Patent US3736698A successfully refreshed from Google Patents.
EP0157480A2
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EP
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Process for producing ammonia synthesis gas
Assignee: Imperial Chemical Industries Ltd
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Filing: 1985-02-15
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Granted: —
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Expires: 2005-02-15
Abstract
Abstract Ammonia synthesis gas is made from a raw gas comprising hydrogen, carbon dioxide and medium boiling point gases including nitrogen in excess of the proportion required in ammonia synthesis gas, by a pressure swing adsorption process characterised by feeding to the absorbent a raw gas in which hydrogen and total medium boiling point gases are present in a volume ratio in the range 1.25 to 2.5, and the medium boiling point gases comprise nitrogen to the extent of at least 90% v / v on the total of such gases. Preferred ways of making the raw gas, of ensuring purity of the product gas and of recovering useful heat are described..
Inventors
- 👤 Alwyn Pinto
- 👤 John Brian Hansen Johnson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 14:52
CPC Classifications
C; C01; C01B; C01B3/00; C01B3/02; C01B3/025; B; B01; B01D; B01D53/00; B01D53/02; B01D53/04; B01D53/047; B01D2253/00; B01D2253/10; B01D2253/102; B01D2253/106; B01D2257/00; B01D2257/10; B01D2257/104; B01D2257/11; B01D2257/50; B01D2257/504; B01D2257/70; B01D2257/702; B01D2257/7022; B01D2257/7025; B01D2257/80; B01D2259/00; B01D2259/40; B01D2259/40001; B01D2259/40011; B01D2259/40013; B01D2259/40015; B01D2259/4002; B01D2259/40022; B01D2259/40028; B01D2259/4003; B01D2259/40035; B01D2259/40037; B01D2259/40043; B01D2259/40045; B01D2259/4005; B01D2259/40052; B01D2259/40056; B01D2259/40058; B01D2259/40071; B01D2259/40073; B01D2259/40077; B01D2259/40081; B01D2259/401; B01D2259/404; B01D2259/406; B01D2259/4067; B01D53/26; B01D53/261; C01B2203/00; C01B2203/02; C01B2203/0205; C01B2203/0227; C01B2203/0233; C01B2203/0283; C01B2203/0288; C01B2203/04; C01B2203/042; C01B2203/043; C01B2203/0435; C01B2203/044; C01B2203/0445; C01B2203/0465; C01B2203/047; C01B2203/0475; C01B2203/0495; C01B2203/06; C01B2203/068; C01B2203/08; C01B2203/0805; C01B2203/0811; C01B2203/0816; C01B2203/0822; C01B2203/0827; C01B2203/0838; C01B2203/0844; C01B2203/0866; C01B2203/0872; C01B2203/0883; C01B2203/10; C01B2203/1041; C01B2203/1047; C01B2203/1052; C01B2203/1076; C01B2203/12; C01B2203/1205; C01B2203/1211; C01B2203/1235; C01B2203/1241; C01B2203/1276; C01B2203/14; C01B2203/146; C01B2203/147; C01B2203/148; C01B2203/80; C01B2203/82; C01B2203/84; Y; Y02; Y02C; Y02C20/00; Y02C20/20; Y02C20/40; Y02P; Y02P20/00; Y02P20/10; Y02P20/151; Y02P20/156
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
103 words
A pressure swing adsorption process for producing ammonia synthesis gas from a raw gas containing hydrogen, carbon dioxide and at least one medium boiling point gases selected from the class consisting of nitrogen, carbon monoxide, methane and argon, the nitrogen content being greater than that required in ammonia synthesis gas, characterised by feeding to the adsorbent a raw gas in which hydrogen and total medium boiling point gases are present in a volume ratio in the range 1025 to 2.5, and the medium boiling point gases comprise nitrogen to the extent of at least 90% v /v on the total of such gases.
Claim 2
Dependent Claim
103 words
A pressure swing adsorption process for producing ammonia synthesis gas from a raw gas containing hydrogen, carbon dioxide and at least one medium boiling point gases selected from the class consisting of nitrogen, carbon monoxide, methane and argon, the nitrogen content being greater than that required in ammonia synthesis gas, characterised by feeding to the adsorbent a raw gas in which hydrogen and total medium boiling point gases are present in a volume ratio in the range 1025 to 2.5, and the medium boiling point gases comprise nitrogen to the extent of at least 90% v /v on the total of such gases.
Claim 3
Dependent Claim
22 words
A process according to claim 1 in which the medium boiling point gases comprise nitrogen to the extent of at least 95%.
Claim 4
Dependent Claim
29 words
A process according to claim 1 or claim 2 in which the raw gas contains medium boiling point gases and carbon dioxide in a volume ratio 1.3 to 2.5.
Claim 5
Dependent Claim
27 words
A process according to claim 3 in which the composition of the raw gas is as represented by quadrilateral EFGH shown on the triangular diagram, fig. 1.
Claim 6
Dependent Claim
82 words
5 o A process according to any one of the preceding claims in which the pressure swing adsorption system used includes an adsorption step producing a product gas varying in composition with time between an initial and final relatively low H 2 /N 2 volume ratio and an intermediate relatively high H 2 /N 2 volume ratio, the integrated H 2 / N 2 volume ratio over the whole adsorption step being at the level required in the product ammonia synthesis gas.
Claim 7
Dependent Claim
32 words
A process according to claim 5 in which the adsorption pressure is in the range 30 to 40 bar abs. and is 10 to 15 times the purge and final dump pressure.
Claim 8
Dependent Claim
27 words
A process according to any one of the preceding claims in which the carbon monoxide content of the raw gas is under 0.5% v / v .
Claim 9
Dependent Claim
30 words
A process according to claim 7 in which the carbon monoxide content of the raw gas as decreased by selective catalytic oxidation or methanation before feeding it to the adsorbent.
Claim 10
Dependent Claim
104 words
A process according to any one of the preceding claims in which the raw gas is the product of (a) reacting a carbonaceous feedstock with steam and an O 2 -N 2 mixture using process conditions and reactant proportions so as to produce a crude gas in which the ratio by moles is in the range 1.25 to 2.5, especially 1.4 to 2.1 and the MB gas consists of N 2 to the extent of at least 90% v / v ; and (b) subjecting the crude gas to catalytic shift reaction with steam to convert CO substantially to C0 2 + H 2'
Claim 11
Dependent Claim
86 words
A process according to claim 9 in which stage (a) comprises (i) reacting a volatile hydrocarbon feedstock with steam over a catalyst heated externally to produce a gas containing CO, CO 2 , H2 and CH 4 ; (ii) reacting the resulting gas with the 0 2 -N 2 mixture adiabatically to convert CH 4 to CO + H 2 and introduce N 2 ; and (iii) obtaining the heat required for stage (i) by indirect heat exchange with the hot gas resulting from stage (ii).
Claim 12
Dependent Claim
25 words
A process according to claim 9 or claim 10 in which the catalytic shift reaction is operated in indirect heat exchange with water under pressure.
Claim 13
Dependent Claim
67 words
A process according to claim 11 in which the heat exchange is operated without producing external steam and the waste gas from pressure swing adsorption, containing carbon dioxide and combustibles, is used to power a gas expander producing at least part of the power required to compress the ammonia synthesis gas product and/or a gas taking part in stage (a) defined in claim 9 or claim 10.
References Cited (Backward Citations)
No citation records indexed.
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