Patent ID: 7517507

Claim:
A steam reformer comprising a double-cylinder structure having an inner cylinder and an outer cylinder surrounding the inner cylinder; the inner cylinder containing a high-temperature reaction section and an adjacent section being adjacent to the high-temperature reaction section; the high-temperature reaction section containing a mixed-catalyst bed prepared by mixing a steam reforming catalyst and an oxidation catalyst, and having an oxygen-containing gas introduction section; and the outer cylinder containing a steam reforming catalyst bed, thereby forming the steam reformer of double-cylinder structure; wherein a heat transfer suppresser is structured in the steam reformer to suppress heat transfer from the high-temperature reaction section to the adjacent section or to the oxygen-containing gas introduction section, whereby a vacant layer isolating the high-temperature reaction section from the adjacent section at a specific distance is formed, the vacant layer structuring the heat-transfer suppressor to suppress heat transfer between the high-temperature reaction section and the adjacent section, the steam reformer further comprising, within the gas introduction section, an introduction conduit extending along the axis of inner cylinder, and an ejection part proximal the front end of the introduction conduit, introduction conduit having an outward support piece protruding outward from it and a support piece protruding inwardly within the inner cylinder opposite the outward support piece, whereby the bottom of a mixed catalyst bed is supported by an air-permeable support positioned on support pieces, whereby the vacant layer between the support and the adjacent section 7 is formed.