Patent ID: 6273931
Filing Date: 2001-08-14
Classification: C21B,C21C,Y02P

Abstract:
A method for controlling a smelting reduction process for producing pig iron wherein oxide iron material, coal and oxygen are supplied and an off gas is produced, comprising the steps of:measuring the carbon fraction C in the off-gas in the form of CO and CO.sub.2measuring the hydrogen fraction H.sub.2 in the off-gas in the form of H.sub.2 and H.sub.2 O;determining the C/H.sub.2, ratio in the off-gas;comparing the C/H.sub.2 ratio determined in the off-gas against the C/H.sub.2 ratio prevailing for the coal being supplied, andadjusting the coal supply based on the difference found in the C/H.sub.2 ratios in the off-gas and the coal being supplied such that the fraction of char formed from the coal in a slag layer is kept stable, the fraction being not much less than 20%.