| 摘要 |
PROBLEM TO BE SOLVED: To remove impurities such as carbon dioxide, moisture, oil components and hydrocarbons other than methane from a fuel gas so as to increase purity of fuel gas constituents such as hydrogen, carbon monoxide and methane, provided that the fuel gas is obtained through anaerobic fermentation or thermal decomposition of an organic matter.SOLUTION: In a method for purifying the fuel gas obtained through anaerobic fermentation or thermal decomposition of the organic matter, an impurity treatment step is carried out, wherein the impurities in a crude fuel gas BG1 is condensed using cold energy of a liquefied natural gas NG1 and removed as solids or liquid from the crude fuel gas BG1. In the method, a purified fuel gas BG2 from which the impurities are removed is separated and recovered, and a natural gas NG2 that vaporizes through heat exchange with the impurities is recovered. |
