摘要 |
<p>A method for the gaseous reduction of iron ore to sponge iron in a vertical shaft moving bed reactor (10) wherein a hot gaseous mixture of hydrogen and a carbon monoxide is used to reduce the ore. It has been found unnecessary to use the external catalytic reformer of prior art processes to reform the methane and other hydrocarbon constituents of the natural gas commonly used as a source of gaseous reductants. By establishing a reducing gas recycle loop to which make-up natural gas and steam are fed in the proper proportions, the product sponge iron in the reactor (10) can be used to catalyze hydrocarbon reformation, provided that the carbon content of the recycled gas is maintained low by removing carbon dioxide therefrom. When pure methane is employed, steam/methane molar ratios within the preferred range of 1,4 : 1 to 2.2 : 1 are used.</p> |