Research On Intelligent Control Strategy Of Hot Blast Stoves Of Steel Plant Based On Expert System

In a steel plant,hot blast stoves are indispensable parts in the production process of ironmaking.This paper is employed to elaborate the study on the hot blast stove control system in No.2 blast furnace in an iron work.However,in this furnace,the control effect of neither the stove changing system nor combustion control system can meet the expected requirements because the systems are controlled manually.The manual control often suffers from tremendous energy consumption and big labor intensity.Therefore,it is imperative to improve the automation level of the hot blast stove.Considering the existing conditions of the hot blast stove in this work,an intelligent control scheme is proposed.The scheme includes the stove changing system and combustion control system.Based on the step pressurizing non-fluctuation stove changing,an intelligent control strategy---changing stove according to the time for supplying air---is proposed to realize non-fluctuation stove changing.The strategy not only well steadilizes air pressure and flow rate,but also prolongs the service life of the hot blast stove,and is helpful for the application of the combustion control system.Considering the detecting condition of the hot blast stove,an combustion control strategy is introduced.The strategy considers the rules and case-based reasoning technique based expert controller.Moreover,the method determines the stage control scheme according to the characteristic of production process in the hot blast stove.Then,combustion intelligent control model is established,and the case-based reasoning technique based expert controller is obtained.The case library is established by summarizing experts' experience.The hot blast stove can adjust the air-fuel ratio and gas flow according to the actual production by using the case retrieving.The method avoids human disturbance and improves the heat of combustion.Furthermore,it deals with the problem of greatly fluctuating of the vault temperature.The proposed intelligent control strategy for the hot blast stove has been evaluated in the plant.The experimental results show that the proposed method has achieved fast control speed and high precision.The method has reached the goal of reducing the labor intensity of operators,saving energy consumption and improving the thermal efficiency.Moreover,the air supply for blast furnace has also achieved the desired effect.