Apparatus for converting a feed gas into a product gas

Abstract

Apparatus for converting feed gas (28) into a product gas (29), comprising at least one reactor (1) with a reaction chamber (15) bounded by the inner wall of an outer tube (4) closed at a first outer end and an inner tube (14) received coaxially in this outer tube (4) and provided at both its outer ends with openings, which reactor (1) is provided with an inlet chamber (11) and with an outlet chamber (10), wherein a first wall (31) of the outlet chamber (10) encloses the outer tube (4) and extends therefrom, and a second wall (12) of the outlet chamber (10) lying opposite the first wall (31) encloses the outer tube (4) and extends therefrom, and the inlet chamber (11) is bounded by the second wall (12) of the outlet chamber (10) and a third wall (47) which lies opposite this second wall (12), encloses the outer tube (4) and extends therefrom.

Claims

1. An apparatus for converting a feed gas having components for reaction into a product gas, the apparatus comprising: at least one reactor with a reaction chamber which is provided with an inlet opening for feed gas and an outlet opening for product gas and which is bounded by the inner wall of an outer tube closed at a first outer end and the outer wall of an inner tube received coaxially in this outer tube and provided at both its outer ends with openings, which reactor is provided with an inlet chamber which is in open connection with the at least one inlet opening and with an outlet chamber in which the at least one outlet opening debouches, wherein a first wall of the outlet chamber encloses the outer tube and extends therefrom; a second wall of the outlet chamber lying opposite the first wall encloses the outer tube and extends therefrom, wherein the inlet chamber is bounded by the second wall of the outlet chamber and a third wall which lies opposite this second wall, encloses the outer tube and extends therefrom, wherein the inlet opening is formed in the wall of the outer tube.

2. The apparatus as claimed in claim 1, wherein the outer tube is closed at a second outer end by a releasably coupled cover which is provided with first sealing means for sealing the cover against the outer tube, wherein the inner tube is in open connection with the inlet opening.

3. The apparatus as claimed in claim 2, further comprising a second sealing means for sealing the inner tube against the outer tube in a manner such that the inner tube is in open connection with the inlet opening, and the space bounded by the outer tube and the inner tube is in open connection with the outlet opening.

4. The apparatus as claimed in claim 2, further comprising gaskets of a high temperature-resistant material for securing the cover against a movement of the outer tube in longitudinal direction away from the reaction chamber.

5. The apparatus as claimed in claim 2, further comprising a gas outlet conduit extending through the cover and debouching in the reaction chamber of the at least one reactor.

6. The apparatus as claimed in claim 2, further comprising a third tube extending through the cover for inserting a temperature sensor therein.

7. The apparatus as claimed in claim 2, wherein the reaction includes a catalyst material.

8. The apparatus as claimed in claim 7, wherein the catalyst material is provided on at least a part of a carrier foil enclosed by the outer tube.

9. The apparatus as claimed in claim 8, wherein the carrier foil has in a cross-section through the inner and the outer tube a periodic structure of successive peaks and valleys.

10. The apparatus as claimed in claim 2, wherein the at least one reactor is provided along a part of the inner tube with a heat exchanger for transfer of heat from product gas flowing out of the reactor chamber to feed gas supplied through the inner tube, which heat exchanger is provided by a first heat exchanger element bounded by the inner wall of the inner tube and a second heat exchanger element corresponding to this first heat exchanger element and arranged round the outer wall of the inner tube.

11. The apparatus as claimed in claim 2, wherein a part of the outer tube is provided with a liquid conduit formed round this part and with a third heat exchanger element received in this part for the transfer of heat from product gas flowing out of the reaction chamber to a liquid flowing through this liquid conduit.

12. The apparatus as claimed in claim 9, wherein the respective heat exchanger element is provided by a foil of a heat conductive material, this foil having in a cross-section through the respective tube a periodic structure of successive peaks and valleys.

13. The apparatus as claimed in claim 12, further comprising at least two reactors placed in parallel, wherein the respective inlet chambers are provided by a shared inlet manifold, and the respective outlet chambers are provided by a shared outlet manifold.

14. The apparatus as claimed in claim 13, wherein the number of parallel reactors amounts to 3n.sup.2−3n+1, wherein n is a whole number 2≤n≤13, which reactors in a cross-section are placed adjacently in parallel rows within a regular hexagon, wherein a first outer row comprises n reactors and each subsequent row comprises one reactor more up to a maximum of 2n−1 reactors, after which each subsequent row comprises one reactor less up to a second outer row lying opposite the first outer row, which second outer row comprises n reactors.

15. The apparatus as claimed in claim 14, further comprising a heating means for heating the at least one reaction chamber.

16. The apparatus as claimed in claim 15, wherein the feed gas includes organic compounds and water vapor and the product gas substantially includes carbon dioxide and hydrogen.

Description

(1) The invention will be elucidated hereinbelow on the basis of exemplary embodiments and with reference to the drawings.

(2) In the drawings

(3) FIG. 1 shows a schematic axial section of a reactor for a first embodiment of an apparatus according to the invention,

(4) FIG. 2 shows a schematic axial section of a part of a reactor for a second embodiment of an apparatus according to the invention,

(5) FIGS. 2a, 2b, 2c, 2d are respective cross-sections of the reactor shown in FIG. 2,

(6) FIG. 3 shows a schematic axial section of a part of a reactor for a third embodiment of an apparatus according to the invention,

(7) FIGS. 3a, 3b, 3c, 3d are respective cross-sections of the reactor shown in FIG. 3,

(8) FIG. 4 shows a schematic axial section of a part of a fourth embodiment of an apparatus according to the invention,

(9) FIG. 5 shows a schematic axial section of a part of a fifth embodiment of an apparatus according to the invention,

(10) FIG. 6 is a perspective view of a part of a detail of a reactor of an apparatus as shown in FIG. 1 and FIG. 2,

(11) FIG. 7 is a perspective view of a first embodiment of a folded carrier foil for a catalyst,

(12) FIG. 8 is a perspective view of a second embodiment of a folded carrier foil for a catalyst, and

(13) FIG. 9 is a perspective view of a third embodiment of a folded carrier foil for a catalyst.

(14) Corresponding components are designated in the figures with the same reference numerals.

(15) FIG. 1 shows a reactor 1 for an apparatus (steam reformer) according to the invention in an axial section which intersects two of the inlet openings 13, 26 and outlet openings 27 referred to below. Reactor 1 is formed by an outer tube 4 closed at its top and an inner tube 14 which is received coaxially therein and which is open at its top and provided on its underside with inlet openings 13, wherein the inner wall of outer tube 4 and the outer wall of inner tube 14 bound a reaction chamber 15, the upper part of which is filled with a catalyst on a carrier foil 37. Reactor 1 is provided with an inlet chamber 11 which is in open connection with an inlet opening 26 formed in outer tube 4, and with an outlet chamber 10 into which debouches an outlet opening 27, wherein a first wall 31 of outlet chamber 10 encloses outer tube 4 and extends in transverse direction thereof. A second wall 12 of outlet chamber 10 lying opposite first wall 31 likewise encloses outer tube 4 and extends in transverse direction thereof. Inlet chamber 11 is bounded by second wall 12 of outlet chamber 10 and a third wall 47 which lies opposite this second wall 12 and which likewise encloses outer tube 4 and extends in transverse direction thereof. Outer tube 4 is closed at its second (in the figure lower) outer end by a releasably coupled cover 48 provided on its periphery with gaskets 20, 21 of a high temperature-resistant material, for instance a perfluoroelastomer (Kalrez®), for sealing cover 48 against the inner wall of outer tube 4, wherein the space bounded by outer tube 4 and inner tube 14 is in open connection with outlet opening 27. Inner tube 14 is in open connection with inlet opening 26. Cover 48 is secured by means of a Seeger ring 2 against a movement of outer tube 4 in longitudinal direction away from reaction chamber 15. Inner tube 14 is provided on its inner side with a first heat exchanger element 16 for heating incoming feed gas (represented by arrows 28) and is enveloped on its outer side in the upper part by a catalyst carrier 37, and is provided in the lower part with a second heat exchanger element 17 for cooling outgoing product gas (represented by arrows 29). Extending through cover 48 is a third tube 6 for insertion of a temperature sensor 7 therein. The figure also shows a positive-displacement tube 3 by means of which incoming feed gas 28 is guided through first heat exchanger element 16, and a number of heat-insulating gaskets 5. By releasing Seeger ring 2 the inner tube 14, which is connected fixedly to cover 48, can be pulled with cover 48 out of outer tube 4, wherein the catalyst carrier 37 becomes directly accessible.

(16) FIG. 2 shows a part of a reactor 8 in an axial section which intersects two inlet openings 13, 26 and outlet openings 27. Other than in reactor 1 shown in FIG. 1, a third tube for a temperature sensor extending through the cover is omitted, and positive-displacement tube 3 does not extend as far as cover 48.

(17) FIGS. 2a, 2b, 2c and 2d show cross-sections through reactor 8 along respective broken lines a, b, c, d in FIG. 2.

(18) FIG. 3 shows a part of a reactor 18 in an axial section which intersects two inlet openings 13, 26 and outlet openings 27. Other than in reactor 8 shown in FIG. 2, reactor 18 is provided with a gas outlet conduit 9 extending through cover 48 and debauching in the reaction chamber.

(19) FIGS. 3a, 3b, 3c and 3d show cross-sections through reactor 18 along the respective broken lines a, b, c, d in FIG. 3.

(20) FIG. 4 shows a steam reformer 23 with three reactors 19 connected in parallel in an axial section which intersects two inlet openings 26 and outlet openings 27 of the respective reactors 19. The view of steam reformer 23 is rotated 180° relative to the reactors shown in FIGS. 1, 2, 3. Other than in reactor 1 shown in FIG. 1, a third tube for a temperature sensor extending through the cover is in this example omitted in reactors 19. The respective inlet chambers of the reactors placed in parallel are formed by a shared inlet manifold 111, and the respective outlet chambers are formed by a shared outlet manifold 100.

(21) FIG. 5 shows a steam reformer 24 with three reactors 19 connected in parallel in an axial section which intersects two inlet openings 13, 26 and outlet openings 27 of the respective reactors 19. In steam reformer 24 a part of outer tubes 4 is provided with a liquid conduit formed round this part, in this case a water conduit 25, and with a third heat exchanger element 22 received in this part for the transfer of heat from product gas flowing out of the reaction chamber to water 32 flowing through this water conduit, thus forming steam 33.

(22) FIG. 6 shows a part of an inner tube 14 around which a metal carrier foil 37 with a catalyst layer is arranged, this foil having in a cross-section through the inner tube a periodic structure of successive peaks and valleys.

(23) FIG. 7 shows foil 37 of FIG. 3 in a situation before being arranged round tube 14, wherein peaks 41 and valleys 42 form a rectangular crenellation in a cross-section.

(24) FIG. 8 shows a second embodiment of a foil 37′ in a situation before being arranged round a tube 14, wherein peaks 41′ and valleys 42′ have a regular wave pattern in a cross-section.

(25) FIG. 9 shows a third embodiment of a foil 37″ in a situation before being arranged round a tube 14, wherein peaks 41″ and valleys 42″ form a rectangular crenellation in a cross-section as well as in axial direction.