Blast furnace operation method

Abstract

According to a certain viewpoint of the present invention, there is provided a blast furnace operation method comprising blowing a high-concentration hydrogen-containing gas containing 80 mol % or more of hydrogen gas from a tuyere under: a condition in which a blowing temperature of the high-concentration hydrogen-containing gas is room temperature or higher and 300° C. or lower and a gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 200 Nm3/t or more and 500 Nm3/t or less; a condition in which the blowing temperature of the high-concentration hydrogen-containing gas is higher than 300° C. and 600° C. or lower and the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 145 Nm3/t or more; a condition in which the blowing temperature of the high-concentration hydrogen-containing gas is higher than 600° C. and 900° C. or lower and the gas volume of the high-concentration hydrogen-containing gas is 125 Nm3/t or more, or the like.

1 . A blast furnace operation method comprising blowing a high-concentration hydrogen-containing gas containing 80 mol % or more of hydrogen gas from a tuyere under:
 a condition in which a blowing temperature of the high-concentration hydrogen-containing gas is room temperature or higher and 300° C. or lower and a gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 200 Nm 3 /t or more and 500 Nm 3 /t or less;   a condition in which the blowing temperature of the high-concentration hydrogen-containing gas is higher than 300° C. and 600° C. or lower and the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 145 Nm 3 /t or more;   a condition in which the blowing temperature of the high-concentration hydrogen-containing gas is higher than 600° C. and 900° C. or lower and the gas volume of the high-concentration hydrogen-containing gas is 125 Nm 3 /t or more;   a condition in which the blowing temperature of the high-concentration hydrogen-containing gas is higher than 900° C. and 1200° C. or lower and the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 110 Nm 3 /t or more; or   a condition in which the blowing temperature of the high-concentration hydrogen-containing gas is higher than 1200° C. and the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 100 Nm 3 /t or more.   
     
     
         2 . The blast furnace operation method according to  claim 1 ,
 wherein the blowing temperature is higher than room temperature and 300° C. or lower and the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 200 Nm 3 /t or more and 300 Nm 3 /t or less.   
     
     
         3 . The blast furnace operation method according to  claim 1 ,
 wherein the blowing temperature of the high-concentration hydrogen-containing gas is higher than 300° C. and 600° C. or lower and the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 145 Nm 3 /t or more and 600 Nm 3 /t or less.   
     
     
         4 . The blast furnace operation method according to  claim 1 ,
 wherein a flame temperature is 2050° C. or lower.   
     
     
         5 . The blast furnace operation method according to  claim 1 ,
 wherein a flame temperature is higher than 2050° C. and 2150° C. or lower.   
     
     
         6 . The blast furnace operation method according to  claim 1 ,
 wherein a flame temperature is higher than 2150° C. and 2250° C. or lower.   
     
     
         7 . The blast furnace operation method according to  claim 1 ,
 wherein the blowing temperature of the high-concentration hydrogen-containing gas is higher than 600° C. and 1400° C. or lower.   
     
     
         8 . The blast furnace operation method according to  claim 1 ,
 wherein, in a case where the blowing temperature of the high-concentration hydrogen-containing gas is higher than 600° C., the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 1000 Nm 3 /t or less.   
     
     
         9 . The blast furnace operation method according to  claim 1 ,
 wherein, in a case where the blowing temperature of the high-concentration hydrogen-containing gas is higher than 600° C. and the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas is 400 Nm 3 /t or more, a flame temperature is set to 2050° C. or lower.   
     
     
         10 . A blast furnace operation method comprising:
 obtaining a gas volume-carbon consumption parameter correlation, which is a correlation between a gas volume of hydrogen gas in a high-concentration hydrogen-containing gas and a carbon consumption parameter related to a carbon consumption amount when a blowing temperature of the high-concentration hydrogen-containing gas containing 80 mol % or more of the hydrogen gas is a predetermined value, in advance for each flame temperature;   determining the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas at which the carbon consumption amount is reduced compared to that of a current operation, on the basis of the gas volume-carbon consumption parameter correlation; and   blowing the high-concentration hydrogen-containing gas from the tuyere at the determined gas volume.   
     
     
         11 . The blast furnace operation method according to  claim 10 ,
 wherein the gas volume-carbon consumption parameter correlation is obtained for each blowing temperature.   
     
     
         12 . The blast furnace operation method according to  claim 10 ,
 wherein a gas volume-pressure drop change correlation, which is a correlation between the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas and a change amount of a pressure loss with respect to a base operation when the blowing temperature is a predetermined value, is obtained in advance for each flame temperature, and   the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas at which the carbon consumption amount is reduced compared to that of the current operation and the change amount of the pressure loss is a value within a predetermined range is determined on the basis of the gas volume-carbon consumption parameter correlation and the gas volume-pressure drop change correlation.   
     
     
         13 . The blast furnace operation method according to  claim 10 ,
 wherein a gas volume-top gas temperature change amount correlation, which is a correlation between the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas and a change amount of a top gas temperature with respect to a base operation when the blowing temperature is a predetermined value, is obtained in advance for each flame temperature, and   the gas volume of the hydrogen gas in the high-concentration hydrogen-containing gas at which the carbon consumption amount is reduced compared to that of the current operation and the change amount of the top gas temperature is a value within a predetermined range is determined on the basis of the gas volume-carbon consumption parameter correlation and the gas volume-top gas temperature change amount correlation.