Development and Improvement of the Measuring Methods for the Computer Control of Blast Furnace

Abstract

For the successful control of the hot metal temperature of the blast furnace, it is necessary to measure accurately the operational data such as blast conditions, charge conditions, and top gas compositions which are to be input to the control model. By the use of the mathematical simulation model of the blast furnace, the required accuracies of measurements for the control of the hot metal temperature are investigated. It was found that the measurement accuracies of the N2 content and the CO2 content of the top gas, the Fe content of burden and the blast flow rate were not enough. The followings were carried out in order to improve the accuracies of the calculations of the material and heat balances and the accuracies of the prediction of hot metal temperature.1) Development of the highly accurate gas-chromatography 2) Development of the sinter property tracking system 3) Check of the measurement accuracy of the blast flow rate 4) Improvement of the measurement timing of the hot metal temperatureOwing to these improvements, the automatic computer control system of the hot metal temperature could be applied to Kokura No. 2 BF for 2.5 years until the blow out of the furnace and this system had contributed to the stable and low cost operations.