| 摘要 |
PROBLEM TO BE SOLVED: To provide a methane concentration apparatus and a methane concentration method which exhibits high treating efficiency and can be used for recovering a gas having high methane concentration in high methane yield. SOLUTION: The first separation membrane 16 and the second separation membrane 28 have high heat-resistance compared with membranes made of organic materials and therefore are resistant to the expansion of pore diameter and the breakage of the membrane even by applying a high pressure, because these membranes are made of inorganic porous materials. Accordingly, the raw material gas can be supplied at a high pressure, to thereby attain a sufficiently high separation membrane characteristics, that is, a carbon dioxide/methane permeability coefficient ratio of≥5 and a carbon dioxide permeability of≥1×10<SP>-9</SP>(mol×m<SP>-2</SP>×s<SP>-1</SP>×Pa<SP>-1</SP>), and thus a gas having high methane concentration can be recovered at a high treatment efficiency in high methane yield. COPYRIGHT: (C)2009,JPO&INPIT |
