EP0194067A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Steam reforming hydrocarbons
Assignee: Imperial Chemical Industries Ltd
•
Filing: 1986-02-18
•
Granted: —
•
Expires: 2006-02-18
Abstract
Abstract Hydrocarbon steam reforming process and apparatus wherein blind ended, ie double pass, externally heated reformer tubes (52) are employed. The inner, ie return, tubes (80) are insulated so that there is only a small temperature drop between the reacted gas leaving the catalyst zone (90) and entering the return tubes (80) and the gas leaving the return tubes (80). <??>The outer, blind-end, tubes (52) preferably have fins (54) and are surrounded by sheaths (56) through which the heating medium passes. The heating medium is preferably hot gas obtained by subjecting the primary reformed gas to secondary reforming.
Inventors
- 👤 Sidney Percy Smith Andrew
- 👤 Ralph Jones Doy
- 👤 Antony Peter John Limbach
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 17:58
CPC Classifications
C; C01; C01B; C01B3/00; C01B3/02; C01B3/32; C01B3/34; C01B3/38; C01B3/382; B; B01; B01J; B01J19/00; B01J19/24; B01J19/2415; B01J19/2425; B01J8/00; B01J8/02; B01J8/06; B01J8/062; C01B3/384; B01J2208/00; B01J2208/00008; B01J2208/00017; B01J2208/00106; B01J2208/00115; B01J2208/00132; B01J2208/00168; B01J2208/00176; B01J2208/00477; B01J2208/00495; B01J2208/0053; C01B2203/00; C01B2203/08; C01B2203/0805; C01B2203/0811; C01B2203/0816; C01B2203/0838; C01B2203/0844; C01B2203/14; C01B2203/142; C01B2203/143; C01B2203/80; C01B2203/82
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
123 words
A process for producing a product gas stream containing hydrogen and carbon oxides by incomplete catalytic reaction of a hydrocarbon feedstock with steam and/or carbon dioxide by passing a reactants stream containing said feedstock and said steam and/or carbon dioxide over a catalyst disposed in an elonated, externally heated, zone and withdrawing the product gas stream through a tube within that zone and countercurrently to the flow of said reactants stream over the catalyst; and is characterised by limiting heat exchange between the product gas stream and the reactants .stream across the wall of the tube so that the temperature of the product gas stream leaving the tube is less than that of such stream leaving the elongated zone by at most 100°C.
Claim 2
Dependent Claim
123 words
A process for producing a product gas stream containing hydrogen and carbon oxides by incomplete catalytic reaction of a hydrocarbon feedstock with steam and/or carbon dioxide by passing a reactants stream containing said feedstock and said steam and/or carbon dioxide over a catalyst disposed in an elonated, externally heated, zone and withdrawing the product gas stream through a tube within that zone and countercurrently to the flow of said reactants stream over the catalyst; and is characterised by limiting heat exchange between the product gas stream and the reactants .stream across the wall of the tube so that the temperature of the product gas stream leaving the tube is less than that of such stream leaving the elongated zone by at most 100°C.
Claim 3
Dependent Claim
24 words
A process according to claim 1 wherein the product gas stream cools by less than 30 0 C during its passage along the tube.
Claim 4
Dependent Claim
53 words
A process according to claim 1 or claim 2 wherein the product gas stream is reacted with a gas containing free oxygen in an adiabatic catalyst zone whereby to effect reaction of further hydrocarbon to carbon oxides and hydrogen and the resultant hot gas stream is used to externally heat the elongated zone.
Claim 5
Dependent Claim
49 words
A process according to claim 3 wherein the reaction of the product gas is effected in a secondary reformer and the product gas stream is fed from the outlet of the elongated zone, via the tube, to the secondary reformer with a temperature fall of no more than 50°C.
Claim 6
Dependent Claim
41 words
A process according to claim 3 or claim 4 wherein, prior to feeding the reactants to the elongated zone, they are heated by heat exchange with the hot gas stream after the latter has been used for heating the elongated zone.
Claim 7
Dependent Claim
49 words
A process according to any one of claims 3 to 5 wherein, while in heat exchange with the elongated zone, the hot gas stream only contacts surfaces made of one or more metals having substantially no catalytic activity, whether in metallic or oxide form, for reactions of carbon monoxide.
Claim 8
Dependent Claim
57 words
A process according to any one of claims 1 to 6 wherein said elongated zone is heated by passing a stream of the heating medium, in a direction counter-current to the flow of reactants through the elongated zone, through a sheath surrounding the elongated zone and extending for at least a major part of the length thereof.
Claim 9
Dependent Claim
19 words
A process according to claim 7 wherein the outlet end region of the elongated zone extends beyond the sheath.
Claim 10
Dependent Claim
33 words
A process according to any one of claims 1 to 8 wherein the outer wall of the elongated zone has, for at least the major part of the length thereof, an extended surface.
Claim 11
Dependent Claim
21 words
A process according to claim 9 wherein the extended surface of the elongated zone terminates short of the outlet end thereof.
Claim 12
Dependent Claim
128 words
Apparatus for conducting an endothermic catalytic reaction comprising (a) a tubular reactor having (i) a first tube, blind at one end, provided with an inlet at the other end, (ii) a second tube disposed within, and extending along, the first tube, thereby providing a space between the first and second tubes for receipt of a catalyst, the interior of said second tube communicating with the space between said first and second tubes at the blind end of said first tube, and said second tube having an outlet at the inlet end of said first tube, and (b) means for supplying a heating fluid to the external surface of the first tube, characterised in that the second tube carries internally, or externally, or both, a layer of thermal insulation.
Claim 13
Dependent Claim
128 words
Apparatus for conducting an endothermic catalytic reaction comprising (a) a tubular reactor having (i) a first tube, blind at one end, provided with an inlet at the other end, (ii) a second tube disposed within, and extending along, the first tube, thereby providing a space between the first and second tubes for receipt of a catalyst, the interior of said second tube communicating with the space between said first and second tubes at the blind end of said first tube, and said second tube having an outlet at the inlet end of said first tube, and (b) means for supplying a heating fluid to the external surface of the first tube, characterised in that the second tube carries internally, or externally, or both, a layer of thermal insulation.
Claim 14
Dependent Claim
50 words
Apparatus according to claim 11 wherein the thermal insulation is associated with the second tube for at least that portion of the second tube that occupies the region extending from 10% to 30% of the length of the first tube, as measured from the inlet end of said first tube.
Claim 15
Dependent Claim
47 words
Apparatus according to claim 11 or claim 12 wherein the insulation is provided by a sleeve enclosing a gas space, or a space filled with fibrous insulation, with one end of the sleeve fastened to the second tube and the other end free to expand or contract.
Claim 16
Dependent Claim
82 words
Apparatus according to claim 12 wherein the second tube comprises welded together tube sections and at least two adjacent sections each have a sleeve enclosing a gas space, or a space filled with fibrous insulation, with one end of each sleeve fastened to its associated section and the other end free to expand or contract, the free end of the sleeve of one of said adjacent sections being adjacent the fastened end of the sleeve on the section adjacent that one section.
Claim 17
Dependent Claim
23 words
Apparatus according to claim 13 or claim 14 wherein the fastened end of the, or each, sleeve is upstream of the free end.
Claim 18
Dependent Claim
20 words
Apparatus according to any one of claims 13 to 15 wherein the sleeve or sleeves are inside the second tube.
Claim 19
Dependent Claim
62 words
Apparatus according to any one of claims 11 to 16 wherein a sheath is provided surrounding the first tube and extending for at least the'major part of the length thereof thereby providing a space between the sheath and the first tube having a cross-sectional area between 0.1 and 1.0 times the cross-sectional area of the space between the first and second tubes.
Claim 20
Dependent Claim
34 words
Apparatus according to claim 17 wherein the sheath terminates short of the blind end of the first tube, leaving 10 to 30% of the length of the first tube unsheathed at the blind end.
Claim 21
Dependent Claim
69 words
Apparatus according to any one of claims 11 to 18 wherein the first tube has, for at least a major part of its length, an extended outer surface such that, over that portion having the extended outer surface, the external surface area is 1.5 to 10 times the area of the curved surface of a cylinder of radius equal to the minimum cross-sectional radius of the extended outer surface.
Claim 22
Dependent Claim
73 words
Apparatus according to claim 19 wherein the portion of the outer surface of the first tube having the extended surface terminates short of the blind end of the first tube and the outer surface of the first tube is cylindrical over the portion from the end of the extended surface portion to the blind end, said portion having a cylindrical outer surface constituting 4 to 20X of the length of the first tube.
Claim 23
Dependent Claim
31 words
An assembly comprising apparatus according to any one of claims 11 to 20 in combination with, and located within, an outer shell having an inlet and outlet for said heating fluid.
Claim 24
Dependent Claim
105 words
A combination comprising: (i) an assembly according to claim 21, (ii) a secondary reformer external to said outer shell, (iii) means for supplying a gas containing free oxygen to said secondary reformer, (iv) first conduit means connecting the outlet of said secondary reformer with the inlet of said outer shell, (v) second conduit means communicating with the inlet of the, or each, tubular reactor for supplying a gas stream thereto from outside said outer shell, and (vi) third conduit means communicating with the outlet of the, or each, tubular reactor for delivering said gas stream, after passage through said tubular reactor, to said secondary reformer.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.