Method and apparatus for removing carbon monoxide from an ethylene stream

Abstract

A process and apparatus for separating carbon monoxide from ethylene. The ethylene can be produced from a bio-based alcohol. The separation utilizes a fractionation column that produces a carbon monoxide-lean ethylene stream and an overhead stream comprising carbon monoxide and ethylene. Ethylene from the overhead stream can be recovered in an absorption zone with an absorption liquid. Oxygenate can be removed from the carbon monoxide-lean ethylene stream with an oxygenate fractionation zone.

Description

Related applications

[0001] This application claims the benefit of U.S. non-provisional patent application No. 18 / 919,072, filed October 17, 2024, which claims the benefit of U.S. provisional patent application sequence No. 63 / 611,445, filed December 18, 2023, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] The present invention relates generally to methods and apparatus for separating carbon monoxide from ethylene feed streams, and more particularly to removing carbon monoxide from ethylene feed streams generated during jet fuel production. Background Technology

[0003] With increasing global demand for fuels, the production of fuels from sources other than crude oil and the blending of components from sources other than crude oil are gaining increasing attention. These sources are often referred to as biorenewable sources and include, but are not limited to, vegetable oils such as corn oil, rapeseed oil, low-erucic acid rapeseed oil, and soybean oil; microbial oils such as algal oil; animal fats such as inedible tallow; fish oil; and various waste streams such as yellow and brown greases and sewage sludge. A common characteristic of these sources is that they consist of triglycerides and free fatty acids (FFAs). Both triglycerides and FFAs contain aliphatic carbon chains with approximately 8 to approximately 24 carbon atoms. The aliphatic carbon chains in triglycerides or FFAs can be fully saturated or mono, di, or polyunsaturated.

[0004] One exemplary method is the production of sustainable aviation fuel (SAF) from biorenewable sources, such as biorenewably derived ethanol. The conversion of ethanol feedstock to SAF typically involves four chemical processing steps: dehydration, oligomerization, hydrogenation, and fractionation. In such a processing scheme, carbon monoxide can negatively impact oligomerization. Therefore, it may be desirable to separate carbon monoxide from ethylene prior to the oligomerization step.

[0005] One technique for removing carbon monoxide impurities from ethylene is to pass the ethylene through a bed of solid adsorbent particles. The adsorbent material selectively captures carbon monoxide while allowing ethylene molecules to pass through unimpeded.

[0006] More methods are needed to separate carbon monoxide from ethylene. Summary of the Invention

[0007] The inventors have discovered a new method and apparatus for separating carbon monoxide from ethylene.

[0008] The disclosed invention applies the concept of fractionation under high pressure and low temperature to separate carbon monoxide from ethylene. In the method of the invention, the ethylene process feed stream is designed to use flash evaporation and automatic refrigeration as important sources of cooling, which provides a more efficient method.

[0009] Furthermore, this invention reduces ethylene loss by using an absorption zone of the absorbent liquid. The absorbent liquid can be from an existing process slip within the oligomerization process.

[0010] The method of this invention provides a reduction of carbon monoxide in ethylene to low ppm levels (approximately 5 vppm to 50 vppm). Simultaneously, ethylene loss due to carbon monoxide removal treatment can be minimized (<0.01%).

[0011] It has been surprisingly found that cold fractionation of ethylene and carbon monoxide provides an efficient method. Generally, cryogenic purification of ethylene at extremely cold temperatures has high operating costs. Due to these high costs, it is considered undesirable to incorporate into SAF production processes. Furthermore, such purification of ethylene is considered to increase the carbon intensity of SAF production and make it less sustainable. The inventors have discovered other aspects.

[0012] Therefore, the present invention is characterized in that, in at least one aspect, a method for separating carbon monoxide from ethylene by: cooling an ethylene stream with a refrigerant stream in a cooling zone; separating the ethylene stream into a liquid stream containing ethylene and an overhead stream containing carbon monoxide and ethylene in a fractionation zone including a fractionation tower; separating the overhead stream into a liquid portion and a gaseous portion in a container, wherein the gaseous portion contains carbon monoxide and ethylene; and absorbing ethylene from the gaseous portion with an absorbent liquid stream in an absorption zone to provide an enriched absorbent liquid containing an increased level of ethylene and a vapor of ethylene-lean containing carbon monoxide.

[0013] The method may also include reboiling the stream from the fractionation tower with the ethylene stream before cooling the ethylene stream in the cooling zone.

[0014] The method may include heating the liquid stream from the fractionation tower with the ethylene stream before cooling the ethylene stream in the cooling zone.

[0015] The method may include cooling the overhead stream with a refrigerant stream in a cooling zone before separating the overhead stream in a container.

[0016] Methods may include subcooling the refrigerant stream by transferring heat from the refrigerant stream to a portion of the liquid stream from the fractionation column.

[0017] The method may also include subcooling the refrigerant stream by transferring heat from the refrigerant stream to the gas portion from the container.

[0018] The absorbent liquid stream can be a hydrocarbon stream. The hydrocarbon stream can be an oligomer effluent. The enriched absorbent liquid can be reboiled.

[0019] The ethylene feed stream can be part of the dehydrated effluent.

[0020] The ethylene feed stream can have a pressure between 3,447 kPa and 4,137 kPa (500 psi (g) to 600 psi (g)), and the liquid feed stream can have a pressure between 2,413 kPa and 3,103 kPa (350 psi (g) to 500 psi (g)).

[0021] The method may include recovering power from the pressure reduction of ethylene-poor vapor using an expansion device.

[0022] The method may include cooling the process stream with a liquid stream.

[0023] The method may include separating a liquid ethylene stream into a liquid stream containing oxygenated compounds and an oxygenated compound fractionation zone overhead stream in an oxygenated compound fractionation zone, including a fractionation column; and separating the oxygenated compound fractionation zone overhead stream into a liquid portion and a gaseous portion in a vessel, wherein the gaseous portion contains ethylene and carbon dioxide. The method may also include reboiling the stream from the fractionation column in the oxygenated compound fractionation zone with a hot process stream. The method may further include cooling the oxygenated compound fractionation zone overhead stream with a refrigerant stream in a cooling zone before separating the overhead stream in the vessel.

[0024] In general, the present invention may also be characterized by providing a method for producing spray-range hydrocarbons from bio-based alcohols by: dehydrating a bio-based alcohol stream in a dehydration zone comprising a reactor having a catalyst and operating under conditions providing a dehydrated effluent containing ethylene and carbon monoxide; separating carbon monoxide from ethylene in a fractionation zone from a feed stream containing a portion of the dehydrated effluent, the fractionation zone providing a bottom stream containing a carbon monoxide-lean ethylene stream and an overhead stream containing carbon monoxide and ethylene; and using an absorbent liquid stream in an absorption zone. Ethylene is absorbed from a portion of the overhead feed stream to provide an enriched absorbent liquid feed stream containing increased levels of ethylene and a carbon monoxide-lean ethylene vapor feed stream; the carbon monoxide-lean liquid ethylene feed stream is oligomerized in an oligomerization zone comprising a reactor with a catalyst and operating under conditions for providing oligomerized effluent; the oligomerized effluent is hydrogenated in a hydrogenation zone comprising a hydrogenation reactor with a catalyst and operating under conditions for providing hydrogenated effluent; and the hydrogenated effluent is separated into one or more hydrocarbon feed streams containing jet fuel hydrocarbon vapor.

[0025] The liquid effluent can be an oligomer effluent.

[0026] The method may include separating the overhead stream into a liquid portion and a gaseous portion in a container, wherein the gaseous portion includes the portion of the overhead stream that absorbs ethylene in an absorption zone; or cooling the overhead stream with a refrigerant stream in a cooling zone before separating the overhead stream; or both of the above.

[0027] The method may include separating oxygenated compounds from the carbon-leaved ethylene stream in an oxygenated compound fractionation zone, including a fractionation tower, before oligomerizing the carbon-leaved ethylene stream into a liquid stream containing oxygenated compounds and an oxygenated compound fractionation zone overhead stream.

[0028] Further aspects, embodiments, and details of the invention (all of which may be combined in any way) are set forth in the following detailed description of the invention. Attached Figure Description

[0029] One or more exemplary embodiments of the present invention will now be described with reference to the following accompanying drawings, wherein:

[0030] Figure 1 A process flow diagram according to one or more embodiments of the present invention is shown; and,

[0031] Figure 2 A process flow diagram of a fractionation zone according to one or more embodiments of the present invention is shown.

[0032] Those skilled in the art should recognize and understand that various other components, such as valves, pumps, filters, coolers, etc., are not shown in the accompanying drawings because it is believed that their specific details are entirely within the knowledge of those skilled in the art and their description is not necessary for the implementation or understanding of the embodiments of the present invention. Detailed Implementation

[0033] As described above, methods and apparatus for separating carbon monoxide from ethylene have been invented. The method of the present invention separates carbon monoxide from bulk ethylene via cold fractionation (low temperature, high pressure). Furthermore, the method of the present invention minimizes ethylene loss through selective recovery using a sponge absorber system. The present invention also allows for efficient and effective thermal integration with process and utility systems. While these methods have the highest efficiency in converting feedstocks from alkanols, thereby allowing the production of jet fuel from renewable sources, this is not intended to limit the application of the methods of the present invention.

[0034] In view of these general principles, one or more embodiments of the invention will be described in accordance with the following description, which is not intended to be limiting.

[0035] refer to Figure 1The bio-based alcohol stream 10 is then fed into the first reaction zone 12. The bio-based alcohol stream 10 is preferably a bio-based ethanol stream. Therefore, the following detailed description will be based on an embodiment where the feed stream 10 contains a bio-based ethanol stream; however, this is merely illustrative.

[0036] Additionally, "bio-based" refers to organic materials whose carbon originates from carbon dioxide present in the atmosphere and has been fixed in recent (approximately several centuries) using solar energy (photosynthesis). On land, this carbon dioxide is captured or fixed by plant life (e.g., crops or forestry materials). In the ocean, carbon dioxide is captured or fixed by photosynthetic bacteria or phytoplankton. For example, bio-based materials have a carbon content greater than zero. 14 C / 12 C isotope ratio. Conversely, fossil-based materials have zero C isotope ratio. 14 C / 12 C isotope ratio. The term “renewable” for compounds such as alcohols or hydrocarbons (olefins, dienes, polymers, etc.) also refers to compounds prepared from biomass using thermochemical methods (e.g., Fischer-Tropsch catalysts), biocatalysts (e.g., fermentation) or other methods, as described herein.

[0037] Biomass fermentation products typically include lower isoparaffinols, such as C2 to C8 isoparaffinols obtained, for example, by contacting biomass with a biocatalyst that promotes the conversion (through fermentation) of biomass into isoparaffinols. The biomass feedstock used in this fermentation process can be any suitable fermentable feedstock known in the art, such as fermentable sugars derived from crops (including sugarcane, corn, etc.). Suitable fermentable biomass feedstocks can also be prepared by hydrolyzing biomass, such as lignocellulosic biomass (e.g., wood, corn stalks, switchgrass, herbiage plants, marine biomass, etc.) to form fermentable sugars.

[0038] exist Figure 1 In the first reaction zone 12, the dehydration zone includes a reactor with a catalyst and operates under conditions that provide a dehydrated effluent 14, which includes ethylene and carbon monoxide, and may also include hydrogen, carbon dioxide, methane, ethane, propane, propylene, butane, butene, pentane, pentene and oxygen-containing compounds such as diethyl ether, diethoxyethane and ethyl acetate.

[0039] Suitable catalysts may include alumina, modified alumina, aluminosilicates, modified aluminosilicates, or other catalysts known in the art. The reactor can be operated at temperatures from 200°C to 500°C (392°F to 932°F). In some embodiments, the dehydration reactor can be operated at pressures from 0 kPa to 8,300 kPa (0 psi (g) to 1,204 psi (g)). In some embodiments, the dehydration reactor can be operated at pressures from 0 kPa to 3,500 kPa (0 psi (g) to 508 psi (g)). In addition to the bio-based alcohol feed stream, an inert gas such as nitrogen or vapor may be introduced into the first reaction zone 12.

[0040] As noted above, the presence of carbon monoxide in the dehydrated effluent 14 may be undesirable for downstream processes. Therefore, in the method of the present invention, the dehydrated effluent 14, or a portion thereof, forms the feed stream for fractionation zone 16. Fractionation zone 16 is described in more detail below. However, typically, fractionation zone 16 includes a fractionation column and provides a carbon monoxide-lean ethylene feed stream 22 and a carbon monoxide-lean ethylene vapor feed stream 20, which contain the majority of the carbon monoxide from the dehydrated effluent 14.

[0041] The carbon monoxide-poor ethylene feed stream 22 is passed to the oligomerization zone 24, which includes a reactor with a catalyst and operates under conditions that provide oligomer effluent 26.

[0042] In oligomerization zone 24, ethylene is converted into a mixture of heavier-boiling hydrocarbons, including those in the spray range, by reacting olefins with a catalyst under appropriate conditions via oligomerization. For example, oligomerization zone 24 can be operated, but is not limited to, at a temperature of about 100°C to about 300°C (212°F to 572°F) and a pressure of about 689 kPa to about 6,895 kPa (100 psi (g) to 1,000 psi (g)).

[0043] The oligomerization catalyst in oligomerization zone 24 is not limited to any particular catalyst and may include one or more biorenewable C2 to C8 olefins in an olefin feed stream suitable for catalyzing the conversion of C2 to C8 olefins with higher boiling points. 5+ Any catalyst for the oligomer of hydrocarbon olefins, which has a higher boiling point (C) 5+ Hydrocarbons include those within the injection range. The oligomerization catalyst can be any such catalyst known now or in the future. An exemplary oligomerization catalyst is described in U.S. Patent Publication No. 2023 / 0313048.

[0044] like Figure 1 As shown, oligomer effluent 26 from oligomerization zone 24 can be transferred to hydrogenation zone 28, which has a hydrogenation reactor with a catalyst and operates under conditions that provide hydrogenated effluent 30.

[0045] Hydrogenation is typically carried out using conventional hydrogenation or hydrotreating catalysts, which may include metal catalysts containing, for example, palladium, rhodium, nickel, ruthenium, platinum, rhenium, cobalt, molybdenum, or combinations thereof, and their supported forms. The catalyst support can be any solid, inert material, including but not limited to oxides such as silica, alumina, titanium dioxide, calcium carbonate, barium sulfate, and carbon. The catalyst support can be in powder, granule, pellet, or other form. Hydrogenation is suitably carried out at temperatures between 38°C and 260°C (100°F to 500°F) and pressures between about 689 kPa and about 6,895 kPa (100 psi (g) to 1,000 psi (g)). Other process conditions known to those skilled in the art may be utilized.

[0046] The hydrogenated effluent 30 from hydrogenation zone 28 will consist substantially of saturated hydrocarbons (i.e., alkanes). The hydrogenated effluent 30 may be fed to separation zone 32 having one or more towers constructed and operated to separate the hydrogenated effluent 30 into one or more hydrocarbon streams 34, 36, 38, one of which is jet fuel hydrocarbon vapor.

[0047] As used herein, the terms "jet-range hydrocarbons," "jet-range alkanes," "jet-range fuels," or "jet fuels" can include hydrocarbons with a boiling point at atmospheric pressure ranging from about 130°C to about 300°C (266℉ to 572℉), preferably from 150°C to 260°C (302℉ to 500℉). Additionally, as used herein, the terms "jet-range hydrocarbons," "jet-range alkanes," "jet-range fuels," or "jet fuels" refer to hydrocarbons primarily composed of C8 to C94 hydrocarbons. 16 A mixture of hydrocarbons with a freezing point of about -40°C (-40°F) or about -47°C (-52.6°F).

[0048] Go to Figure 2 As discussed above, the present invention utilizes fractionation zone 16 to separate carbon monoxide and ethylene in ethylene feed stream 50. Ethylene feed stream 50 comprises a portion of 14 ( Figure 1 Although not described in this way, the ethylene feed stream 50 can first be compressed in various compressors, and in 12 ( Figure 1 The ethylene feed stream 50 is dried in the drying section to remove water before fractionation. The pressure of the ethylene feed stream 50 may be between 3,447 kPa and 4,137 kPa (500 psi (g) to 600 psi (g)) or about 3,758 kPa (545 psi (g)).

[0049] To remove heat from the ethylene feed stream 50, it can first be passed to a reboiler 52 to reboil the stream from the fractionation column 54 in the fractionation zone 16. The cooled ethylene feed stream 53 can then be passed from the reboiler 52 to a condenser 56 to transfer heat to the carbon monoxide-lean ethylene stream 22 from the fractionation column 54. Furthermore, the cooled condensed ethylene feed stream 57 can be cooled in a cooling zone 58 that receives the refrigerant stream 61 from the refrigeration unit 62. After passing through the cooling zone 58, the ethylene feed 59, with a temperature between, for example, -26°C and -1°C (-15℉ to 30℉), can be passed to the fractionation column 54. In the fractionation column 54, the components of the ethylene feed stream 50 will be separated into the carbon monoxide-lean ethylene stream 22 and the overhead stream 64, which includes both carbon monoxide and ethylene.

[0050] As will be understood, the carbon monoxide-lean ethylene feed 22 will primarily consist of ethylene and may include smaller portions of carbon dioxide, methane, ethane, propane, propylene, butane, butene, pentane, pentene, and oxygen-containing compounds (diethyl ether, diethoxyethane, and ethyl acetate). The carbon monoxide-lean ethylene feed 22 is a liquid and has a pressure between 2,413 kPa and 3,447 kPa (350 psi (g) to 500 psi (g)), for example, about 3,103 kPa (450 psi (g)) and a temperature between -18°C and 10°C (0°F to 50°F). Additionally, in addition to carbon monoxide and ethylene, the overhead feed 64 may also include hydrogen and methane. Since the overhead feed 64 includes ethylene, it is desirable to recover ethylene. Therefore, the invention contemplates an absorption zone 66.

[0051] like Figure 2 As depicted, the overhead stream 64 can be cooled in a cooling zone 68 before being conveyed to the absorption zone 66. This cooling zone receives the refrigerant stream 63 from the refrigerant unit 62 before it is conveyed to the separation vessel 72. In the separation vessel 72, the components of the overhead stream 64 are separated into a liquid portion 74 and a gaseous portion 76. The liquid portion 74, primarily composed of ethylene, can be pumped back to the fractionation column 54. The gaseous portion 76 will include carbon monoxide and ethylene, which is recovered in the absorption zone 66.

[0052] Before being transferred to the absorption zone 66, the gas stream 76 can be used to subcool the refrigerant stream 65 by transferring heat from the refrigerant stream 65 to the gas stream 76 in the cooling zone 97. The gas stream 76, with a temperature between -1°C and 93°C (30°F to 200°F), can be transferred to the absorber container 78, which also receives the absorbent liquid stream 80.

[0053] Gas stream 76 is fed into the lower portion of container 78, and absorbent stream 80 is fed into the upper portion of container 78. As the liquid flows downwards and the vapor flows upwards within container 78, ethylene in the vapor is absorbed by the liquid. Therefore, absorption zone 66 provides enriched absorbent liquid 82 containing increased levels of ethylene and ethylene-lean vapor 84 containing carbon monoxide. The ethylene-lean vapor 84 will contain most of the carbon monoxide separated from the ethylene feed stream 50. The ethylene-lean vapor 84 can be used as fuel gas, for example, in hydrogenation zone 28 (see...). Figure 1 ).

[0054] The absorbent liquid 80 should have a high affinity for ethylene and a low affinity for carbon monoxide. Therefore, the absorbent liquid 80 can be a hydrocarbon feed stream. For example, the absorbent liquid is expected to be an oligomer effluent, and preferably a first- or second-stage oligomer effluent stream, so that the enriched absorbent liquid 82 is returned to the oligomerization zone 24 to increase the yield of SAF. To enhance the repulsion of carbon monoxide in the enriched absorbent liquid, the enriched absorbent liquid can be reboiled with a hot feed stream 86.

[0055] Returning to fractionation column 54, the carbon monoxide-lean ethylene feed stream 22, or a portion thereof, can be used to subcool the refrigerant feed stream 67 by transferring heat from the refrigerant feed stream 67 to the carbon monoxide-lean ethylene feed stream 22 in heat exchange zone 88. Additionally, as described above, the carbon monoxide-lean ethylene feed stream 22 can be transferred to condenser 56. Further, it is anticipated that the carbon monoxide-lean ethylene feed stream 22 can be used to cool any other process feed streams. For example, the carbon monoxide-lean ethylene feed stream 22 can be used to cool the feed stream in the dryer section of dehydration zone 12. This is merely one anticipated example, and other feed streams can be cooled by the carbon monoxide-lean ethylene feed stream 22.

[0056] The carbon monoxide-lean ethylene feed stream 22 has a reduced carbon monoxide level and can therefore be returned to the compression zone as described above. Figure 1 Further processing as discussed above. However, as noted above, the carbon monoxide-lean ethylene stream 22 may also contain oxygen-containing compounds. Therefore, in some cases, it may be desirable to remove these oxygen-containing compounds. Furthermore, the conditions of the carbon monoxide-lean ethylene stream 22 are ideal for the removal of oxygen-containing compounds. Therefore, it is possible to... Figure 2 The depiction provides oxygen-containing compound fractionation zone 90.

[0057] The oxygen-containing compound fractionation zone 90 includes a column 92 that receives a carbon monoxide-lean ethylene feed stream 22, which operates under conditions that separate a liquid feed stream 94 containing oxygen-containing compounds and an oxygen-containing compound fractionation column overhead stream 96 containing ethylene. Column 92 can be reboiled with steam or a hot process feed stream 98.

[0058] The overhead feed stream 96 of the oxygen-containing fractionation column can be cooled with refrigerant stream 60 and then transferred to vessel 100. In vessel 100, the components are separated into a liquid portion 102 and a gaseous portion 104. The liquid portion can be pumped back to the oxygen-containing fractionation column 92, and the gaseous portion includes ethylene and, for example, carbon dioxide. Heat can be transferred from the feed stream 106 from refrigerant unit 62 to the gaseous portion 104. The gaseous portion 104 is also a carbon monoxide-lean ethylene feed stream 110, having a pressure between 2,413 kPa and 3,447 kPa (350 psi (g) to 500 psi (g)) and a temperature between -7°C and 66°C (20°F to 150°F), which can be returned to the compression zone for further processing as discussed above.

[0059] Generally speaking, this invention provides an effective and efficient method and apparatus for removing carbon monoxide from ethylene. To increase power recovery, it is conceivable to use an expansion device (such as a turbine) instead of a valve to recover power from the associated pressure drop.

[0060] The systems and devices described herein may include a controller 200 or a computing device including processing and memory storing computer-executable instructions for implementing the processes described herein. The processing unit may include any suitable device configured to cause a series of steps to be performed to implement the method, such that the instructions, when executed by a computing device or other programmable means, cause the functions / actions / steps specified in the methods described herein to be performed. The processing unit may include, for example, any type of general-purpose microprocessor or microcontroller, digital signal processing (DSP) processor, central processing unit (CPU), integrated circuit, field-programmable gate array (FPGA), reconfigurable processor, other suitable programmable or programmable logic circuitry, or any combination thereof.

[0061] Memory can be any suitable known or other machine-readable storage medium. Memory can include non-transitory computer-readable storage media, such as, but not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any suitable combination thereof. Memory can include any suitable combination of computer memories, whether internal or external to a device, such as random access memory (RAM), read-only memory (ROM), optical disc read-only memory (CDROM), electro-optical memory, magneto-optical memory, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), ferroelectric RAM (FRAM), etc. Memory can include any storage device (e.g., a device) adapted to store computer-executable instructions executable by a processing unit in a retrievable manner.

[0062] The methods and systems described herein may be implemented using high-level programs or object-oriented programming or scripting languages, or combinations thereof, to communicate with or assist in the operation of a controller or computing device. Alternatively, the methods and systems described herein may be implemented using assembly or machine language. The language may be a compiled or interpreted language. Program code used to implement the methods and systems described herein may be stored on a storage medium or device, such as ROM, disk, optical disk, flash drive, or any other suitable storage medium or device. The program code may be general-purpose or special-purpose programmable computer-readable, used to configure and operate the computer when the storage medium or device is read by a computer to perform the processes described herein.

[0063] Computer-executable instructions can take many forms, including modules, and can be executed by one or more computers or other devices. Generally, a module includes routines, programs, objects, components, data structures, etc., that perform a specific task or implement a specific abstract data type. Typically, the functionality of a module can be combined or distributed according to the needs of various implementation schemes.

[0064] It should be understood that systems and devices and their components may communicate via any of a variety of network protocols (such as TCP / IP, Ethernet, FTP, HTTP, etc.) and / or via a variety of wireless communication technologies (such as GSM, CDMA, Wi-Fi, and WiMAX), and the various computing devices described herein may be configured to communicate using any of these network protocols or technologies.

[0065] experiment

[0066] In simulations of the method according to the invention, a carbon monoxide reduction of at least 97% is achieved at a lower utility cost while ethylene loss is less than 0.2%.

[0067] Specific implementation plan

[0068] While the following description is presented in conjunction with specific embodiments, it should be understood that the description is intended to be illustrative and not to limit the scope of the foregoing description and the appended claims.

[0069] A first embodiment of the present invention is a method for separating carbon monoxide from ethylene, the method comprising cooling an ethylene stream with a refrigerant stream in a cooling zone; separating the ethylene stream into a liquid stream containing ethylene and an overhead stream containing carbon monoxide and ethylene in a fractionation zone including a fractionation tower; separating the overhead stream into a liquid portion and a gaseous portion in a vessel, wherein the gaseous portion contains carbon monoxide and ethylene; and absorbing ethylene from the gaseous portion with an absorbent liquid stream in an absorption zone to provide an enriched absorbent liquid containing an increased level of ethylene and a vapor of ethylene-lean containing carbon monoxide. An embodiment of the present invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, further comprising reboiling the stream from the fractionation tower with the ethylene stream before cooling the ethylene stream in the cooling zone. An embodiment of the present invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, further comprising heating the liquid stream from the fractionation tower with the ethylene stream before cooling the ethylene stream in the cooling zone. One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, which further includes cooling the overhead stream with a refrigerant stream in a cooling zone before separating the overhead stream in the container. One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, which further includes subcooling the refrigerant stream by transferring heat from the refrigerant stream to a portion of the liquid stream from the fractionation column. One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, which further includes subcooling the refrigerant stream by transferring heat from the refrigerant stream to a gaseous portion from the container. One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, wherein the absorbent liquid stream comprises a hydrocarbon stream. One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, wherein the hydrocarbon stream comprises oligomer effluent. One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, wherein the enriched absorbent is reboiled. Another embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, wherein the ethylene feed stream includes a portion of the dehydrated effluent.One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, wherein the ethylene feed stream has a pressure between 3,447 kPa and 4,137 kPa (500 psi (g) to 600 psi (g)), and the liquid feed stream has a pressure between 2,413 kPa and 3,103 kPa (350 psi (g) to 500 psi (g)). Another embodiment of the invention, one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, further includes recovering power from the pressure reduction of the lean ethylene vapor using an expansion device. Another embodiment of the invention, one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, further includes cooling the process feed stream with the liquid feed stream. One embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, which further includes separating a liquid ethylene stream into a liquid stream containing oxygen-containing compounds and an oxygen-containing fractionation zone overhead stream in an oxygen-containing compound fractionation zone including a fractionation column; and separating the oxygen-containing compound fractionation zone overhead stream into a liquid portion and a gaseous portion in a vessel, wherein the gaseous portion contains ethylene and carbon dioxide. Another embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, which further includes reboiling the stream from the fractionation column in the oxygen-containing compound fractionation zone with a hot process stream. Another embodiment of the invention is one, any, or all of the embodiments described in the preceding embodiments to the first embodiment described in this paragraph, which further includes cooling the oxygen-containing compound fractionation zone overhead stream with a refrigerant stream in a cooling zone before separating the overhead stream in the vessel.

[0070] A second embodiment of the invention is a method for producing spray-range hydrocarbons from bio-based alcohols, the method comprising dehydrating a bio-based alcohol stream in a dehydration zone comprising a reactor having a catalyst and operating under conditions providing a dehydrated effluent containing ethylene and carbon monoxide; separating carbon monoxide from ethylene in a fractionation zone from a feed stream containing a portion of the dehydrated effluent, the fractionation zone providing a bottom stream containing a carbon monoxide-lean ethylene stream and an overhead stream containing carbon monoxide and ethylene; and in an absorption zone using an absorbent liquid stream from the tower. A portion of the top feed stream absorbs ethylene to provide an enriched absorbent liquid stream containing increased levels of ethylene and a carbon monoxide-lean ethylene vapor stream; the carbon monoxide-lean liquid ethylene stream is oligomerized in an oligomerization zone comprising a reactor with a catalyst and operating under conditions providing oligomer effluent; the oligomer effluent is hydrogenated in a hydrogenation zone comprising a hydrogenation reactor with a catalyst and operating under conditions providing hydrogenated effluent; and the hydrogenated effluent is separated into one or more hydrocarbon streams containing jet fuel hydrocarbon vapor. One embodiment of the invention is one, any, or all of the embodiments described in the preceding to the second embodiments of this paragraph, wherein the absorbent liquid stream contains oligomer effluent. One embodiment of the invention is one, any, or all of the embodiments described in the preceding to the second embodiments of this paragraph, which further includes separating the overhead stream into a liquid portion and a gaseous portion in a container, wherein the gaseous portion includes the portion of the overhead stream that absorbs ethylene in the absorption zone; or cooling the overhead stream with a refrigerant stream in a cooling zone before separating the overhead stream; or both of the above. Another embodiment of the invention is one, any, or all of the embodiments described in the preceding to the second embodiments of this paragraph, which further includes separating oxygen-containing compounds from the carbon-monoxide-lean ethylene stream in an oxygen-containing compound fractionation zone, including a fractionation column, before oligomerizing the carbon-monoxide-lean ethylene stream, into a liquid stream containing oxygen-containing compounds and an overhead stream of the oxygen-containing compound fractionation zone.

[0071] Although no further detailed description has been provided, it is believed that those skilled in the art will be able to make full use of the invention by employing the foregoing description and will be able to readily identify the essential features of the invention without departing from its spirit and scope, and to make various changes and modifications to adapt it to various uses and situations. Therefore, the foregoing preferred embodiments should be understood as illustrative only and not as limiting the remainder of this disclosure in any way, and are intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.

[0072] In the foregoing, all temperatures are expressed in degrees Celsius, and all portions and percentages are by weight unless otherwise specified.

[0073] While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be understood that numerous variations exist. It should also be understood that one or more exemplary embodiments are merely examples and are not intended to limit the scope, applicability, or construction of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient roadmap for implementing exemplary embodiments of the invention, and it should be understood that various changes can be made to the function and arrangement of the elements described in the exemplary embodiments without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.

Claims

1. A method for separating carbon monoxide from ethylene, the method comprising: In the cooling zone (58), the ethylene stream (50) is cooled by the refrigerant stream (60); The ethylene stream is separated into a liquid stream (22) containing ethylene and an overhead stream (64) containing carbon monoxide and ethylene in a fractionation zone (16) including a fractionation tower (54). In container (72), the overhead feed stream (64) is separated into a liquid portion (74) and a gaseous portion (76), wherein the gaseous portion (76) comprises carbon monoxide and ethylene; and, In the absorption zone (66), the ethylene is absorbed from the gas section (76) by an absorbent liquid stream (80) to provide an enriched absorbent liquid (82) containing an increased level of ethylene and a vapor (84) containing carbon monoxide and ethylene-poor.

2. The method according to claim 1, further comprising: Before cooling the ethylene feed stream (50) in the cooling zone (58), the feed stream from the fractionation tower (54) is reboiled with the ethylene feed stream (50).

3. The method according to claim 1, further comprising: Before cooling the ethylene feed stream (50) in the cooling zone (58), the liquid feed stream (22) from the fractionation tower (54) is heated with the ethylene feed stream (50).

4. The method according to claim 1, further comprising: Before separating the overhead stream (64) in the container (72), the overhead stream (64) is cooled in the cooling zone (68) with a refrigerant stream (60).

5. The method according to claim 1, further comprising: The refrigerant stream (60) is subcooled by transferring heat from the refrigerant stream (60) to a portion of the liquid stream (22) from the fractionation tower (54).

6. The method according to claim 1, further comprising: The refrigerant stream (60) is subcooled by transferring heat from the refrigerant stream (60) to the gas portion (76) from the container (72).

7. The method according to any one of claims 1 to 6, wherein the absorbent liquid stream (80) comprises a hydrocarbon stream.

8. The method of claim 7, wherein the absorbent liquid stream (80) comprises an oligomer effluent, and / or wherein the ethylene stream (50) comprises a portion of a dehydrated effluent.

9. The method according to claim 7, wherein the enriched absorbent liquid (80) is reboiled.

10. The method according to any one of claims 1 to 6, wherein the ethylene feed stream (50) has a pressure between 3,447 kPa and 4,137 kPa (500 psi (g) to 600 psi (g)) and the liquid feed stream (22) has a pressure between 2,413 kPa and 3,103 kPa (350 psi (g) to 500 psi (g)).

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