Gas separation: apparatus – Apparatus for selective diffusion of gases
Reexamination Certificate
2001-06-25
2003-03-04
Spitzer, Robert H. (Department: 1724)
Gas separation: apparatus
Apparatus for selective diffusion of gases
C095S056000, C096S010000, C096S011000
Reexamination Certificate
active
06527832
ABSTRACT:
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a device for recovering hydrogen generated by decomposition of hydrocarbon gas with steam.
Hydrogen has been used in broad industrial fields as basic raw material in a chemical industry, a fuel for a fuel cell or an atmospheric gas for heat treatment. A representative process to cope with a small demand is decomposition of hydrocarbon gas with steam. A decomposition product contains CO, CO
2
and residual H
2
O other than H
2
. The product cannot be used as such for a fuel cell due to the inclusions; otherwise faculty of the fuel cell would be degraded. In this regard, it is necessary to remove subspecies such as CO, CO
2
and residual H
2
O, before the reformed product is supplied to a fuel cell.
A conventional method of removing subspecies uses a hydrogen-permeating membrane made of such a catalytic element as Pd—Ag or Ta selectively permeable to hydrogen. The hydrogen-permeating membrane has been formed so far as a thin layer on a heat-resistant perforated body, as disclosed in JP 63-294925 A1 and JP 1-164419 A1. Recently, feasibility of a perforated metal body, in which a plurality of holes are formed for passage of hydrogen has been studied instead of a conventional heat-resistant perforated body.
A perforated metal body coated with a hydrogen-permeating membrane is attached to a surface of a hydrogen-recovering device, to which a takeout pipe is coupled, and embedded in a catalyst layer. Hydrogen gas generated by decomposition of hydrocarbon gas with steam selectively passes through the hydrogen-permeating membrane into the hydrogen-recovering device and flows through the takeout pipe to the outside.
A conventional hydrogen-recovering device uses a thick plate as a structural member in order to inhibit thermal deformation caused by heat cycles between high and ordinary temperatures. As a result, the device is heavy, and a special fixing jig is necessarily used for fixing the device in a reforming plant at a predetermined position. The thick plate is processed by etching, machining or electric discharge machining to form holes for passage of hydrogen and a header, and then a hydrogen-permeating membrane such as a Pd—Ag alloy is laser-welded to an external surface of the thick plate. Such processing is troublesome and inappropriate for mass-production at a low cost.
SUMMARY OF THE INVENTION
The present invention aims at provision of a new hydrogen-recovering device, which is light and strong, easy to manufacture by using a thin steel sheet press-worked to a predetermined shape as a structural member.
The present invention proposed a box-shaped or tubular hydrogen-recovering device having a frame made of a ferritic stainless steel.
The box-shaped hydrogen-recovering device has a box-shaped frame made of a ferric stainless steel having a takeout pipe attached to its one side, a plurality of spacers arranged along a lengthwise direction inside said box-shaped frame, perforated metal plates fixed to both surfaces of said box-shaped frame, a hydrogen-permeating membrane clad with a membrane holder fixed to said perforated metal plate, wherein hydrogen gas as a decomposition product of hydrocarbon selectively passes through said hydrogen-permeating membrane and flows to the outside.
The tubular hydrogen-recovering device comprises a pair of upper and lower discs each of which has an opening for passage of hydrogen at its center, a plurality of reinforcement members which extend between said upper and lower discs and locate with the same intervals along a circumferential direction, perforated metal plates which is fixed to a cylindrical surface defined by curved surfaces and end faces of said reinforcement members and is coated with a hydrogen-permeating membrane, and a takeout pipe coupled to one or both of said upper and lower discs, wherein hydrogen passes through said hydrogen-permeating membrane into a cavity inside said perforated plates and flows through said takeout pipe to the outside.
The members other than the hydrogen-permeating membrane are preferable made of a ferritic stainless steel which has a thermal expansion coefficient near that of the hydrogen-permeating membrane.
REFERENCES:
patent: 2824620 (1958-02-01), De Rosset
patent: 3148031 (1964-09-01), Vahldieck et al.
patent: 3203086 (1965-08-01), Eyraud et al.
patent: 3238704 (1966-03-01), Straschil et al.
patent: 3336730 (1967-08-01), McBride et al.
patent: 3447288 (1969-06-01), Juda et al.
patent: 3469372 (1969-09-01), Yamauchi et al.
patent: 5225080 (1993-07-01), Karbachsch et al.
patent: 5259870 (1993-11-01), Edlund
patent: 5453298 (1995-09-01), Gavalas et al.
patent: 5498278 (1996-03-01), Edlund
patent: 5782960 (1998-07-01), Ogawa et al.
patent: 5997594 (1999-12-01), Edlund et al.
patent: 6221117 (2001-04-01), Edlund et al.
patent: 61-278328 (1986-12-01), None
patent: 62102814 (1987-05-01), None
patent: 63-258619 (1988-10-01), None
patent: 63294925 (1988-12-01), None
patent: 01164419 (1989-06-01), None
US 6,340,380, 1/2002, Frost et al. (withdrawn)
Kawatani Kouichi
Oku Manabu
Seki Tsutomu
Utsunomiya Takeshi
Nisshin Steel Co. Ltd.
Spitzer Robert H.
Webb Ziesenhiem Logsdon Orkin & Hanson P.C.
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