| 摘要 |
PROBLEM TO BE SOLVED: To provide a flexible and commercial method capable of producing a high calorie gas of the standard 13A and a low calorie gas of the standard 6C, etc., at the same time while arbitrarily producing either of these gas products. SOLUTION: This production method of city gas is to obtain a low temperature-reformed gas comprising methane, carbon dioxide, etc., by steam reforming desulfurized petroleum-based hydrocarbons at a low temperature, treat the low temperature-reformed gas with a membrane device of a two stage circulation type to obtained a gas having high concentration of methane in the impermeable side of its first membrane device and to finally adjust the calorie with LPG to obtain a source gas for a high calorie city gas. A source gas for a city gas having low calorie can be produced at the same time by converting a high temperature-reformed gas obtained by reforming a part of the separated low temperature-reformed gas with a high temperature steam to a converted gas having high hydrogen concentration and finally adjusting the calorie with LPG and diluted air. |
