EP0159730A2
Expired / Lapsed
EP
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Process for the removal of sulphur compounds from off-gases
Assignee: Shell Internationale Research Maatschappij BV
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Filing: 1985-03-08
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Granted: —
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Expires: 2005-03-08
Abstract
Abstract Removal of sulphur compounds from the off-gas of a sulphur recovery unit of the Claus type, in which this off-gas is mixed with an H 2 S-rich gas to form a gas mixture having a higher H 2 S to S0 2 molar ratio than the off-gas, which gas mixture is passed at a temperature below 300° C over a Claus catalyst and a second off-gas is separated from the catalyst, said second off-gas is subsequently passed over a regenerable solid metal oxide absorbent to absorb H 2 S, spent metal oxide absorbent is regenerated, thereby producing a gas rich in sulphur compounds which is introduced into a sulphur recovery unit of the Claus type.
Inventors
- 👤 Ramalinga Ramamurthy
- 👤 Swan Tiong Sie
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 10:09
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86; B01D53/8603; B01D53/8612; B01D53/8615; B01D53/46; B01D53/48; B01D53/52; B01D53/523; C; C01; C01B; C01B17/00; C01B17/02; C01B17/04; C01B17/0404; C01B17/0456
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
188 words
A process for the removal of sulphur compounds from the off-gas of a sulphur recovery unit of the Claus type, which process comprises the following consecutive steps:- (a) mixing the said off-gas and a gas having a higher content of hydrogen sulphide than the said off-gas to form a gas mixture having an increased hydrogen sulphide to sulphur dioxide molar ratio compared to the off-gas, passing the mixture thus formed at a temperature below 300°C over a catalyst promoting the Claus reaction, and separating a second off-gas from the said catalyst; (b) passing the said second off-gas over a regenerable, solid metal oxide absorbent to absorb hydrogen sulphide with formation of a spent metal oxide absorbent and separating the unabsorbed portion of the second off-gas from the spent metal oxide absorbent: (c) regenerating the spent metal oxide absorbent, thereby producing regenerated absorbent and a gas rich in sulphur compounds; and (d) re-using in step (b) the regenerated absorbent obtained in step (e) for further hydrogen sulphide absorption and introducing the gas rich in sulphur compounds produced in step (c) into a sulphur recovery unit of the Claus type.
Claim 2
Dependent Claim
188 words
A process for the removal of sulphur compounds from the off-gas of a sulphur recovery unit of the Claus type, which process comprises the following consecutive steps:- (a) mixing the said off-gas and a gas having a higher content of hydrogen sulphide than the said off-gas to form a gas mixture having an increased hydrogen sulphide to sulphur dioxide molar ratio compared to the off-gas, passing the mixture thus formed at a temperature below 300°C over a catalyst promoting the Claus reaction, and separating a second off-gas from the said catalyst; (b) passing the said second off-gas over a regenerable, solid metal oxide absorbent to absorb hydrogen sulphide with formation of a spent metal oxide absorbent and separating the unabsorbed portion of the second off-gas from the spent metal oxide absorbent: (c) regenerating the spent metal oxide absorbent, thereby producing regenerated absorbent and a gas rich in sulphur compounds; and (d) re-using in step (b) the regenerated absorbent obtained in step (e) for further hydrogen sulphide absorption and introducing the gas rich in sulphur compounds produced in step (c) into a sulphur recovery unit of the Claus type.
Claim 3
Dependent Claim
25 words
A process as claimed in claim 1, in which the gas mixture is passed over the catalyst in step (a) at a temperature below 250°C.
Claim 4
Dependent Claim
36 words
A process as claimed in claim 1 or 2, in which use is made of a molar ratio H 2 S to S02 of at least 3:1 in the gas mixture being passed over the catalyst.
Claim 5
Dependent Claim
26 words
A process as claimed in claim 3, in which use is made of a molar ratio H 2 S to SO 2 of at least 4:1.
Claim 6
Dependent Claim
48 words
A process as claimed in any one of the preceding claims, in which a bleedstream of the hydrogen-sulphide containing gas being fed to the sulphur recovery unit is used as the gas having a higher content of hydrogen sulphide than the said off-gas of the sulphur recovery unit.
Claim 7
Dependent Claim
30 words
A process as claimed in any one of the preceding claims, in which use is made of an aluminium oxide or of bauxite as the catalyst used in step (a).
Claim 8
Dependent Claim
27 words
A process as claimed in any one of the preceding claims, in which step (a) is carried out in a catalytic stage of the sulphur recovery unit.
Claim 9
Dependent Claim
24 words
A process as claimed in claim 7, in which step (a) is carried out in the last catalytic stage of the sulphur recovery unit.
Claim 10
Dependent Claim
27 words
A process as claimed in any one of the claims 1-6, in which step (a) is carried out in a unit separate from the sulphur recovery unit.
Claim 11
Dependent Claim
19 words
A process as claimed in claim 9, in which step (b) is carried out at a temperature below 200°C.
Claim 12
Dependent Claim
20 words
A process as claimed in any one of the preceding claims, in which the metal oxide absorbent comprises zinc oxide.
Claim 13
Dependent Claim
18 words
A process as claimed in claim 11, in which the zinc oxide is combined with a carrier material.
Claim 14
Dependent Claim
15 words
A process as claimed in claim 12, in which the carrier material is silicium dioxide.
Claim 15
Dependent Claim
33 words
A process as claimed in claim 12, in which the carrier material is chosen from the group comprising oxides of copper, cadmium, titanium, zirconium, vanadium, chromium, molybdenum, tungsten, manganese, iron, cobalt and nickel.
Claim 16
Dependent Claim
30 words
A process as claimed in any one of the claims 11-14, in which the zinc oxide absorbent is combined with a zeolite having a pore size greater than 0.40 nm.
Claim 17
Dependent Claim
22 words
A process as claimed in any one of the claims 11-15, in which the zinc oxide absorbent is combined with molybdenum oxide.
Claim 18
Dependent Claim
29 words
A process for the removal of sulphur compounds from the off-gas of a sulphur recovery unit of the Claus type, substantially as hereinbefore described with reference to the Figure.
Claim 19
Dependent Claim
29 words
A process for the removal of sulphur compounds from the off-gas of a sulphur recovery unit of the Claus type, substantially as hereinbefore described with reference to the Figure.
References Cited (Backward Citations)
No citation records indexed.
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