Method for operating a blast furnace installation

Abstract

A method for operating a blast furnace is presented, said method comprising the steps of collecting a stream of blast furnace gas from the blast furnace; feeding said stream of blast furnace gas and a hydrocarbon containing gas to a reforming plant comprising at least one reformer; reforming said stream of blast furnace gas and said hydrocarbon containing gas in the reforming plant en to produce a stream of syngas; and feeding at least a portion of said stream of syngas to the blast furnace; wherein a stream of h % is added to the hydrocarbon containing gas before step (c) and/or to the stream of blast furnace gas before step (c) and/or to the stream of syngas before step (d) and/or to the tuyere of the blast furnace, wherein the feeding of at least a portion of said stream of syngas to the blast furnace occurs through the shaft of the blast furnace and/or through the tuyere of the blast furnace, and wherein the utilization efficiency of the hydrogen in a blast furnace plant comprising the blast furnace, the reforming plant and a cowper plant is above 60%.

1 . A method for operating a blast furnace, comprising the steps of
 a. collecting a stream of blast furnace gas from a blast furnace having a shaft and at least one tuyere;   b. feeding said stream of blast furnace gas and a hydrocarbon containing gas to a reforming plant comprising at least one reformer;   c. reforming said stream of blast furnace gas and said hydrocarbon containing gas in the reforming plant to produce a stream of syngas; and   d. feeding at least a portion of said stream of syngas to the blast furnace;   
       wherein a stream of is added to the hydrocarbon containing gas before step (c) and/or to the stream of blast furnace gas before step (c) and/or to a mixture comprising the blast furnace gas and the hydrocarbon containing gas before step (c) and/or to the stream of syngas before step (d), and 
       wherein the feeding of at least a portion of said stream of syngas to the blast furnace occurs through the shaft of the blast furnace. 
     
     
         2 . A method for operating a blast furnace, by improving the efficiency of hydrogen utilisation in a blast furnace, the method comprising the combination of H 2  addition to the blast furnace, with a reforming reaction, wherein the part of hydrogen utilization in a blast furnace installation comprising the blast furnace, a reforming plant and a cowper plant is above 60% of the hydrogen fed to the blast furnace, wherein the hydrogen utilization is defined as: (hydrogen input to the blast furnace installation-hydrogen export from the blast furnace installation)/(hydrogen input to the blast furnace installation), wherein the hydrogen fed to the blast furnace is defined as the total hydrogen content of the gas in a cohesive zone of the blast furnace and of the shaft gas injected to the blast furnace at shaft level and the hydrogen fed to the blast furnace is totaling a flow of minimum 200 Nm 3 /t of produced hot metal and out of which a minimum of 50 Nm 3 /t of hot metal are fed to the blast furnace installation in form of molecular hydrogen H 2 , wherein the hydrogen input to the blast furnace includes in particular the hydrogen contained in the syngas, in the injected molecular hydrogen H 2 , in the other hydrogen containing gases, in the injected coal and/or tar, in the humidity of the injected gases and solid fuels and in the humidity of the hot blast. 
     
     
         3 . The method as claimed in  claim 1 , wherein the feeding of at least a portion of said stream of syngas to the blast furnace occurs through the shaft of the blast furnace and through the at least one tuyere of the blast furnace. 
     
     
         4 . The method as claimed in  claim 1 , wherein at least a part of the hydrogen fed to the blast furnace installation is injected through the tuyere of the blast furnace. 
     
     
         5 . The method according to  claim 1 , wherein the feeding of at least a portion of said stream of syngas to the blast furnace occurs through the shaft of the blast furnace and through the tuyere of the blast furnace. 
     
     
         6 . The method according to  claim 1 , wherein the stream of H 2  is added to the stream of syngas with a temperature below 600° C. 
     
     
         7 . The method according to  claim 1 , wherein the stream of blast furnace gas and/or the stream of hydrocarbon containing gas is hydrogenated and/or desulphurised in a hydrogenation and desulphurization unit upstream of the reforming plant. 
     
     
         8 . The method according to  claim 7 , wherein at least part of the hydrogen is added to the stream of hydrocarbon containing gas upstream of the hydrogenation and desulphurization unit. 
     
     
         9 . The method as claimed in  claim 1 , wherein the stream of H 2  is produced by electrolysis in an electrolysis cell. 
     
     
         10 . The method as claimed in  claim 9 , wherein an electric power for operating the electrolysis cell is produced by a renewable source. 
     
     
         11 . The method as claimed in  claim 1 , wherein the hydrocarbon containing gas comprises natural gas, coke oven gas and/or biogas. 
     
     
         12 . The method as claimed in  claim 1 , wherein the at least one reformer of the reforming plant is a regenerative reformer. 
     
     
         13 . The method as claimed in  claim 1 , wherein the at least one reformer of the reforming plant is a catalytic dry and/or wet reformer of any type, in particular bottom fired, side fired, terrace type or top fired. 
     
     
         14 . The method as claimed in  claim 1 , wherein the reforming plant comprises two reformers, in particular a pre-reformer and a main reformer. 
     
     
         15 . The method as claimed in  claim 1 , wherein the reforming at step (c) is performed non-catalytically. 
     
     
         16 . The method as claimed in  claim 1 , wherein the reforming at step (c) is combined with a partial oxidation of hydrocarbons. 
     
     
         17 . The method as claimed in  claim 1 , wherein a reduction potential of the syngas ( 26 ,  28 ) produced at step (c) is higher than 6, wherein the reduction potential is defined by the molar ratio (cCO+cH 2 )/(cH 2 O+cCO 2 ). 
     
     
         18 . The method as claimed in  claim 1 , wherein the reforming at step (c) is performed at a temperature above about 900° C. 
     
     
         19 . The method as claimed in  claim 1 , wherein the stream of blast furnace gas is further subjected to a gas cooling and/or cleaning and/or pressurization step, a vapor removal step, a dust removal step, metals removal step, HCl removal step and/or sulfurous component removal step, before being fed to the reformer. 
     
     
         20 . The method as claimed in  claim 1 , wherein a stream of steam is added to the hydrocarbon containing gas and/or a stream of steam is added to the blast furnace gas after the cleaning step. 
     
     
         21 . The methods as claimed in  claim 1 , wherein a stream of blast furnace gas is used in the burners of the reforming plant. 
     
     
         22 . A blast furnace installation comprising a blast furnace provided with a shaft, tuyeres arranged for feeding a first stream of a hydrogen containing gas to the blast furnace and gas inlets in the shaft of the blast furnace arranged for feeding a stream of syngas to the blast furnace, said blast furnace installation further comprising:
 a reforming plant comprising at least one reformer in fluidic connection with the top of the blast furnace and with a source of a hydrocarbon containing gas, said reformer being arranged for converting a stream of blast furnace gas and the hydrocarbon containing gas to a stream of syngas and being in fluidic downstream connection with said gas inlets in the shaft of the blast furnace; and   a source of a stream of H 2  in fluidic connection with the at least one reformer and/or with the gas inlets in the shaft and/or the tuyere of the blast furnace.   
     
     
         23 . The blast furnace installation as claimed in  claim 22 , wherein the blast furnace installation is configured for implementing a method for operating a blast furnace comprising
 a. collecting a stream of blast furnace gas from a blast furnace having a shaft and at least one tuyere;   b. feeding said stream of blast furnace gas and a hydrocarbon containing gas to a reforming plant comprising at least one reformer;   c. reforming said stream of blast furnace gas and said hydrocarbon containing gas in the reforming plant to produce a stream of syngas; and   d. feeding at least a portion of said stream of syngas to the blast furnace:   
       wherein a stream of H 2  is added to the hydrocarbon containing gas before step (c) and/or to the stream of blast furnace gas before step (c) and/or to a mixture comprising the blast furnace gas and the hydrocarbon containing gas before step (c) and/or to the stream of syngas before step (d), and 
       wherein the feeding of at least a portion of said stream of syngas to the blast furnace occurs through the shaft of the blast furnace. 
     
     
         24 . The blast furnace installation as claimed in  claim 22 , wherein the reformer is in fluidic downstream connection with the tuyeres of the blast furnace and with the gas inlets in the shaft of the blast furnace. 
     
     
         25 . The blast furnace installation as claimed in  claim 22 , wherein the reforming plant comprises a regenerative reformer. 
     
     
         26 . The blast furnace installation as claimed in  claim 22 , wherein the reforming plant comprises a catalytic dry and/or wet reformer, and/or wherein the reforming plant comprises two reformers, in particular a pre-reformer and a main reformer. 
     
     
         27 . The blast furnace installation as claimed in  claim 22 , wherein the reforming plant further comprises a partial oxidation reactor. 
     
     
         28 . The blast furnace installation as claimed in  claim 22 , wherein the fluidic connection with the top of the blast furnace arranged for conveying a stream of blast furnace gas to the reforming plant further comprises a gas cooling and/or cleaning and/or pressurizing plant, a vapor removal unit, a dust removal unit, metals removal unit, HCl removal unit and/or sulphurous component removal unit. 
     
     
         29 . The blast furnace installation as claimed in  claim 22 , wherein the fluidic connection with the top of the blast furnace arranged for conveying a stream of blast furnace gas to the reforming plant further comprises a pressuring unit and/or a hydrogenation and desulphurization unit.