JPH06504949A - Treatment of acid gas using hybrid membrane separation system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Processing of acid gas using a hybrid membrane separation system The present invention generally applies to natural gas Various hybrid membrane fractions for the separation of hydrogen sulfide and carbon dioxide from feed streams Regarding the use of remote systems. For more information, see Hybrid membrane separation systems for acid gas The membrane system and at least one hydrogen sulfide membrane system are The resulting hydrogen sulfide-rich permeate can be sent directly to the vibrine. natural gas fibres, so that the flow is sufficient for use in the Claus sulfur plant. assembled in various configurations to provide acid gas separation and hydrogen sulfide enrichment from the Match.

Background of the invention Mixtures of hydrogen sulfide and other gases such as carbon dioxide and methane are present in many gas streams. be found. For example, a mixture of hydrogen sulfide, carbon dioxide, water and methane is found throughout the school. The US pipeline standard for natural gas is 2% carbon dioxide. and only 4 ppm hydrogen sulfide. Therefore, purification of gas mixtures or acid Hydrogen sulfide and carbon dioxide (also known as acid gases) are extracted from gas mixtures for the recovery of acid gases. ”) is required to be removed. It also purifies gaseous hydrocarbon streams. A sweetener that does not poison certain catalysts and meets normal Vibrine standards. To generate dry gas 1. f is necessary. Additionally, hydrogen sulfide can be Recovery as a source of sulfur is also highly desirable. That is, sour natural gas During the separation of hydrogen sulfide from a gas, sulfide water is removed without removing all of the carbon dioxide. It is desirable to selectively separate the elements. Usually separated hydrogen sulfide and carbon dioxide A portion of the element is fed to the Claus Sulfur Plant for conversion to elemental sulfur.

Typical natural gas processing plant flow sheets are shown in FIGS. 1 and 2. Figure 1 is , sour natural gas is fed to a gas/liquid separator 10 and the resulting gaseous product is Amine absorption or cryogenic fractionation device 12 to remove hydrogen sulfide and carbon dioxide from Shows the natural gas process sent to. Amine absorber 12 separates the components and sulfurizes them. Hydrogen to Claus sulfur plant 14, carbon dioxide to compressor 16, methane to dehydrate Supply to device 18. Claus sulfur plant 14 sends elements to storage facility 20 Produces sulfur and tail gas which is sent to scrubber 22. Dehydrated in dehydrator IB The recovered methane is sent to a nitrogen rejection device 24 where helium is recovered.

The methane is then compressed in compressor 26 and the helium is sent to purifier 28 .

Figure 2 shows other methods for carbon dioxide and hydrogen sulfide removal combined with acid gas concentration. Show the process. According to this process flow sheet, sour natural gas The separated acid gas is sent to the absorption or low-temperature fractionation device 30 and contains approximately 16% hydrogen sulfide. The remainder is essentially carbon dioxide. The separated acidic gas is purified by hydrogen sulfide. Acid gas concentrator 3 which is concentrated to approximately 60% before being supplied to Louth sulfur plant 34 Sent to 2. Claus Sulfur Plant 34 produces elemental sulfur and hydrogenated (36) , separated from residual hydrogen sulfide recycled to Claus Sulfur Plant 34 ( 38) Produces residual gas.

The traditional method for removing hydrogen sulfide and carbon dioxide from natural gas is amine absorption. Or use a cryogenic fractionation system. Used to remove acid gases from gas mixtures Some examples of absorption systems are disclosed in U.S. Pat. No. 3,594,985 [Ame en) et al.], published July 27, 1971; 27th issue 80.424 [Mirror ( Miller et al.], published March 21, 1978; and No. 3,664,091 Issue [Hegwer], published on May 23, 119725. There is.

Still others have proposed separation of acid gases from natural gas by absorption or by a combination of fractionators and membranes. U.S. Pat. No. 4,374,657 [Sche ], published on February 22, 11983, and No. 4.466.946 [ Godden, Jr. et al.], published on August 21, 119848 Schenclel et al. The residue is separated by low-temperature distillation, and then acidic gas is used to semipermeate the residue from the remaining hydrocarbons. Discloses a method of separation by passing through a membrane system. Ziendel Hakani The semipermeable membranes used are cellulose acetate, cellulose diacetate, and cellulose triacetate. , cellulose propionate, cellulose butyrate, cellulose cyanoethylate, Contains cellulose tacrylate, or mixtures thereof.

The Godden, Jr. et al. patent includes a process for treating a gas stream. = (a) selection of carbon dioxide from the gas stream across a uniquely permeable membrane in the permeation zone; A first portion of carbon dioxide is separated by selective permeation to form a carbon dioxide permeate stream and (b) further producing at least one hydrocarbon-enriched first stream; In the carbon oxide removal zone, the low-temperature fraction of the hydrocarbon enrichment first stream is separate the carbon dioxide to produce at least a carbon stream and a carbon dioxide stream; One aspect is included that includes:

Unfortunately, the use of amine absorption or cryogenic fractionation systems for acid gas removal is impractical. It is always energy inefficient (, expensive, bulky. US energy consumption is estimated at approximately 0.22 quads. moreover, Gas supply in the United States from large natural gas fields to small, low-quality, remote gas fields changes would require substantially smaller processing plants. Amine group gas treatment systems are economically and structurally viable for use in these small gas fields. It would be useless.

Until recently, the use of membrane technology for acid gas removal was limited for two main reasons: (1) 4pp hydrogen sulfide could not be separated sufficiently to reach an acceptable level of m; and (2 ) The composition of the acid gas contains a large amount of carbon dioxide and the Claus Sulfur Plant Feed Regulations It was not considered because it did not meet the criteria.

Various acid gas membranes are known that can separate both carbon dioxide and hydrogen sulfide from natural gas. It is being These membranes are described in U.S. Pat. No. 4,589,896 [Chan [Kerry (Kelly)], published April 21, 1987; No. 4,435.191 [Graph Graham], published March 6, 1984; and No. 4.857.07 No. 8 [Watler, published August 15, 1989, disclosed in ing. They are all referenced here.

Chen et al. spiral wound cellulose acetate type or polysulfone hollow Acid gas membranes, such as thread-type membranes, are disclosed. These membranes remove most of the carbon dioxide and and substantially all the hydrogen sulfide from the hydrocarbon residual gas. Then hydrogen sulfide is separated from carbon dioxide by a fractionation column containing an acid gas removal solvent.

Kelly describes various membranes that can separate carbon dioxide from hydrocarbons, i.e. Cellulose acetate, cellulose diacetate, cellulose triacetate, cellulose propionate cellulose, cellulose butyrate, cellulose cyanoethylate, cellulose methacrylate and mixtures thereof. Similarly, Graham A variety of polysulfone membranes are disclosed that are useful for the separation of carbon dioxide from carbon dioxide.

Watler for the separation of methane from acid gases and other hydrocarbons. comprises a microporous support coated with an ultrathin permselective layer of rubbery polymer. A multilayer film is disclosed.

All of the above membranes remove enough carbon dioxide to meet Claus sulfur plant requirements. Hydrogen sulfide cannot be separated. Only the patent by Chen et al. This step is suitable for use in small natural gas fields. Requires the use of fractionating columns, which is economically and structurally impractical.

Some attempts have been made in the US to remove hydrogen sulfide from natural gas using hydrogen sulfide-selective membranes. National Patent No. 3,819.808 [Ward et al.], June 119746 Published on the 25th and No. 4.824.443 [Matson et al.], 1 Shown during publication April 25, 19894. See also all of these patents here. be done.

Ward et al. proposed that an acidic gas, such as hydrogen sulfide, pass between sulfur in a water-soluble salt. An immobilized liquid membrane is disclosed that is transported based on dissolution and dissociation of hydrogen chloride.

Matson et al., species containing nitrogen, oxygen, phosphorus or sulfur atoms. Made of polymers that are compatible with and swellable with high boiling point, highly polar solvents of the The swollen liquid film opens an immobilized liquid film supported on or in the pores of another microporous support. It shows.

This membrane separates acid gases, i.e. carbon dioxide and hydrogen sulfide, from other gases and gas mixtures. Furthermore, hydrogen sulfide can be selectively removed before carbon dioxide. Carbon dioxide can be selectively removed prior to hydrogen.

Any of the permselective membrane systems described above is sufficient for use in a Claus sulfur plant. No method is provided for the separation of hydrogen sulfide-rich permeate streams from natural gas. The inventor is , removing acid gases from natural gas feed streams and converting hydrogen sulfide into the Claus Sulfur Process acid gas selective membranes and sulfur gases that can separate to sufficient levels for use in Develop unique combination or hybrid membrane systems that include both hydrohydride-selective membranes. Ta.

In addition, acid gas removal from acid gas or natural gas feed streams and hydrogen sulfide restoration Use of both hydrogen sulfide selective membranes and acid gas membranes in the separation of permeate streams The use is very cost effective. Such membranes can be used in miniaturized treatment plants or retrofitted can be used in absorption systems.

Additionally, membrane-based processes for natural gas sweetening provide additional energy for acid gas removal. high energy associated with amine absorption systems Overcome costs. The use of high selectivity, high flux membranes also results in the lowest methane losses Will. Additional advantages of such a process are: (1) low capital investment, (2) installation (3) easy operation; (4) low weight and space requirements; (5) low environmental impact. (6) highly adaptable membrane systems; and (7) no electrical power, water or air required for operation. It is something that cannot be done.

The present invention also provides a number of additional advantages that will become apparent as described below.

Summary of the invention Acid gas removal from natural gas, including hydrogen sulfide membrane assemblies and acid gas membrane assemblies. Hybrid membrane system for separating gases. Hybrid membrane system according to the invention The system preferably converts the separated hydrogen sulfide-rich permeate to elemental sulfur. The plant is used in conjunction with a device called a Claus sulfur plant.

Possibly a dehydration membrane assembly before the hydrocarbon gas is delivered to the pipeline. Can be installed in the system to remove water.

Each membrane assembly described above includes at least one membrane module. However, high If a separation factor is desired, two- and three-stage membrane modules with litinate recyclers are available. preferred.

Preferred membrane module designs include co-current membrane modules, counter-current membrane modules and This is an Adpantaged membrane module. Each membrane module has a suitable i.e. sulfided Contains hydrogen, acid gas or water, selective membranes. These membranes are spiral-wound layers, flat sheet membrane, hollow fiber membrane, plate and frame membrane or any other suitable Any suitable membrane arrangement can be used.

According to another aspect of the invention, a hybrid membrane system for separating acid gas from natural gas is provided. The stem also includes an acid gas membrane assembly, a first hydrogen sulfide membrane assembly, and a second hydrogen sulfide membrane assembly. A hydrogen sulfide membrane assembly may be included.

Another object of the invention is to: is supplied to the hydrogen sulfide membrane assembly where it is separated as hydrogen sulfide-rich permeate. What to do: Transfer natural gas litinate from the hydrogen sulfide membrane assembly to carbon dioxide. Rich permeate is separated from natural gas litinate, hydrocarbon-rich feeding the acid gas membrane assembly where the analyte is delivered to the pipeline: and and hydrogen sulfide-rich permeate to equipment capable of converting hydrogen sulfide to elemental sulfur. A method for separating acid gas from a natural gas feed stream comprising: this The method optionally removes hydrocarbon-rich lithinate from acid gas membrane assemblies. The dehydrated hydrocarbon-rich lithinate is supplied to the water membrane assembly through a pipeline. The water may be removed before being supplied to the inlet. .

Another method of separating acid gas from a natural gas feed stream according to the invention is: natural gas Hydrogen sulfide and carbon dioxide are removed from the natural gas feed stream by acid gas purification. The extracted hydrocarbon-rich lithinate is separated as mieate and sent to the pipeline. Supplying the acid gas permeate to the acid gas membrane assembly; Sulfide water separated from acid gas permeate as hydrogen sulfide-rich permeate Step of supplying to the membrane assembly: Hydrogen sulfide-rich permeate is added to sulfide water. supplying the element to a device capable of converting the element to elemental sulfur. Hydrocarbon-rich lithine The tate is optionally fed to the dehydration membrane assembly to remove the dehydrated hydrocarbon-rich Water can be removed before feeding the lithinate to the pipeline.

Yet another method of separating acid gases from a natural gas stream according to the present invention is: Hydrogen sulfide and carbon dioxide are acid gases from the natural gas feed stream. feeding the acid gas membrane assembly where it is separated as vermeate; Hydrogen sulfide absorbs acid gas permeate from the membrane assembly. The first hydrogen sulfide system is separated from the first hydrogen sulfide rich vermate. feeding the natural gas lithinate to the membrane assembly; hydrogen sulfide It is separated from suritinate as secondary hydrogen sulfide lithitpermeate, which is a hydrocarbon The rich lithinate is delivered to the second hydrogen sulfide membrane assembly which is sent to the pipeline. and supplying the first and second hydrogen sulfide rich permeates to the hydrogen sulfide. to a device capable of converting the sulfur into elemental sulfur. This method is , optionally dewatering the hydrocarbon-rich lithinate of the second hydrogen sulfide membrane assembly. feed the membrane assembly and deliver the dehydrated hydrocarbon litinate to the pipeline. The step of removing water may be included before dispensing.

Any of the foregoing systems or methods may optionally include membrane assembly glue tentate. at least one direct conversion unit capable of separating residual hydrogen sulfide from the Ru.

Other and further objects, advantages and features of the present invention are set forth in the following specification, with like parts being referred to by like reference numerals. BRIEF DESCRIPTION OF THE DRAWINGS FIG.

Brief description of the drawing Figure 1 shows a conventional natural gas processing plant flow sheet: Figure 2 shows amine absorption and Showing the acid gas concentration process flow sheet; Figure 3a is a schematic diagram of the countercurrent membrane module. Some of the tentate in Fig. 3b serves as a carrier gas for the permeate. Figure 30 is a schematic diagram of a countercurrent membrane module used in 1 is a schematic diagram of a countercurrent membrane module carried out of the module; Figure 3d is a schematic diagram of a co-current membrane module; Figure 3e is a diagram of an adapted or natural membrane module. Figure 4a is a schematic diagram of a two-stage membrane assembly according to the invention. Figure 4b is a schematic diagram of a three-stage membrane assembly according to the invention; Figure 5a is a diagram of a three-stage membrane assembly according to the invention; 1 is a schematic diagram of a combined hydrogen sulfide and acid gas membrane system according to one embodiment of the present invention: Figure 5b shows a combined hydrogen sulfide assembly according to another embodiment of the invention that also includes a dehydration membrane assembly. and an acid gas membrane system; FIG. 6a is a combination according to another embodiment of the invention. 1 is a schematic diagram of an acid gas and hydrogen sulfide membrane system; Figure 6b also includes a dehydration membrane assembly and direct conversion device located in the system. 2 is a schematic diagram of a combined acid gas and hydrogen sulfide membrane system according to another embodiment of the present invention. ; FIG. 7a shows an embodiment of the present invention including an acid gas membrane assembly and a hydrogen disulfide membrane assembly. 7b is a schematic diagram of a multiple membrane system according to yet another embodiment; FIG. assembly, hydrogen disulfide membrane assembly and dehydration membrane assembly. 2 is a schematic diagram of a multiple membrane system according to another embodiment.

Description of preferred embodiments The present invention provides sulfurized water with a membrane that has a high preference for hydrogen sulfide compared to carbon dioxide. Membrane assembly and high preference for acid gases compared to hydrocarbons and water provides a hybrid membrane system including an acid gas membrane assembly having a membrane with . Hybridization of hydrogen sulfide membrane assemblies and acid gas membrane assemblies is particularly For small plants and in the treatment of gases with high acid content, conventional absorption yields a system that exhibits better performance and lower construction costs than low-temperature and low-temperature plants.

It also operates the Claus Sulfur Plant, a system that converts hydrogen sulfide to elemental sulfur. stem, allowing sufficient concentration of hydrogen sulfide for use in.

The unique hybrid membrane system according to the present invention is best illustrated by reference to the accompanying drawings. Figure 5a shows a hydrogen sulfide membrane assembly 50 and an acid gas membrane assembly. A hybrid membrane system is shown to separate acid gases from natural gas containing Brie-52. vinegar. This hybrid membrane system preferably has a separated hydrogen sulfide rich permeate. A device 54 for converting mieto to elemental sulfur, a Claus sulfur plant, and Also used.

As shown in FIG. 5b, the dehydration membrane assembly 56 is optionally attached to a hydrocarbon in the system to remove water before supplying the rich tintate to the pipeline. Can be installed.

Each membrane assembly 50, 52 and 56 includes at least one membrane module.

As shown in Figures 4a and 4b, the lithinate recycling device is A three-stage membrane module is preferred if high separation factors are desired.

Figure 4a shows a membrane assembly with two membrane modules 60 and 62 mounted in series. - indicates. Modules 60 and 62 are connected by conduit 64 and compressor 66; The vermeate from module 60 is placed in the module under sufficient pressure to promote satisfactory separation. 62. The glue tentate from membrane module 62 is preferably It is recycled to module 60 via cycle conduit 68. concentrated perm The concentration of permeate is greater than the concentration of permeate exiting the first membrane module 60 via conduit 64. The high concentration exits the two-stage membrane assembly via conduit 70.

Figure 4b shows a membrane assembly with three membrane modules 76, 78 and 8o. Moji module 76 is connected to module 78 by permeate conduit 82 and compressor 84 and the vermeate from module 76 is sent to module 78 for additional separation. Sent. Glue tentate from module 78 is recycled into a recycle conduit for reprocessing. 86 and recycled to module 76. Similarly, module 78 Connected to the module 80 by a mieto conduit 88 and a compressor 90, the module Permeate from 78 is sent to module 8o for additional separation. Moju The glue tentate from the tube 80 is sent to the module for reprocessing via a recycling conduit 92. is recycled to 78. The concentrated permeate is provided to module 76. module 80 via conduit 94 at a much higher concentration than the original feed stream supplied. exit.

Preferred membrane models used for both hydrogen sulfide, acid gas and dehydration membrane modules Some of the Joule designs are shown in Figures 3a-3e. Figures 3a-3c are permeate is removed from the module in a direction opposite or opposite to the direction of the feed flow. i.e. , Figure 3a shows that an inert carrier gas such as nitrogen removes the vermeate from the module. This is a countercurrent membrane module supplied for discharge. Figure 3b modulates permeate. A portion of the lithinate is used to remove it from the tube. Countercurrent membrane shown in Figure 3c Permeate in the module is based on the difference in concentration within the permeate region. is removed.

Figure 3d shows permeate being removed from the module in the same direction as the feed stream.

Figure 3e shows an ad in which vermeate is mixed naturally or forced to average the concentration. A pantaged membrane module is shown.

The systems of Figures 5a and 5b contain natural gas containing methane, carbon dioxide, hydrogen sulfide and water. The sulfide stream contains hydrogen sulfide-rich vermeate containing hydrogen sulfide and carbon dioxide. It acts to be supplied to the hydrogen sulfide membrane assembly 50. Membrane assembly lip Tivermieto is produced in the Claus Sulfur Plant 54, where hydrogen sulfide is converted to elemental sulfur. supplied to The natural gas litinate from the hydrogen sulfide membrane assembly 50 is gas-rich permeates and hydrocarbons containing large amounts of methane and water. It is passed to acid gas membrane assembly 52 where tentate is produced. Hydrocarbon If the water concentration in the nociltentate meets pipeline specifications, the hydrocarbon Direct delivery of notitentate from the acid gas membrane assembly 52 to the pipeline I can do it. However, if the water concentration exceeds pipeline specifications, hydrocarbon The titritinate is sent to the dehydration membrane assembly 56 as shown in Figure 5b. so that a suitable hydrocarbon-rich feed can be sent to the pipeline. water should be removed from it.

Alternatively, the natural gas feed stream may begin with acid gases, i.e., carbon dioxide and sulfide. Hydrogen is separated from it as an acid gas, which is then passed through the hydrogen sulfide membrane assembly 50 (see Figure 6a).

Hydrogen sulfide membrane assembly 50 contains hydrogen sulfide-rich permeate from assembly 50. The sulfur can be sent to the Claus Sulfur Plant 54 for conversion to elemental sulfur. From the acid gas permeate generated by the acid gas membrane assembly 52, This produces a hydrogen sulfide-rich permeate with a substantially high hydrogen sulfide concentration. Figure 6b The hydrocarbon rich gas produced by the acid gas membrane assembly 52 is shown in FIG. If the ritinate contains a water concentration greater than the pipeline specification, the dehydration membrane assembly Bree 56 can be used. Optionally, direct conversion equipment 57.58 and 59 from the acid gas membrane assembly 52, glue tentate and sulfide water, respectively. Exhaust from glue tentate and Claus sulfur plant from membrane assembly 50 The amount of hydrogen sulfide contained within can be further reduced. Direct conversion of these The device typically removes residual hydrogen sulfide irreversibly by well-known polishing techniques. Including chemical scavenging.

According to another aspect of the invention shown in Figures 7a and 7b, acid gas from natural gas is The hybrid membrane system for separating acid gas also includes acid gas membrane assembly 100, includes a first hydrogen sulfide membrane assembly 102 and a second hydrogen sulfide membrane assembly 104 be able to. These systems include methane, carbon dioxide, hydrogen sulfide and water Natural gas produces acid gas permeates, i.e. hydrogen sulfide and carbon dioxide. 1 Supply to the acid gas membrane assembly 100 sent to the hydrogen sulfide membrane assembly 102 It acts as if it were supplied. The acid gas permeate is further processed by the first hydrogen sulfide membrane assembly. Separated in Brie, it also produces higher concentrations of hydrogen sulfide than acid gas permeates. produces hydrogen sulfide-rich permeate. Hydrogen sulfide rich vermeate is then fed to Claus Sulfur Plant 106 for conversion of hydrogen sulfide to elemental sulfur . The hydrocarbon-rich lithinate from acid gas membrane assembly 100, i.e. The methane, water and hydrogen sulfide are passed to and contained in the second hydrogen sulfide membrane assembly 104. Most of the residual hydrogen sulfide contained in the membrane assembly 104 is replaced by hydrocarbons originating from the membrane assembly 104. The rich lithinate is separated to meet pipeline specifications. moreover, Hydrocarbon-rich lithinate exiting the second hydrogen sulfide membrane assembly 104 drains water. Dehydrate hydrocarbon-rich lithinate if it is present in amounts exceeding pipeline specifications. It is desirable to send the water to a membrane assembly 108 to remove unwanted water therefrom. It would be nice.

Each membrane module preferably has the desired selectivity, i.e. hydrogen sulfide, acid gas or water. , including membranes with . These membranes include spiral wound layers, flat sheet membranes, and hollow fiber membranes. , plate-and-frame membrane or any other suitable membrane arrangement. Ru.

Hydrogen sulfide selective membrane Some examples of hydrogen sulfide selective membranes are gel polymer membranes, molten salt membranes, and rubber copolymer membranes. It is.

One example of a preferred gel copolymer membrane is U.S. Pat. No. 4,824,443 [Matson et al. (!1latson) et al.], published on April 25, 119894. is referred to here. This gel polymer membrane consists of (a) a microporous support and (b) a solvent. The medium has highly polar groups in its molecular structure, and the highly polar groups are nitrogen, oxygen, phosphorus, and and sulfur, and the solvent is at least 100°C. boiling point and about 7.5 to about 13. 5 (cat/cm’-atm)” dissolution parameter A small number of solvents (compatible with one solvent) selected from a variety of solvents, including A composite immobilized liquid membrane comprising a solvent-swellable polymer that can be swollen with water.

A molten salt hydrate membrane that can be used to separate hydrogen sulfide gas from a gaseous feed stream is a US patent. No. 4.780.114 [Quinn et al.], disclosed in Air Products & Chemicals (Air Products & Chemi) cals, Inc., Allentown, Penn5ylvania) Sold by.

Rubber copolymer membranes are disclosed in U.S. Pat. No. 4,857,078 [Watler ), published August 15, 1989, and is hereby incorporated by reference. it is Multilayer comprising a microporous support coated with an ultrathin permselective layer of rubbery polymer It is a membrane.

Acidic gas selective membrane The acidic gas permeable membrane is preferably a cellulose acetate membrane, a polyimide membrane, or a polysiloxane membrane. selected from the group consisting of a sun membrane and a pyrolone membrane. but, Many other polymeric membranes are also used for the separation of acid gases from natural gas feed streams. It is thought that it can be done.

Some examples of acid gas selective membranes are disclosed in U.S. Pat. No. 4,589,896 [Ch. en) Haka], issued May 20, 1986: U.S. Patent No. 4,659,343 [ Kelly), issued April 21, 1987, and U.S. Pat. No. 35.191 (Graham), published March 6, 1984, in It is shown. Reference is made to each of the aforementioned patents.

Exemplary polymer compositions suitable for use in acid gas membranes include polysulfone, polyester, - Tersulfone, styrene polymers and copolymers, polycarbonate, cells Loose polymer, polyamide, polyimide, polyether, polyarylene oxide Sid, polyurethane, polyester, polyacrylate, polysulfide, poly It can be chosen from olefins, polyvinyls and polyvinyl esters. in terpolymers, interpolymers containing repeating blocks of units corresponding to said polymers; Polymers, as well as grafted polymers and blends of the foregoing, are also suitable for use in membranes. Suitable.

Preferred membranes are cellulose esters such as cellulose acetate and cellulose diacetate. Loin, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose cellulose methacrylate and mixtures thereof.

Dehydration selective membrane One example of such a dehydration selective membrane is Bend Research's (Bend Re5ea) rch Inc.

Bend, Oregon).

Although certain embodiments according to the invention have been shown and described, they will be apparent to those skilled in the art. It should be clearly understood that Kana is subject to many changes. Therefore, it shows, It is not desired to be limited to the details described, but all variations that come within the scope of the claims are provided. It is intended to indicate changes and modifications.

Eight Procedural amendment

Claims (74)

[Claims] 1. hydrogen sulfide membrane assembly; and Acid gas membrane assembly A hybrid membrane system for separating acid gases from natural gas, including: 2. Claim 1, further comprising an apparatus for converting hydrogen sulfide to elemental sulfur. system. 3. The system of claim 1, further comprising a dehydration membrane assembly. 4. the hydrogen sulfide membrane assembly includes at least one hydrogen sulfide membrane module; The system of claim 1. 5. Hydrogen sulfide membrane modules are divided into co-current membrane modules, counter-current membrane modules, and add-on membrane modules. 5. The system of claim 4, wherein the system is selected from the group consisting of vanaged membrane modules. . 6. Hydrogen sulfide membrane modules include spiral wound membranes, flat sheet membranes, hollow fiber membranes, and a hydrogen sulfide selective membrane selected from the group consisting of plate and frame membranes. 6. The system of claim 5, comprising: 7. Hydrogen sulfide selective membranes are available from gel polymer membranes, molten salt membranes and rubber copolymer membranes. 7. The system of claim 6, wherein the system is selected from the group consisting of: 8. the acid gas membrane assembly includes at least one acid gas membrane module; The system of claim 1. 9. Acid gas membrane modules are divided into co-current membrane modules, counter-current membrane modules, and add-on membrane modules. 9. The system of claim 8, wherein the system is selected from the group consisting of vanaged membrane modules. . 10. Acid gas membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. , and an acid gas selective membrane selected from the group consisting of plate-and-frame membranes. 10. The system of claim 9, comprising: 11. Acidic gas selective membranes include cellulose acetate membranes, polyimide membranes, and polysiloxane membranes. 11. The system of claim 10, wherein the system is selected from the group consisting of a membrane, and a pyrolone membrane. 12. Claim wherein the dehydration membrane assembly comprises at least one dehydration membrane module. The system described in 3. 13. Dehydration membrane modules are divided into co-current membrane modules, counter-current membrane modules, and advance membrane modules. 13. The system of claim 12, wherein the system is selected from the group consisting of integrated membrane modules. . 14. Dehydration membrane modules include spiral wound membranes, flat sheet membranes, hollow fiber membranes, and a dehydration selective membrane selected from the group consisting of: 14. The system of claim 13. 15. 15. The system of claim 14, wherein the dehydration selective membrane is a polysiloxane membrane. 16. Acid gas membrane assembly; a first hydrogen sulfide membrane assembly; and second hydrogen sulfide membrane assembly; A hybrid membrane system for separating acid gases from natural gas, including: 17. Claim 16 further comprising an apparatus for converting hydrogen sulfide to elemental sulfur. The system described. 18. 17. The system of claim 16, further comprising a dehydration membrane assembly. 19. The first and second hydrogen sulfide membrane assemblies each contain at least one hydrogen sulfide membrane assembly. 17. The system of claim 16, comprising a bare membrane module. 20. Hydrogen sulfide membrane modules are divided into cocurrent membrane modules, countercurrent membrane modules, and a 20. The system of claim 19, wherein the system is selected from the group consisting of: Tem. 21. Hydrogen sulfide membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. and a hydrogen sulfide selective membrane selected from the group consisting of , and plate-and-frame membranes. 21. The system of claim 20, comprising: 22. Hydrogen sulfide selective membranes are gel polymer membranes, molten salt membranes and rubber copolymer membranes. 22. The system of claim 21, wherein the system is selected from the group consisting of: 23. the acid gas membrane assembly includes at least one acid gas membrane module 17. The system of claim 16. 24. Acid gas membrane modules are divided into co-current membrane modules, counter-current membrane modules, and a 24. The system of claim 23, wherein the system is selected from the group consisting of: Tem. 25. Acid gas membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. , and an acid gas selective membrane selected from the group consisting of plate-and-frame membranes. 25. The system of claim 24, comprising: 26. Acidic gas selective membranes include cellulose acetate membranes, polyimide membranes, and polysiloxane membranes. 26. The system of claim 25, wherein the system is selected from the group consisting of a membrane, and a pyrolone membrane. 27. Claim wherein the dehydration membrane assembly comprises at least one dehydration membrane module. 18. The system according to 18. 28. Dehydration membrane modules are divided into co-current membrane modules, counter-current membrane modules, and advance membrane modules. 28. The system of claim 27, wherein the system is selected from the group consisting of integrated membrane modules. . 29. Dehydration membrane modules include spiral wound membranes, flat sheet membranes, hollow fiber membranes, and a dehydration selective membrane selected from the group consisting of: 29. The system of claim 28. 30. 30. The system of claim 29, wherein the dehydration selective membrane is a polysiloxane membrane. 31. A method for separating acid gas from a natural gas feed stream, the method comprising: The feed stream is converted into a hydrogen sulfide-rich permiacetate by hydrogen sulfide from the natural gas feed stream. feeding a hydrogen sulfide membrane assembly where it is separated as a Carbon dioxide absorbs the natural gas retentate from the hydrogen sulfide membrane assembly. Separated from natural gas retentate, hydrocarbon-rich retentate is produced in pipelines. and supplying said hydrogen sulfide rich acid gas membrane assembly to an acid gas membrane assembly; feeding permeate to a device capable of converting said hydrogen sulfide to elemental sulfur; method including. 32. Furthermore, the hydrocarbon-rich retentate of the acid gas membrane assembly is dehydrated. to remove water from the hydrocarbon-rich retentate before sending it to the pipeline. 32. The method of claim 31, comprising feeding a dehydration membrane assembly to a dehydration membrane assembly. 33. the hydrogen sulfide membrane assembly includes at least one hydrogen sulfide membrane module 32. The method of claim 31. 34. Hydrogen sulfide membrane modules are divided into cocurrent membrane modules, countercurrent membrane modules, and a 34. The method of claim 33, wherein the method is selected from the group consisting of: . 35. Hydrogen sulfide membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. and a hydrogen sulfide selective membrane selected from the group consisting of , and plate-and-frame membranes. 35. The method of claim 34, comprising: 36. Hydrogen sulfide selective membranes are gel polymer membranes, molten salt membranes and rubber copolymer membranes. 36. The method of claim 35, wherein the method is selected from the group consisting of: 37. the acid gas membrane assembly includes at least one acid gas membrane module 32. The method of claim 31. 38. Acid gas membrane modules are divided into co-current membrane modules, counter-current membrane modules, and a 38. The method of claim 37, wherein the method is selected from the group consisting of: . 39. Acid gas membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. , and an acid gas selective membrane selected from the group consisting of plate-and-frame membranes. 39. The method of claim 38, comprising: 40. Acidic gas selective membranes include cellulose acetate membranes, polyimide membranes, and polysiloxane membranes. 40. The method of claim 39, wherein the method is selected from the group consisting of a membrane, and a pyrolone membrane. 41. Claim wherein the dehydration membrane assembly comprises at least one dehydration membrane module. The method described in 32. 42. Dehydration membrane modules are divided into co-current membrane modules, counter-current membrane modules, and advance membrane modules. 42. The method of claim 41, wherein the method is selected from the group consisting of integrated membrane modules. 43. Dehydration membrane modules include spiral wound membranes, flat sheet membranes, hollow fiber membranes, and a dehydration selective membrane selected from the group consisting of: 43. The method of claim 42. 44. 44. The method of claim 43, wherein the dehydration selective membrane is a polysiloxane membrane. 45. 1. A method for separating acid gas from a natural gas feed stream, the method comprising: The feed stream is configured such that hydrogen sulfide and carbon dioxide are removed from the natural gas feed stream as an acid gas. The hydrocarbon-rich retentate is separated as permeate and sent to the pipeline. supplying the acid gas permeate to an acid gas membrane assembly; Hydrogen sulfide is separated from the acid gas permeate as hydrogen sulfide-rich permeate. supplying a hydrogen sulfide membrane assembly to be separated; and The hydrogen sulfide-rich permeate stream is supplied with an equipment capable of converting the hydrogen sulfide to elemental sulfur. supplying the method including. 46. Furthermore, the hydrocarbon-rich retentate of the acid gas membrane assembly is dehydrated. water is removed from the hydrocarbon-rich retentate before it is fed to the pipeline. 46. The method of claim 45, comprising feeding a dehydration membrane assembly for dewatering. 47. the hydrogen sulfide membrane assembly includes at least one hydrogen sulfide membrane module 46. The method of claim 45. 48. Hydrogen sulfide membrane modules are divided into cocurrent membrane modules, countercurrent membrane modules, and a 48. The method of claim 47, wherein the method is selected from the group consisting of: . 49. Hydrogen sulfide membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. and a hydrogen sulfide selective membrane selected from the group consisting of , and plate-and-frame membranes. 49. The method of claim 48, comprising: 50. Hydrogen sulfide selective membranes are gel polymer membranes, molten salt membranes and rubber copolymer membranes. 50. The method of claim 49, wherein the method is selected from the group consisting of: 51. the acid gas membrane assembly includes at least one acid gas membrane module 46. The method of claim 45. 52. Acid gas membrane modules are divided into co-current membrane modules, counter-current membrane modules, and a 52. The method of claim 51, wherein the method is selected from the group consisting of: . 53. Acid gas membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. , and an acid gas selective membrane selected from the group consisting of plate-and-frame membranes. 53. The method of claim 52, comprising: 54. Acidic gas selective membranes include cellulose acetate membranes, polyimide membranes, and polysiloxane membranes. 54. The method of claim 53, wherein the method is selected from the group consisting of a membrane, and a pyrolone membrane. 55. Claim wherein the dehydration membrane assembly comprises at least one dehydration membrane module. 46. 56. Dehydration membrane modules are divided into co-current membrane modules, counter-current membrane modules, and advance membrane modules. 56. The method of claim 55, wherein the method is selected from the group consisting of integrated membrane modules. 57. Dehydration membrane modules include spiral wound membranes, flat sheet membranes, hollow fiber membranes, and a dehydration selective membrane selected from the group consisting of: 57. The method of claim 56. 58. 58. The method of claim 57, wherein the dehydration selective membrane is a polysiloxane membrane. 59. 1. A method for separating acid gas from a natural gas feed stream, the method comprising: The feed stream is configured such that hydrogen sulfide and carbon dioxide are removed from the natural gas feed stream as an acid gas. feeding to an acid gas membrane assembly where it is separated as permeate; The acid gas permeate from the acid gas membrane assembly is pretreated with hydrogen sulfide. It is separated from the acidic gas permeate as primary hydrogen sulfide-rich permeate. supplying natural gas retentate to the first hydrogen sulfide system membrane assembly; , hydrogen sulfide is converted from the natural gas retentate to secondary hydrogen sulfide-rich permeate. The second sulfide is separated and the hydrocarbon-rich retentate is sent to the pipeline. supplying the first and second hydrogen sulfide rich permiers to a hydrogen membrane assembly; feeding said hydrogen sulfide to an apparatus capable of converting said hydrogen sulfide to elemental sulfur; method including. 60. Furthermore, the hydrocarbon-rich retentate of the second hydrogen sulfide membrane assembly is Remove water from dehydrated hydrocarbon-rich retentate before feeding it to the pipeline 60. The method of claim 59, comprising feeding a dehydration membrane assembly to . 61. the hydrogen sulfide membrane assembly includes at least one hydrogen sulfide membrane module 60. The method of claim 59. 62. Hydrogen sulfide membrane modules are divided into cocurrent membrane modules, countercurrent membrane modules, and a 62. The method of claim 61, wherein the method is selected from the group consisting of: . 63. Hydrogen sulfide membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. and a hydrogen sulfide selective membrane selected from the group consisting of , and plate-and-frame membranes. 63. The method of claim 62, comprising: 64. Hydrogen sulfide selective membranes are gel polymer membranes, molten salt membranes and rubber copolymer membranes. 64. The method of claim 63, wherein the method is selected from the group consisting of: 65. the acid gas membrane assembly includes at least one acid gas membrane module 60. The method of claim 59. 66. Acid gas membrane modules are divided into co-current membrane modules, counter-current membrane modules, and a 66. The method of claim 65, wherein the method is selected from the group consisting of: . 67. Acid gas membrane modules include spiral wound membranes, flat sheet membranes, and hollow fiber membranes. , and an acid gas selective membrane selected from the group consisting of plate-and-frame membranes. 67. The method of claim 66, comprising: 68. Acidic gas selective membranes include cellulose acetate membranes, polyimide membranes, and polysiloxane membranes. 68. The method of claim 67, wherein the method is selected from the group consisting of a membrane, and a pyrolone membrane. 69. Claim wherein the dehydration membrane assembly comprises at least one dehydration membrane module. 60. 70. Dehydration membrane modules are divided into co-current membrane modules, counter-current membrane modules, and advance membrane modules. 70. The method of claim 69, wherein the method is selected from the group consisting of integrated membrane modules. 71. Dehydration membrane modules include spiral wound membranes, flat sheet membranes, hollow fiber membranes, and a dehydration selective membrane selected from the group consisting of: 71. The method of claim 70. 72. 72. The method of claim 71, wherein the dehydration selective membrane is a polysiloxane membrane. 73. Residual hydrogen sulfide is removed by direct conversion from retentate in any membrane assembly. 60. A method according to any one of claims 31, 45 or 59, wherein the method is separated. 74. Additionally, residual hydrogen sulfide can be separated from retentate in any membrane assembly. 17. According to any one of claims 1 or 16, comprising at least one direct conversion device capable of Method described.