan ventilation volume and the amount of smoke generated keep consistent, avoidinhalation of smoke spills or air to the furnace, and achieve better effect of gas emissions andgas recovery. In order to realize the computer simulation of control algorithm, this paperdescribes the method and procedure of getting the controlled object model by using impulseresponse method and parameter estimation theory to make system identification, and itintroduces in detail the method to obtain transfer function by using Matlab system identification toolbox’s modeling function, then we use PID neural network and traditional PID controlalgorithm to make simulation for the identified model. On this basis, the paper also proposes anoptimal control scheme to increase the concentration of CO, that using Fuzzy RBF neuralnetwork to online identify mathematical model between furnace pressure and CO concentration,to search for the best settings of differential pressure control loop, and to control the mouthpressure around the setting by tracking control, and this significantly improve the quality of COconcentration and the effect of gas recovery. And this avoids the resurgence of a large numberof CO and the surge of smelting process, stabilizes the steel smelting process, improves the hitrate of blowing, shorts the refining cycle, and achieves increase saving purposes.