Selection and Linearization of Blast Furnace Steady State Model

In order to develop steady state models of blast furnase systematically, the auther proposed “Basic Model of Blast Furnace operation (BM-BF)” in his Paper (1). According to this BM-BF, the equation of relation between reaction raw materials and reaction products (I/O-BE: Input/Output-Basic Equation) could be casily derived by making use of material balance and reaction products analysis data. And the equation of relation between reaction rate, reaction products and reaction raw materials (N-BE: Node-Basic equation) could be also obtained at each node of BM-BF. In his next Paper (2), the auther proposed “Basic Model of Simplified Blast Furnace (BM-SBF)” in order to avoid mathematical complexity resulting from many I/O variables of real blast furnace. He showed that the equations to be solved outnumbered the unknowm variables to be obtained when calculation was made to get reaction products by I/O-BE. Therefore, he indicated that the various combination of solution could be obtained depending on how to select the equations. In the first part of this Paper, based on two Goodness Criteria (rmsD, rmsN), the various calculating methods of reaction products mentioned above were compared each other by adopting the process data (raw materials and reaction product analysis data) generated randomly. In order to apply two Goodness Criteria quantitatively, it was necessary that the calculating methods of reaction products should be linearized with the process data. Attempts were made to linearize the calculating methods and he found the way of linearization with quite good accuracy. The methods of linearization and its results were also described, in the second part of this paper. Finally, the auther indicated that the calculating method employed traditionally could be derived from two Goodness Criteria proposed here.