Abstract
Novel coal gasification in supercritical water concept has been studied and experimentally demonstrated. Hydrocarbon including coal is partially oxidized using oxygen under supercritical water condition (above 374℃ and 22MPa) to generate a gas composed of H_2,CO_2,CH_4 and CO. Hydrogen and carbon dioxide are main constituents. Impurities sulfur and nitrogen are transformed into H_2S and N_2 with small amount of NH_3 that is easily separated from the gas. Carbonyl sulfide (COS) is scarcely generated, so that gas purification is simplified. The preliminary evaluation of supercritical water gasification system shows a possibility of CO_2 separation in the form of Liquid. These results indicate supercritical water gasification is one of promising technologies in future environmental aspects.
