Two-stage Heat Balance In The Blast Furnace Heat Control

It will make the blast furnace abnormal if the thermal state is unstable. This will erode the blast furnace faster, shorten its campaign life. It's important to keep the thermal state stable to operate the blast furnace well and prolong its life-span. For this purpose the iron makers have developed many mathematical models to keep the thermal state stable. But these models have many problems due to many reasons. So it is significant to develop a thermal cortrol model which is more dependable.Now the simulation models only consider the blast furnace mechanism , and can't cortrol the blast furnace dynamically. This can't meet the needs of the blast furnace thermal cortrol.And the dynamic models only consider the statistics relations between the input and output variables of the blast furnace neglecting its mechanism. The blast furnace is a heat exchanger and also an oxygen exchanger of the gas and row, there are many physical and chemical changes in it. It is not very reasonable to develop a model only consider the statistics relations.The blast furnace operation is a verycomplicated process, which is effected by many factors such as equipment, operating method and others. To develop a more reliable model must simultaneously consider the mechanism and the statistics relations of the input and output.There is a chemical reserve zone in the stack.In this zone the Fe is present as FeO,and the gas component is close to the balance composition of Fe0.947O/Fe.So there is a part of longitudinal section,in which:l)Gas keeps its component,as ascending.2)The composition of the gas is close to the equilibrium composition of the Fe0 947O+CO-" 0.947Fe+ CO2 under the temperature of the thermal reserve zone of about 1200+100K.If two stage thermal balance and the mass balance model of the blast furnace has been established base on the metallurgy theory. Some formulas to calculate some useful parameters such as coke rate, direct reduce rate have also constructed. This model has two modules: the parameters adjusting module and the forecast module. The parameters adjusting module uses daily mean values to calculate the adjusting coefficient. The forecast module uses the realtime data to calculate the forecastvalues.This thesis based on No.3 blast furnace of the Xiangtan iron and steel company. It match esthe hardware and software of the blast furnace. It was tested with the data of the blast furnace. And it would be applied to other blast furnaces after some modifications.To improve the quality of the model, some methods should be used in future:l.impoving the database and making it have more information.2.considering the mass and thermal accumulation and calculating the effect of the data of every period.