Process utilizing synthesis gas for improving the environmental impact of the reduction of iron ore in blast furnaces

Abstract

A BF iron-ore reduction process for the production of iron and/or iron-carbon compounds with low environmental impact is described, in which a synthesis gas produced from a hydrocarbon stream with a short contact time-catalytic partial oxidation (SCT-CPO) process integrated with the iron-ore reduction process is also used in the BF.

1 - 10 . (canceled) 
     
     
         11 . A method for reduction of iron ores in a blast furnace for production of iron and/or iron-carbon compounds, the method comprising:
 combustion of coke, wherein synthesis gas produced by a hydrocarbon stream with a short contact time-catalytic partial oxidation process (SCT-CPO) integrated with the method is also introduced into the blast furnace.   
     
     
         12 . The method of  claim 11 , wherein the coke is produced in a coke oven upstream of the blast furnace, and wherein the SCT-CPO process produces synthesis gas using a gaseous hydrocarbon stream and an oxidizing agent selected from among oxygen, enriched air, air, and combinations thereof. 
     
     
         13 . The method of  claim 12 , wherein the SCT-CPO process produces synthesis gas further using steam. 
     
     
         14 . The method of  claim 12 , wherein the gaseous hydrocarbon stream comprises one or more gases selected from among natural gas, gases deriving from chemical processes, refinery gases, and gases produced by the fermentation of biomass. 
     
     
         15 . The method of  claim 11 , wherein the hydrocarbon stream comprises blast furnace gas recycled from the blast furnace and coke oven gas recycled from the coke oven, thereby carrying out partial recycling of carbon atoms. 
     
     
         16 . The method of  claim 11 , wherein the coke oven gas undergoes a desulphurization treatment before being used in the SCT-CPO process. 
     
     
         17 . The method of  claim 11 , wherein the oxidizing agent fed to the SCT-CPO process comprises oxygen produced by a process of electrolysis of water in liquid or steam form. 
     
     
         18 . The method of  claim 11 , wherein hydrogen produced by a process of electrolysis of water in liquid or steam form is added to the synthesis gas produced by the SCT-CPO process. 
     
     
         19 . The method of  claim 11 , wherein the SCT-CPO process is carried out under the following operating conditions:
 a. pressure higher than an operating pressure of the blast furnace, preferably between 2 and 15 bar g , more preferably between 2.5 and 10 bar g , even more preferably between 3 and 8 bar g ;   b. temperature of reagent mixtures comprised between 100 and 600° C., preferably between 250 and 450° C.;   c. O 2 /C ratio (v/v) expressed as moles of oxidant O 2 /moles of carbon C in the reagent mixture comprised between 0.30 and 0.70 v/v, preferably between 0.50 and 0.65 v/v;   d. S/C ratio expressed as moles of steam/moles of carbon C in the reagent mixture between 0 and 1.5 v/v, preferably between 0 and 0.5 v/v.   
     
     
         20 . The method of  claim 19 , wherein the SCT-CPO process is carried out under a pressure between 2 and 15 bar g . 
     
     
         21 . The method of  claim 20 , wherein the SCT-CPO process is carried out under a pressure between 2.5 and 10 bar g . 
     
     
         22 . The method of  claim 21 , wherein the SCT-CPO process is carried out under a pressure, even more preferably between 3 and 8 bar g . 
     
     
         23 . The method of  claim 19 , wherein the temperature of the reagent mixtures is comprised between 250 and 450° C. 
     
     
         24 . The method of  claim 19 , wherein the O 2 /C ratio (v/v) is expressed as moles of oxidant O 2 /moles of carbon C in the reagent mixture comprised between 0.50 and 0.65 v/v. 
     
     
         25 . The method of  claim 19 , wherein the S/C ratio is expressed as moles of steam/moles of carbon C in the reagent mixture between 0 and 0.5 v/v. 
     
     
         26 . The method of  claim 11 , wherein the SCT-CPO process is carried out with a percentage by volume of blast furnace gas in the hydrocarbon stream comprised between 0 and 60%. 
     
     
         27 . The method of  claim 26 , wherein the SCT-CPO process is carried out with a percentage by volume of blast furnace gas in the hydrocarbon stream comprised between 15 and 50%. 
     
     
         28 . The method of  claim 11 , wherein the SCT-CPO process is carried out with a percentage by volume of coke oven gas in the hydrocarbon stream comprised between 0 and 60%. 
     
     
         29 . The method of  claim 11 , wherein the SCT-CPO process is carried out with a percentage by volume of coke oven gas in the hydrocarbon stream comprised between 15 and 50%.