Method and apparatus for producing clean reducing gases from coke oven gas

Abstract

A process and system for producing reducing gases are disclosed, wherein volatile components derived from coal are transformed into reducing gases suitable for utilization as synthesis gas, as a reducing agent for the direct reduction of iron ores and/or as a clean fuel.

1 . A method of treating hot crude coke oven gas from a coke oven to produce a clean reducing gas, comprising 
 partially combusting the hot crude coke oven gas at a temperature greater than about 1000° C. by mixing the hot crude coke oven gas with an oxygen-containing gas to produce a hot reducing gas having a high content of hydrogen and carbon monoxide;    producing high temperature steam by passing the hot reducing gas through a heat exchanger;    utilizing a first portion of the steam to produce electricity; and    utilizing a second portion of the steam in a sulfur removing unit to remove sulfur compounds and other impurities from the reducing gas to produce the clean reducing gas.    
     
     
         2 . The method of  claim 1 , further comprising utilizing at least a portion of the clean reducing gas in a direct reduction plant comprising a direct reduction reactor, a CO 2  removal unit and a gas heater.  
     
     
         3 . The method of  claim 2 , further comprising utilizing a third portion of said steam in the CO 2  removal unit of the direct reduction plant.  
     
     
         4 . The method of  claim 3 , wherein the direct reduction plant is used to directly reduce iron ore.  
     
     
         5 . The method of  claim 2 , wherein a portion of the clean reducing gas is used to heat the coke oven.  
     
     
         6 . The method of  claim 5 , wherein another portion of the clean reducing gas is injected into the direct reduction reactor.  
     
     
         7 . A method of reducing iron oxides in a shaft reduction reactor utilizing coke oven gas, comprising mixing hot crude coke oven gas with an oxygen-containing gas in order to carry out a partial combustion of said coke oven gas to produce a hot reducing gas having a high content of hydrogen and carbon monoxide at a temperature higher than about 1000° C.; passing said hot reducing gas through a heat exchanger in order to produce high temperature steam; utilizing a first portion of said steam in a sulfur removal unit for removing sulfur compounds and other impurities of said reducing gas; and utilizing a second portion of said steam in a CO2 removal unit where exhausted reducing gas is treated to remove carbon dioxide before being recycled into said shaft reduction reactor.