GB1132994A - Method of controlling the operation of a blast furnace - Google Patents

Abstract

1,132,994. Controlling blast furnace operation. CENTRE NATIONAL DE RECHERCHES METALLURGIQUES. Dec.6, 1965 [Dec.10, 1964], No.51624/65. Heading C7D. In a method of controlling a blast furnace one or more factors characterizing the operation of the shaft are monitored and any irregularity is corrected without there being any immediate effect on the operation of the lower part of the furnace, while at the same time a factor representative of the thermal condition of the lower part of the furnace is continuously calculated and compared with a previously calculated target value, any difference being caused to initiate corrective action. With regard to the shaft the blast rate, humidity, temperature and oxygen content, the top gas composition, and the quantity of fuel injected, may be examined one to four times per minute and in conjunction with the analysis of the charge used to calculate the characteristic factor which may be one of the following; degree of reduction by hydrogen, degree of reduction by carbon monoxide, degree of reduction by carbon, or degree of utilization of carbon monoxide, defined as the ratio of the actual oxidation state to the equilibrium state at 1000‹C. when all the iron is in the form of FeO. For the lower part of the furnace there is calculated a factor which represents the quantity of heat necessary for the reduction of the amount of silicon desired in the iron produced; variation of this factor from a predetermined value is counteracted by modifying the supply of heat, as by varying the amount of fuel injected, the blast temperature, or its oxygen content.