WO2014204965A1 - Process for degassing condensed sulfur from a claus sulfur recovery system - Google Patents
Process for degassing condensed sulfur from a claus sulfur recovery system Download PDFInfo
- Publication number
- WO2014204965A1 WO2014204965A1 PCT/US2014/042748 US2014042748W WO2014204965A1 WO 2014204965 A1 WO2014204965 A1 WO 2014204965A1 US 2014042748 W US2014042748 W US 2014042748W WO 2014204965 A1 WO2014204965 A1 WO 2014204965A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sulfur
- contact zone
- process gas
- catalyst
- claus
- Prior art date
Links
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title claims abstract description 155
- 229910052717 sulfur Inorganic materials 0.000 title claims abstract description 129
- 239000011593 sulfur Substances 0.000 title claims abstract description 129
- 238000000034 method Methods 0.000 title claims abstract description 92
- 238000007872 degassing Methods 0.000 title claims abstract description 36
- 238000011084 recovery Methods 0.000 title description 23
- 239000007788 liquid Substances 0.000 claims abstract description 58
- 239000003054 catalyst Substances 0.000 claims abstract description 39
- 239000007789 gas Substances 0.000 claims description 67
- 238000006243 chemical reaction Methods 0.000 claims description 15
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 10
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 7
- 230000003197 catalytic effect Effects 0.000 claims description 7
- 239000002245 particle Substances 0.000 claims description 7
- 239000000919 ceramic Substances 0.000 claims description 3
- 239000006260 foam Substances 0.000 claims description 3
- 230000003009 desulfurizing effect Effects 0.000 claims description 2
- 238000006555 catalytic reaction Methods 0.000 claims 2
- 238000003860 storage Methods 0.000 abstract description 6
- 238000009877 rendering Methods 0.000 abstract 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 62
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 56
- 238000004519 manufacturing process Methods 0.000 description 10
- -1 DEGASSED Chemical compound 0.000 description 8
- 238000011065 in-situ storage Methods 0.000 description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 238000003756 stirring Methods 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 235000013980 iron oxide Nutrition 0.000 description 2
- 239000003345 natural gas Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 150000003464 sulfur compounds Chemical class 0.000 description 2
- 238000011282 treatment Methods 0.000 description 2
- 239000002918 waste heat Substances 0.000 description 2
- 238000013019 agitation Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000005587 bubbling Effects 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- VBMVTYDPPZVILR-UHFFFAOYSA-N iron(2+);oxygen(2-) Chemical class [O-2].[Fe+2] VBMVTYDPPZVILR-UHFFFAOYSA-N 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000003209 petroleum derivative Substances 0.000 description 1
- 229910000057 polysulfane Inorganic materials 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/02—Preparation of sulfur; Purification
- C01B17/021—Separation of sulfur from gases
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
- B01D5/0003—Condensation of vapours; Recovering volatile solvents by condensation by using heat-exchange surfaces for indirect contact between gases or vapours and the cooling medium
- B01D5/0012—Vertical tubes
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/02—Preparation of sulfur; Purification
- C01B17/04—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides
- C01B17/0404—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides by processes comprising a dry catalytic conversion of hydrogen sulfide-containing gases, e.g. the Claus process
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/02—Preparation of sulfur; Purification
- C01B17/04—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides
- C01B17/0404—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides by processes comprising a dry catalytic conversion of hydrogen sulfide-containing gases, e.g. the Claus process
- C01B17/0426—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides by processes comprising a dry catalytic conversion of hydrogen sulfide-containing gases, e.g. the Claus process characterised by the catalytic conversion
- C01B17/0439—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides by processes comprising a dry catalytic conversion of hydrogen sulfide-containing gases, e.g. the Claus process characterised by the catalytic conversion at least one catalyst bed operating below the dew-point of sulfur
Definitions
- This invention relates to the recovery of degassed sulfur from a Claus sulfur recovery plant and especially to substantially reducing the H 2 S content of liquid sulfur for the safe storage and transportation of liquid sulfur.
- the Claus process is a gas desulfurizing process for recovering elemental sulfur from gaseous hydrogen sulfide. It was first developed in the 1880's and has become an industry standard for refineries, chemical plants and natural gas processing plants. As petroleum and natural gas is tending to contain ever increasing amounts of sulfur compounds while fuel regulations are tending to mandate less allowable sulfur in fuel, Claus processes become increasingly important
- a Claus plant which is a multi-step process within a larger industrial plant is arranged to recover sulfur from gaseous hydrogen sulfide.
- elemental sulfur is produced by a thermal step and several catalytic steps.
- Elemental sulfur is separated from the Claus plant as a liquid at one or more condensers.
- H 2 S emanating from liquid sulfur storage may become a fugitive emission in an area that is closely monitored for environmental compliance.
- up to half of the reported emissions from a Claus sulfur recovery plant and Claus Tail Gas Cleanup unit can come from H 2 S emanating from liquid sulfur in storage. Without degassing operations or adequate capture and disposal technology, these additional emissions may limit the sulfur processing capability of the Claus/TGU (Tail Gas Unit) unit.
- the invention more particularly relates to a process for producing liquid sulfur that is degassed of H2S.
- the process includes a sulfur degassing catalyst and liquid sulfur in a vessel wherein the sulfur degassing catalyst and liquid sulfur define a contact zone and condensed products are directed to the vessel from a Claus plant into the contact zone of the vessel.
- These condensed products include elemental sulfur, dissolved H 2 S and H 2 S X where x>2.
- the conversion of H 2 S X is catalyzed on the surface of the sulfur degassing catalyst to form H 2 S and elemental sulfur and process gas from the Claus plant is directed at an elevated pressure into the contact zone of the vessel to agitate the sulfur degassing catalyst and liquid sulfur.
- the process gas also carries H 2 S that has formed on the surface of the sulfur degassing catalyst away from the sulfur degassing catalyst.
- the process gas includes H 2 S prior to entering the vessel.
- the processes gases along with H 2 S from the contact zone are exhausted for further processing in the Claus plant and liquid sulfur that is degassed of H 2 S is extracted from the contact zone.
- FIG. 1 is a flow diagram showing a basic and conventional Claus sulfur recovery system
- Figure 2 is a flow diagram showing liquid sulfur being degassed of H 2 S
- Figure 3 is a flow diagram of the vessel connected to the Claus process.
- Figure 4 is a flow diagram of an alternative embodiment showing the liquid sulfur being degassed of H 2 S.
- FIG. 1 a line diagram for a conventional Claus Sulfur Recovery Plant is generally indicated by the numeral 10.
- Claus Plants have been in use for more than a century at petroleum refineries to remove sulfur from gases containing H 2 S.
- gas having sulfur typically in the form of H 2 S
- a burner 15 along with reaction furnace 18 are provided to burn and oxidize at least part of the H 2 S to elemental sulfur S0 2 and water wherein the reaction is:
- a sulfur degassing vessel 60 is arranged to receive the liquid sulfur from liquid discharge conduits 25 and 35 at a lower portion of the vessel 60 or at the bottom of the vessel 60.
- liquid sulfur with a contained catalyst 62 held within a contact zone 65 that is generally above the lower portion of the vessel 60.
- a degassed liquid sulfur discharge line 66 is arrange to remove liquid sulfur above the contact zone such that liquid sulfur entering the vessel 60 must pass completely through the contact zone 65 or at least through a substantial portion of the contact zone 65.
- the catalyst 62 may take one of several forms. The first form is a plurality of high surface area alumina particles (spheres, extrudates, etc.) constrained to prevent being removed or carried away by sulfur flow from the vessel 60.
- a second form is a plurality of similarly constrained high surface area alumina particles impregnated with iron oxides.
- a third form is one or more low surface area alumina porous ceramic foam supports coated with high surface alumina particles with or without impregnated iron oxide.
- the catalyst 62 converts H 2 S X to H 2 S and elemental sulfur. Reducing the content of H 2 S X at this stage of the production of liquid sulfur has been found to substantially reduce the tendency of stored liquid sulfur to slowly yield H 2 S gas.
- the productivity of the catalyst 62 is enhanced by agitation, especially by gas.
- the gas used to stir the liquid in the contact zone 65 is process gas from the Claus process delivered through conduit 28A of H 2 S containing gas.
- a metering valve may be arranged so that a small amount of process gas may be injected near the bottom of the vessel in a sparger 63 to agitate the liquid and the catalyst 62 to carry produced H 2 S back to the Claus Sulfur Recovery Plant 10.
- the process gas may alternatively be taken off conduit 38 as shown by dotted line conduit 28B.
- the process gas rejoins the Claus process at conduit 48 via conduit 48A.
- the process gas may optionally be arranged to rejoin the Claus process at conduit 38 as shown by dotted line 38 A.
- the process gas may optionally be arranged to rejoin the Claus process further along the system such as at conduit 51 A.
- This arrangement is shown by dotted line 48B and may be preferred if the source of the process gas used in vessel 60 comes from conduit 38 via conduit 28B. While the process gas from the vessel 60 will not have been subjected to all of the successive treatments in the catalytic reactors 31, 41 and 51, it may have some vaporous elemental sulfur that could be condensed in condenser 52 and may be subjected to further sulfur removal treatment in a tail gas unit, which are conventional in Claus plants.
- One additional side reaction occurring in the contact zone 65 worth mentioning is additional conversion of H 2 S to elemental sulfur.
- the process gas includes some S0 2 and may reaction on the surface of the catalyst with H 2 S that may be condensed in the liquid sulfur, emanating from the liquid sulfur by the decomposition of H 2 S X , or contained in the process gas.
- the process gas generally includes H2S.
- Process gases in line 28 may contain about 4% to about 9% by volume H 2 S and typically about 8% by volume H 2 S.
- Process gases in line 38 typically comprise less H 2 S, but certainly have sufficient pressure to agitate the catalyst 62 and return to the Claus process 10.
- Process gases in line 38 may have between 2% to 5% H 2 S by volume and typically about 4% by volume H 2 S.
- Process gases in line 48 still retain sufficient pressure to be used to agitate the catalyst 62 and has a lower H 2 S content being about 0.5% H 2 S to about 3% H 2 S by volume and typically about 1% H 2 S to about 2% H 2 S by volume.
- the vessel 60 may optionally be arranged to receive liquid sulfur discharged through drains 45 and 55 for degassing.
- the liquid sulfur discharge lines 45 and 55 are combined with the degassed liquid sulfur in line 66. It has been found that such small streams of liquid sulfur really do not contain much H 2 S X that needs degassing. Most of the liquid sulfur is gathered from the first two condensers 22 and 32.
- the liquid sulfur may be received at the top of the vessel 60 and liquid elemental sulfur having the sulfanes removed may be withdrawn at the bottom of the vessel 60.
- the sulfur is travelling counter to the flow of the process gas through the reaction zone 65.
- the catalyst zone 65 is shown as being liquid continuous, whereas, in the alternative embodiment shown in Figure 4, the catalyst zone may be gas continuous with the liquid sulfur trickling down through the contact zone 65.
Abstract
A process of producing degassed liquid sulfur using process gas containing H2S to agitate the liquid sulfur being degassed while in contact with a degassing catalyst. Process gas is less costly and less complicated and quickly accomplishes substantial degassing rendering the liquid sulfur much safer in storage and transportation.
Description
PROCESS FOR DEGASSING CONDENSED SULFUR FROM A CLAUS SULFUR
RECOVERY SYSTEM
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a PCT International application which claims the benefit of and priority to U.S. Provisional Application Serial No. 61/837,927 filed June 21, 2013 entitled "APPARATUS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULPHIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Patent Application Serial No. 14/303,913 filed June 13, 2014 entitled "APPARATUS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULFIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Provisional Application Ser. No. 61/837,944 filed June 21, 2013 entitled "APPARATUS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULPHIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Patent Application Serial No. 14/303,937 filed June 13, 2014 entitled "APPARATUS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULFIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Provisional Application Ser. No. 61/837,950 filed June 21, 2013 entitled "PROCESS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULPHIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Patent Application Serial No. 14/303,946 filed June 13, 2014 entitled "PROCESS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULFIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Provisional Application Ser. No. 61/837,958 filed June 21, 2013 entitled "PROCESS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULPHIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Patent Application Serial No. 14/304,286 filed June 13, 2014 entitled "PROCESS FOR IN-SITU PRODUCTION OF LOW DISSOLVED HYDROGEN SULFIDE, DEGASSED, SULFUR FROM CLAUS SULFUR RECOVERY," U.S. Provisional Application Ser. No. 62/010,766 filed June 11, 2014 entitled "PROCESS FOR DEGASSING CONDENSED SULFUR FROM A CLAUS SULFUR RECOVERY SYSTEM", and U.S. Patent Application Serial No. 14/304,306 filed June 13, 2014 entitled "PROCESS FOR DEGASSING CONDENSED SULFUR FROM A CLAUS SULFUR RECOVERY SYSTEM."
FIELD OF THE INVENTION
[0002] This invention relates to the recovery of degassed sulfur from a Claus sulfur recovery plant and especially to substantially reducing the H2S content of liquid sulfur for the safe storage and transportation of liquid sulfur.
BACKGROUND OF THE INVENTION
[0003] The Claus process is a gas desulfurizing process for recovering elemental sulfur from gaseous hydrogen sulfide. It was first developed in the 1880's and has become an industry standard for refineries, chemical plants and natural gas processing plants. As petroleum and natural gas is tending to contain ever increasing amounts of sulfur compounds while fuel regulations are tending to mandate less allowable sulfur in fuel, Claus processes become increasingly important
[0004] A Claus plant, which is a multi-step process within a larger industrial plant is arranged to recover sulfur from gaseous hydrogen sulfide. Typically, elemental sulfur is produced by a thermal step and several catalytic steps. Elemental sulfur is separated from the Claus plant as a liquid at one or more condensers.
[0005] While current sulfur condensers have proven satisfactory for condensing sulfur, there is a need for improvement in the quality of the sulfur condensed. The problem is that the condensed sulfur includes dissolved H2S. Over an extended time, the H2S will eventually disassociate from the liquid sulfur and accumulate as a toxic and flammable gas in vapor spaces at the top of the storage or transport vessels. Since an unsafe condition is possible until the sulfur is fully degassed of dissolved H2S, precautionary steps are required prior to opening a sulfur vessel and while transferring liquid sulfur from one vessel to another.
[0006] It has been found that it is the nature of a liquid sulfur produced in a sulfur condenser process that reactant hydrogen sulfide (H2S) is incorporated into the sulfur as simple dissolved H2S and also as chemically bound with sulfur in the form what is sometimes called a sulfane or polysulfane. Sulfane is H2SX, (with x>l). H2SX will convert back to H2S and elemental sulfur in time through an equilibrium reaction which may be accelerated with a catalyst. This is a known problem and most efforts to remove H2S from the elemental sulfur include bubbling various gases such as air and preferably inert gases such as nitrogen and carbon dioxide through the liquid sulfur while in a catalyst bed. This degassing process, while necessary, takes time and
adds to the expense of capturing sulfur from refineries, gas plants and chemical plants that deal with sulfur.
[0007] Thorough degassing is imperative as capturing and disposing of H2S that is emanating from liquid sulfur storage is another issue. If the elemental sulfur is not adequately degassed, H2S emanating from liquid sulfur storage may become a fugitive emission in an area that is closely monitored for environmental compliance. In some instances, up to half of the reported emissions from a Claus sulfur recovery plant and Claus Tail Gas Cleanup unit can come from H2S emanating from liquid sulfur in storage. Without degassing operations or adequate capture and disposal technology, these additional emissions may limit the sulfur processing capability of the Claus/TGU (Tail Gas Unit) unit.
[0008] Technology is needed to reduce costs and overcome and resolve these problems without creating new disadvantages.
BRIEF SUMMARY OF THE DISCLOSURE
[0009] The invention more particularly relates to a process for producing liquid sulfur that is degassed of H2S. The process includes a sulfur degassing catalyst and liquid sulfur in a vessel wherein the sulfur degassing catalyst and liquid sulfur define a contact zone and condensed products are directed to the vessel from a Claus plant into the contact zone of the vessel. These condensed products include elemental sulfur, dissolved H2S and H2SX where x>2. The conversion of H2SX is catalyzed on the surface of the sulfur degassing catalyst to form H2S and elemental sulfur and process gas from the Claus plant is directed at an elevated pressure into the contact zone of the vessel to agitate the sulfur degassing catalyst and liquid sulfur. The process gas also carries H2S that has formed on the surface of the sulfur degassing catalyst away from the sulfur degassing catalyst. The process gas includes H2S prior to entering the vessel. The processes gases along with H2S from the contact zone are exhausted for further processing in the Claus plant and liquid sulfur that is degassed of H2S is extracted from the contact zone.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] A more complete understanding of the present invention and benefits thereof may be acquired by referring to the follow description taken in conjunction with the accompanying drawings in which:
[0011] Figure 1 is a flow diagram showing a basic and conventional Claus sulfur recovery system;
[0012] Figure 2 is a flow diagram showing liquid sulfur being degassed of H2S;
[0013] Figure 3 is a flow diagram of the vessel connected to the Claus process; and
[0014] Figure 4 is a flow diagram of an alternative embodiment showing the liquid sulfur being degassed of H2S.
DETAILED DESCRIPTION
[0015] Turning now to the detailed description of the preferred arrangement or arrangements of the present invention, it should be understood that the inventive features and concepts may be manifested in other arrangements and that the scope of the invention is not limited to the embodiments described or illustrated. The scope of the invention is intended only to be limited by the scope of the claims that follow.
[0016] Referring now to Figure 1, a line diagram for a conventional Claus Sulfur Recovery Plant is generally indicated by the numeral 10. Claus Plants have been in use for more than a century at petroleum refineries to remove sulfur from gases containing H2S. Undertaking a brief explanation of a conventional Claus Plant, referring to Claus Sulfur Recovery Plant 10, gas having sulfur, typically in the form of H2S , enters via conduit 12. A burner 15 along with reaction furnace 18 are provided to burn and oxidize at least part of the H2S to elemental sulfur S02 and water wherein the reaction is:
[0017] 10 H2S + 5 02→ 2 H2S + S02 + 7/2 S2 + 8 H20.
[0018] These very hot gases and vapors are cooled down in a waste heat boiler 19 and a first condenser 22 where the elemental sulfur is condensed and removed at liquid discharge conduit 25. Cooling water is provided to both the waste heat boiler 19 and to the condenser 22, as shown at inlet 23 to make steam, as shown at outlet 24, for use in making electricity or elsewhere in the in the Claus Sulfur Recovery Plant 10 or in the larger industrial plant that is not shown. The remaining gases from the first condenser 22 are directed through the gas conduit 28 to reheater 30 where the gases are reheated and then delivered to a catalytic conversion to elemental sulfur for converting remaining H2S and S02 to elemental sulfur. The chemical process is generally described as follows:
[0019] 2 H2S + S02→ 3 S + 2 H20.
[0020] Again, the process gases are cooled in the second sulfur condenser 32 so that elemental sulfur may be condensed to a liquid and removed at the second liquid discharge conduit 35. The gases are conventionally directed by a conduit 38 to further sulfur recovery steps including catalytic reactor 41 and 51 to recover liquid sulfur at discharge conduits 45 and 55.
[0021] It should be noted that more thorough descriptions of a Claus system may be found in many other places and there are doubtless variations known in the art. This description has been presented simply to describe the improvement related to degassing the liquid sulfur acquired by most any Claus system.
[0022] Referring now to Figure 2, a sulfur degassing vessel 60 is arranged to receive the liquid sulfur from liquid discharge conduits 25 and 35 at a lower portion of the vessel 60 or at the bottom of the vessel 60. Inside the vessel 60 is liquid sulfur with a contained catalyst 62 held within a contact zone 65 that is generally above the lower portion of the vessel 60. A degassed liquid sulfur discharge line 66 is arrange to remove liquid sulfur above the contact zone such that liquid sulfur entering the vessel 60 must pass completely through the contact zone 65 or at least through a substantial portion of the contact zone 65. The catalyst 62 may take one of several forms. The first form is a plurality of high surface area alumina particles (spheres, extrudates, etc.) constrained to prevent being removed or carried away by sulfur flow from the vessel 60. A second form is a plurality of similarly constrained high surface area alumina particles impregnated with iron oxides. A third form is one or more low surface area alumina porous ceramic foam supports coated with high surface alumina particles with or without impregnated iron oxide.
[0023] The catalyst 62 converts H2SX to H2S and elemental sulfur. Reducing the content of H2SX at this stage of the production of liquid sulfur has been found to substantially reduce the tendency of stored liquid sulfur to slowly yield H2S gas. The productivity of the catalyst 62 is enhanced by agitation, especially by gas. In the present invention, as distinguished from prior known systems, the gas used to stir the liquid in the contact zone 65 is process gas from the Claus process delivered through conduit 28A of H2S containing gas. A metering valve may be arranged so that a small amount of process gas may be injected near the bottom of the vessel in a sparger 63 to agitate the liquid and the catalyst 62 to carry produced H2S back to the Claus Sulfur
Recovery Plant 10. The process gas may alternatively be taken off conduit 38 as shown by dotted line conduit 28B.
[0024] Once the gas has passed through the vessel 60, it exits at exit conduit 68 and rejoins the Claus process downstream of the source of the process gas at conduit 28. In the preferred arrangement, the process gas rejoins the Claus process at conduit 48 via conduit 48A. It should be noted that the process gas may optionally be arranged to rejoin the Claus process at conduit 38 as shown by dotted line 38 A. However, there is a more significant pressure drop between conduits 28 and 48 to allow for more vigorous stirring of the catalyst 62 by the process gas from sparger 63. For even more vigorous stirring, the process gas may optionally be arranged to rejoin the Claus process further along the system such as at conduit 51 A. This arrangement is shown by dotted line 48B and may be preferred if the source of the process gas used in vessel 60 comes from conduit 38 via conduit 28B. While the process gas from the vessel 60 will not have been subjected to all of the successive treatments in the catalytic reactors 31, 41 and 51, it may have some vaporous elemental sulfur that could be condensed in condenser 52 and may be subjected to further sulfur removal treatment in a tail gas unit, which are conventional in Claus plants.
[0025] One additional side reaction occurring in the contact zone 65 worth mentioning is additional conversion of H2S to elemental sulfur. The process gas includes some S02 and may reaction on the surface of the catalyst with H2S that may be condensed in the liquid sulfur, emanating from the liquid sulfur by the decomposition of H2SX, or contained in the process gas. This reaction is the same chemical reaction occurring in the Claus process and is generally described as: 2 H2S + S02 = 3/x Sx + 2 H20. Having additional active catalyst for this chemical reaction to occur yields more liquid sulfur separated from the industrial process and less sulfur compounds in process gas.
[0026] It is noted that it has long been recognized that the catalytic process occurring in contact zone 65 is an equilibrium reaction and therefore, gases that have been used for agitating the catalyst always exclude H2S. This is more expensive than simply using a side stream of process gas. And, the process gas includes enough H2S to warrant further sulfur recovery steps so that H2S recovered in the vessel 60 is simply and efficiently disposed. As compared to an arrangement using air or nitrogen, the air and nitrogen will have acquired small amounts of H2S and elemental sulfur vapor that must be handled. These gases usually must be directed to a part
of the sulfur recovery unit where combustion can convert the elemental sulfur to S02 to avoid plugging the vent line from the process either contributing additional S02 emissions or requiring recycling with some motive fluid such as air or steam. This adds additional costs to operating a Claus process.
[0027] The process gas, as noted above generally includes H2S. Process gases in line 28 may contain about 4% to about 9% by volume H2S and typically about 8% by volume H2S. Process gases in line 38 typically comprise less H2S, but certainly have sufficient pressure to agitate the catalyst 62 and return to the Claus process 10. Process gases in line 38 may have between 2% to 5% H2S by volume and typically about 4% by volume H2S. Process gases in line 48 still retain sufficient pressure to be used to agitate the catalyst 62 and has a lower H2S content being about 0.5% H2S to about 3% H2S by volume and typically about 1% H2S to about 2% H2S by volume.
[0028] The full Claus process with the vessel 60 is generally shown in Figure 3 showing the side stream of process gas being taken from line 28 and being carried through the vessel 60 and back into the Claus process at line 38.
[0029] The vessel 60 may optionally be arranged to receive liquid sulfur discharged through drains 45 and 55 for degassing. In the preferred arrangement, the liquid sulfur discharge lines 45 and 55 are combined with the degassed liquid sulfur in line 66. It has been found that such small streams of liquid sulfur really do not contain much H2SX that needs degassing. Most of the liquid sulfur is gathered from the first two condensers 22 and 32.
[0030] In an alternative embodiment shown in Figure 4, the liquid sulfur may be received at the top of the vessel 60 and liquid elemental sulfur having the sulfanes removed may be withdrawn at the bottom of the vessel 60. In this embodiment, the sulfur is travelling counter to the flow of the process gas through the reaction zone 65. In Figure 2, the catalyst zone 65 is shown as being liquid continuous, whereas, in the alternative embodiment shown in Figure 4, the catalyst zone may be gas continuous with the liquid sulfur trickling down through the contact zone 65.
[0031] Although the systems and processes described herein have been described in detail, it should be understood that various changes, substitutions, and alterations can be made without departing from the spirit and scope of the invention as defined by the following claims. Those skilled in the art may be able to study the preferred embodiments and identify other ways to
practice the invention that are not exactly as described herein. It is the intent of the inventors that variations and equivalents of the invention are within the scope of the claims while the description, abstract and drawings are not to be used to limit the scope of the invention. The invention is specifically intended to be as broad as the claims below and their equivalents.
Claims
1. A process for producing liquid sulfur that is degassed of H2S, wherein the process comprises:
a) providing a sulfur degassing catalyst and liquid sulfur into a vessel wherein the sulfur degassing catalyst and liquid sulfur define a contact zone;
b) directing condensed products from a Claus plant into the contact zone of the vessel wherein the condensed products include elemental sulfur, dissolved H2S and H2SX where x≥2;
c) catalyzing the conversion of H2SX on the surface of the sulfur degassing catalyst to form H2S and elemental sulfur;
d) directing a process gas from the Claus plant at an elevated pressure into the contact zone of the vessel to agitate the sulfur degassing catalyst and liquid sulfur and carry H2S that has formed on the surface of the sulfur degassing catalyst away from the sulfur degassing catalyst; wherein the process gas includes H2S;
e) exhausting the processes gases along with H2S from the contact zone for further processing in the Claus plant; and
f) extracting liquid sulfur that is degassed of H2S from the contact zone.
A process for producing liquid sulfur that is degassed of H2S, wherein the process comprises:
a) providing a Claus plant for desulfurizing H2S containing gases, wherein the Claus plant includes a number of components such as a burner for converting some H2S to S02 along with elevated pressure process gas, a catalytic reaction furnace for converting at least some H2S and S02 to elemental sulfur, a first condenser for condensing the sulfur from the process gas exiting the catalytic reaction furnace, at least one additional catalytic reactor for converting a portion of the H2S in the process gas from the first condenser to elemental sulfur, a second condenser for condensing the sulfur in the gases exiting the one additional catalytic reactor; b) providing a sulfur degassing catalyst and liquid sulfur into a vessel wherein the sulfur degassing catalyst and liquid sulfur define a contact zone;
b) directing condensed products from at least one condenser of the Claus plant to the vessel, wherein the condensed products include elemental sulfur, dissolved H2S and H2SX where x≥2;
c) catalyzing the conversion of H2SX on the surface of the sulfur degassing catalyst in the contact zone to form H2S and elemental sulfur;
d) directing process gas from the Claus plant at elevated pressure into the contact zone of the vessel to agitate the sulfur degassing catalyst and liquid sulfur and carry H2S that has formed on the surface of the sulfur degassing catalyst away from the sulfur degassing catalyst; wherein the process gas includes H2S;
e) exhausting the processes gas along with H2S from the contact zone for further processing in the Claus plant; and
f) extracting liquid sulfur that is degassed of H2S from the contact zone.
The process according to Claims 1 or 2, wherein the step of providing a sulfur degassing catalyst comprises providing a plurality of high surface area alumina particles constrained to prevent being removed or carried away from the contact zone.
4. The process according to Claim 3, wherein the step of providing a sulfur degassing catalyst further comprises providing a plurality of high surface area alumina particles impregnated with iron oxide.
5. The process according to Claims 1 or 2, wherein the step of providing a sulfur degassing catalyst comprises providing one or more low surface area alumina porous ceramic foam supports coated with high surface alumina particles.
6. The process according to Claim 5, wherein the step of providing a sulfur degassing catalyst further comprises providing one or more low surface area alumina porous ceramic foam supports coated with high surface alumina particles that is impregnated with iron oxide.
7. The process according to Claims 1 or 2, wherein the process gas directed into the contact zone includes at least 0.5% H2S by volume.
8. The process according to Claims 1 or 2, wherein the process gas directed into the contact zone includes at least 1.0% H2S by volume.
9. The process according to Claims 1 or 2, wherein the process gas directed into the contact zone includes at least 2.0% H2S by volume.
10. The process according to Claims 1 or 2, wherein the process gas directed into the contact zone includes at least 3.0% H2S by volume.
11. The process according to Claims 1 or 2, wherein the process gas directed into the contact zone includes at least 4.0%> H2S by volume.
12. The process according to Claims 1 or 2, wherein the process gas directed into the contact zone includes at least 5.0% H2S by volume up to about 9%.
13. The process according to Claims 1 or 2, the Claus process includes at least three condensers, but only the liquid sulfur from the first two condensers are subject to degassing in the contact zone.
The process according to Claims 1 or 2, further including converting H2S to elemental sulfur by reacting on the surface of the catalyst with S02 in the process gas by the following reaction: 2 H2S + S02O 3/x Sx + 2 H20.
Applications Claiming Priority (20)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201361837944P | 2013-06-21 | 2013-06-21 | |
US201361837927P | 2013-06-21 | 2013-06-21 | |
US201361837958P | 2013-06-21 | 2013-06-21 | |
US201361837950P | 2013-06-21 | 2013-06-21 | |
US61/837,950 | 2013-06-21 | ||
US61/837,958 | 2013-06-21 | ||
US61/837,944 | 2013-06-21 | ||
US61/837,927 | 2013-06-21 | ||
US201462010766P | 2014-06-11 | 2014-06-11 | |
US62/010,766 | 2014-06-11 | ||
US14/304,286 | 2014-06-13 | ||
US14/303,937 US9789433B2 (en) | 2013-06-21 | 2014-06-13 | Apparatus for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from Claus sulfur recovery |
US14/303,937 | 2014-06-13 | ||
US14/304,306 | 2014-06-13 | ||
US14/303,913 US9757677B2 (en) | 2013-06-21 | 2014-06-13 | Apparatus for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from Claus sulfur recovery |
US14/303,946 US9192887B2 (en) | 2013-06-21 | 2014-06-13 | Process for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from claus sulfur recovery |
US14/304,306 US9138675B2 (en) | 2013-06-21 | 2014-06-13 | Process for degassing condensed sulfur from a claus sulfur recovery system |
US14/303,946 | 2014-06-13 | ||
US14/304,286 US9205364B2 (en) | 2013-06-21 | 2014-06-13 | Process for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from Claus sulfur recovery |
US14/303,913 | 2014-06-13 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2014204965A1 true WO2014204965A1 (en) | 2014-12-24 |
Family
ID=52105182
Family Applications (5)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2014/042709 WO2014204943A1 (en) | 2013-06-21 | 2014-06-17 | Vertical sulfur condenser for claus unit |
PCT/US2014/042748 WO2014204965A1 (en) | 2013-06-21 | 2014-06-17 | Process for degassing condensed sulfur from a claus sulfur recovery system |
PCT/US2014/042717 WO2014204946A1 (en) | 2013-06-21 | 2014-06-17 | Apparatus for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from claus sulfur recovery |
PCT/US2014/042725 WO2014204953A1 (en) | 2013-06-21 | 2014-06-17 | Process for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from claus sulfur recovery |
PCT/US2014/042776 WO2014204986A1 (en) | 2013-06-21 | 2014-06-17 | Process for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from claus sulfur recovery |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2014/042709 WO2014204943A1 (en) | 2013-06-21 | 2014-06-17 | Vertical sulfur condenser for claus unit |
Family Applications After (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2014/042717 WO2014204946A1 (en) | 2013-06-21 | 2014-06-17 | Apparatus for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from claus sulfur recovery |
PCT/US2014/042725 WO2014204953A1 (en) | 2013-06-21 | 2014-06-17 | Process for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from claus sulfur recovery |
PCT/US2014/042776 WO2014204986A1 (en) | 2013-06-21 | 2014-06-17 | Process for in-situ production of low dissolved hydrogen sulfide, degassed, sulfur from claus sulfur recovery |
Country Status (1)
Country | Link |
---|---|
WO (5) | WO2014204943A1 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111841234A (en) * | 2019-04-26 | 2020-10-30 | 宁德时代新能源科技股份有限公司 | Continuous sulfur recovery equipment and continuous sulfur recovery method |
CN110182764B (en) * | 2019-05-13 | 2021-03-23 | 中国神华煤制油化工有限公司 | Sulfur recovery device and sulfur recovery method |
CN112717475A (en) * | 2019-10-28 | 2021-04-30 | 中国石油化工股份有限公司 | Sulfur sealing equipment for sulfur recovery device and sulfur sealing method |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3939250A (en) * | 1972-06-29 | 1976-02-17 | Rhone-Poulenc Industries | Method of treating residual gases containing various compounds of sulphur |
US4508699A (en) * | 1984-01-13 | 1985-04-02 | Schoofs, Inc. | Claus process improvement |
US4729887A (en) * | 1985-08-16 | 1988-03-08 | Amoco Corporation | Process and apparatus for degassing sulfur |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2049160A (en) * | 1932-03-31 | 1936-07-28 | Guggenheim Brothers | Sulphur condenser |
US3607132A (en) * | 1969-09-05 | 1971-09-21 | Amoco Prod Co | Vertical sulfur recovery plant |
FR2601351B1 (en) * | 1986-07-10 | 1990-09-14 | Elf Aquitaine | PROCESS FOR THE RAPID REMOVAL OF HYDROGEN SULFIDE CONTAINED IN LIQUID SULFUR AND CATALYTIC SYSTEM FOR USE IN ITS IMPLEMENTATION. |
US4935221A (en) * | 1988-06-13 | 1990-06-19 | Air Products And Chemicals, Inc. | Water condenser/separator systems for Claus processes |
US5015459A (en) * | 1989-11-30 | 1991-05-14 | Amoco Corporation | High pressure-low pressure steam system for extended Claus sulfur recovery plant |
US5015460A (en) * | 1989-11-30 | 1991-05-14 | Amoco Corporation | Condenser-reactor switching units for extended Claus process |
US7357908B2 (en) * | 2000-12-18 | 2008-04-15 | Conocophillips Company | Apparatus and catalytic partial oxidation process for recovering sulfur from an H2S-containing gas stream |
US7501111B2 (en) * | 2006-08-25 | 2009-03-10 | Conoco Phillips Company | Increased capacity sulfur recovery plant and process for recovering elemental sulfur |
-
2014
- 2014-06-17 WO PCT/US2014/042709 patent/WO2014204943A1/en active Application Filing
- 2014-06-17 WO PCT/US2014/042748 patent/WO2014204965A1/en active Application Filing
- 2014-06-17 WO PCT/US2014/042717 patent/WO2014204946A1/en active Application Filing
- 2014-06-17 WO PCT/US2014/042725 patent/WO2014204953A1/en active Application Filing
- 2014-06-17 WO PCT/US2014/042776 patent/WO2014204986A1/en active Application Filing
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3939250A (en) * | 1972-06-29 | 1976-02-17 | Rhone-Poulenc Industries | Method of treating residual gases containing various compounds of sulphur |
US4508699A (en) * | 1984-01-13 | 1985-04-02 | Schoofs, Inc. | Claus process improvement |
US4729887A (en) * | 1985-08-16 | 1988-03-08 | Amoco Corporation | Process and apparatus for degassing sulfur |
Non-Patent Citations (1)
Title |
---|
HALDOR TOPSOE.: "Claus unit. Tail gas treatment catalysts.", 2009, Retrieved from the Internet <URL:http://www.topsoe.com/business_areas/refining/~/media/PDF%20files/Refining/topsoe_claus_tai_aug09_low_res.ashx> [retrieved on 20140910] * |
Also Published As
Publication number | Publication date |
---|---|
WO2014204986A1 (en) | 2014-12-24 |
WO2014204946A1 (en) | 2014-12-24 |
WO2014204953A1 (en) | 2014-12-24 |
WO2014204943A1 (en) | 2014-12-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9138675B2 (en) | Process for degassing condensed sulfur from a claus sulfur recovery system | |
RU2438764C2 (en) | High-efficiency method to recover sulfur from sulfur-containing gases | |
US8545793B2 (en) | Device and method for condensing, separating, and storing liquid sulfur in a Claus plant | |
US9758376B2 (en) | Process for degassing condensed sulfur from a Claus sulfur recovery system | |
EA029442B1 (en) | Sulphuric acid production with recycle of desulphurized gas | |
JP2018512360A (en) | High-efficiency degassing method for hydrogen sulfide in liquid sulfur | |
KR101538341B1 (en) | System for removing high hydrogen sulfide using iron chelate aqueous solution | |
WO2014204965A1 (en) | Process for degassing condensed sulfur from a claus sulfur recovery system | |
EP1864947A2 (en) | Process for the recovery of sulfuric acid | |
US9067166B2 (en) | Process for the removal of hydrogen sulfide from a gas stream | |
Spatolisano et al. | Middle scale hydrogen sulphide conversion and valorisation technologies: a review | |
WO2014132087A1 (en) | Method for removing sulphur dioxide from gas streams, using titanium dioxide as catalyst | |
RU2474533C1 (en) | Method of producing elementary sulphur from sulphur dioxide-containing exhaust gas | |
US9573081B2 (en) | Process for degassing condensed sulfur from a claus sulfur recovery system | |
WO2016077746A1 (en) | Degassing system and device for degassing liquid sulfur | |
RU2279909C2 (en) | Method of treatment of the discharge gases in the processes of desulphurization and the installation for the method realization (versions) | |
KR19980703355A (en) | Liquid phase conversion of sulfur dioxide to sulfuric acid | |
US9987591B2 (en) | Method for removing sulphur dioxide from gas streams, using titanium dioxide as catalyst | |
EA026172B1 (en) | Staged combustion of combustible sulphur-containing effluents with recovery of the sulphur in the claus process | |
US10508034B2 (en) | Extended thermal stage sulfur recovery process | |
CA2920747C (en) | Process and apparatus for the treatment of gases comprising hydrogen sulphide | |
RU2800865C1 (en) | Staged combustion device for sulfur recovery using pure oxygen and method for its recovery | |
EP0674598A1 (en) | Method and apparatus for treating a flow of gas containing oxidized sulphur compounds. | |
WO2019205055A1 (en) | Method and device for combining tail gas circulation of low temperature methanol washing unit and plurality of sets of claus units | |
US7578984B2 (en) | Regeneration of caustic solutions |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 14814155 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 14814155 Country of ref document: EP Kind code of ref document: A1 |