Use of co2-rich gas as purge gas in chemical equipment

Abstract

The present invention provides a plant, such as a syngas plant, a hydrogen production plant, or a syngas and hydrogen co-production plant. The equipment comprises a reforming section, a CO2 removal section and a first electrolysis unit. A first portion of the first CO2-rich stream output from the CO2 removal section is configured to be supplied to the anode of the first electrolysis unit as a purge gas of an oxygen product gas; several streams from downstream of the first electrolysis unit are configured to be delivered as at least a portion of an oxygen-enriched feed to the reforming section. Various methods of producing hydrogen and / or syngas in the apparatus are also provided.

Description

Technical Field

[0001] Provided is a device, such as a synthesis gas device, a hydrogen production device or a synthesis gas and hydrogen co-production device. The device includes a reforming section, a CO 2 Removal stage and first electrolysis unit. From CO 2 The first CO-rich 2 A first portion of the stream is configured to be supplied to the anode of the first electrolysis unit as a purge gas for the oxygen product gas. Several streams downstream of the first electrolysis unit are configured to be delivered to the reforming section as at least a portion of the oxygen-rich feed. A variety of methods for producing hydrogen and / or synthesis gas in the apparatus are also provided. Background Art

[0002] There is an increasing demand for the use of electrolysis technology in industrial chemical plants and processes to produce gas streams such as oxygen or hydrogen, especially in light of environmental concerns and the growing opportunities to utilize electricity from renewable sources.

[0003] An autothermal reformer (ATR) is used to provide a synthesis gas (syngas) stream from a hydrocarbon-rich stream. The ATR typically includes a burner, a combustion chamber, and a catalyst bed contained in a refractory-lined pressure shell. In the ATR, hydrocarbons are partially burned by substoichiometric oxygen and subsequently steam reformed. Therefore, the ATR needs to provide oxygen as a co-feed for the combustion of the burner. This oxygen stream is typically provided by an air separation unit (ASU). The cost of the ASU is relatively high.

[0004] The oxygen stream from an industrial-scale electrolysis process, such as that carried out in a solid oxide electrolysis cell (SOEC), is generally considered a waste product and is discharged directly into the atmosphere. If the oxygen stream produced by such an industrial-scale electrolysis process is to be effectively utilized, it is generally necessary to use a so-called "purge gas". The purge gas is fed to the anode side of the electrolyzer, where it mixes with the oxygen produced at the anode. Subsequently, a mixed gas stream comprising oxygen is output from the electrolyzer. The use of a purge gas can provide a mixed gas stream having a higher pressure than the oxygen stream produced in the electrolyzer, and can be used, for example, to adjust the chemical and physical composition of the oxygen stream to meet the requirements of a specific application.

[0005] Atmospheric air is often used as the purge gas, which has the advantage of being readily available. However, if atmospheric air is recycled as the purge gas to other parts of the chemical plant (such as the ATR), this may lead to the accumulation of inert nitrogen.

[0006] US8496908 describes a method for producing a hydrogen product and capturing CO from the process 2 Steam methane reforming process.

[0007] WO2021 / 156457 describes a method for supplying oxygen-rich gas to an aerobic process. In contrast, the present invention requires CO 2 As a reactant in the oxygen-rich feed to the reforming stage, rather than just a by-product. 2 It is the carbon raw material in the reforming reaction to achieve the best utilization of carbon. 2 It is removed downstream of the reforming stage and recycled.

[0008] Currently, there is still a need for an energy efficient source of oxygen for ATR in chemical plants. In addition, there is a need for efficient utilization of waste streams in chemical plants. The present technology solves these problems and achieves other goals. Summary of the invention

[0009] An apparatus and method have been developed which reduces the production of O-rich 2 The equipment may be a hydrogen production equipment, a synthesis gas equipment or a hydrogen and synthesis gas co-production equipment.

[0010] Therefore, in a first embodiment, the present invention relates to a device comprising:

[0011] - Mixed feed of steam and hydrocarbons;

[0012] - comprising a reforming section of an autothermal reformer, the reforming section being configured to receive the mixed feed and the oxygen-enriched feed and to provide a first synthesis gas stream;

[0013] -CO 2 a removal section configured to receive the first synthesis gas stream and provide a first hydrogen-rich stream and a first CO-rich stream 2 flow;

[0014] - a first electrolysis unit comprising an anode and a cathode;

[0015] - a first electrolysis feed, supplied to the first electrolysis unit;

[0016] wherein the first electrolysis unit is configured to electrolyze a first electrolysis feed into at least an oxygen product gas and a cathode product gas stream;

[0017] And among them,

[0018] From CO 2 The first CO-rich 2 at least a first portion of the stream is configured to be supplied to an anode of a first electrolysis unit as a purge gas for an oxygen product gas, thereby outputting a first mixed gas stream comprising carbon dioxide and oxygen from the electrolysis unit;

[0019] - Optionally, a first water removal stage and a CO 2A separation unit, wherein a first water removal section is configured to receive at least a portion of the first mixed gas stream from the first electrolysis unit and provide at least a first water-rich stream and a second mixed gas stream; and wherein the CO 2 The separation unit is configured to receive at least a portion of the second mixed gas stream from the first water removal stage and provide at least a second CO-rich 2 flow and oxygen-enriched flow;

[0020] And wherein one or more streams selected from the following are configured to be delivered to the reforming section as at least a portion of the oxygen-rich feed:

[0021] o at least a portion of the mixed gas flow from the first electrolysis unit,

[0022] o the second portion of the second mixed gas stream, if present, and

[0023] o At least a portion of the oxygen-enriched stream, if present.

[0024] There is also provided a method for producing hydrogen and / or synthesis gas in the apparatus of the invention, the method comprising the following steps:

[0025] - providing a device according to the invention;

[0026] - conveying a mixed feed of steam and hydrocarbons and an oxygen-enriched feed to a reforming section comprising an autothermal reformer to provide a first synthesis gas stream;

[0027] - The first synthesis gas stream is delivered to the CO 2 The removal section provides a first hydrogen-rich stream and a first CO-rich stream. 2 flow;

[0028] - conveying a first electrolysis feed to a first electrolysis unit and electrolyzing it into at least an oxygen product gas and a cathode product gas stream;

[0029] - will come from CO 2 The first CO-rich 2 supplying at least a first portion of the stream to an anode of a first electrolysis unit as a purge gas for the oxygen product gas, and outputting a first mixed gas stream comprising carbon dioxide and oxygen from the electrolysis unit;

[0030] - Optionally, the device comprises a first water removal stage and a CO 2 In the case of separation units,

[0031] o passing at least a portion of the first mixed gas stream from the first electrolysis unit to a first water removal stage to provide at least a first water-rich stream and a second mixed gas stream; and o passing at least a portion of the second mixed gas stream from the first water removal stage to a CO 2separation unit to provide at least a second CO-rich 2 flow and oxygen-enriched flow;

[0032] The method comprises the additional step of conveying one or more streams selected from the following as at least a portion of the oxygen-rich feed to the reforming section:

[0033] o at least a portion of the mixed gas flow from the first electrolysis unit,

[0034] o the second portion of the second mixed gas stream, if present, and

[0035] o At least a portion of the oxygen-enriched stream, if present.

[0036] Further details of the technology can be found in the accompanying drawings, claims and specification text.

[0037] The present invention is based on the recognition that the CO 2 Recycling CO in the removal stage 2 It is used as a purge gas on the anode side of the electrolyzer to purge the oxygen produced therein. The present invention is also based on the following recognition: when using CO 2 When used as a purge gas, it is possible to avoid the need to purify the combined oxygen and purge gas stream prior to use in the autothermal reformer because, unlike nitrogen in atmospheric air, CO 2 is not an undesirable component in an autothermal reformer. The present invention is also based on the recognition that the CO 2 The recycling of optimizes the carbon mass balance of the plant of the present invention so that all of the carbon input to the plant is available for forming the syngas product.

[0038] Finally, in contrast to using an oxygen feed formed from an air separation unit (ASU), the oxygen from the anode side of the electrolyser does not contain any contaminants (such as argon, nitrogen and helium) which need to be separated before use in the autothermal reformer.

[0039] BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The following schematic diagram is provided, where:

[0041] Figure 1 The overall layout of the equipment is shown.

[0042] Figure 2A and Figure 2B Different variants of hydrogen production plants are shown.

[0043] Figure 3 The layout of a synthesis gas plant is shown.

[0044] Figure 4 Shown based on Figure 1 Layout, the overall layout of the equipment. DETAILED DESCRIPTION OF THE INVENTION

[0046] Unless otherwise stated, any percentages of gas content are expressed as volume percentages.

[0047] The term "synthesis gas" (abbreviated as "syngas") refers to a gas containing hydrogen, carbon monoxide, carbon dioxide, steam and small amounts of other gases (such as argon, nitrogen, methane, etc.).

[0048] The term "purge gas" refers to the gas supplied to the electrolysis cell which serves as a carrier for the O 2 The purge gas is carried out of the electrolysis unit without any chemical reaction or conversion of the chemical components of the purge gas during its passage through the electrolysis unit.

[0049] An apparatus is provided, which generally comprises:

[0050] - Mixed feed of steam and hydrocarbons;

[0051] - A reforming section comprising an autothermal reformer;

[0052] -CO 2 Remove segments;

[0053] - a first electrolysis unit comprising an anode and a cathode;

[0054] - a first electrolysis feed, supplied to the first electrolysis unit;

[0055] - Optionally, a first water removal stage and a CO 2 Separation unit.

[0056] Mixed feed

[0057] A mixed feed of steam and hydrocarbon is provided. The mixed feed is usually provided by mixing a steam feed and a hydrocarbon feed. The hydrocarbon feed may be a feed such as natural gas, LPG, naphtha, and hydrocarbon-containing tail gas produced from other equipment / processes. The hydrocarbon feed is preferably rich in methane, for example, it contains more than 90% methane, such as more than 95% methane, preferably more than 98% methane.

[0058] The mixed feed is conveyed to a reforming section, in particular an ATR, where it is converted into a first synthesis gas stream.

[0059] Reorganization section

[0060] The reforming section includes an autothermal reformer (ATR) and is configured to receive the mixed feed and the oxygen-enriched feed and provide a first synthesis gas stream.

[0061] An ATR typically comprises a burner, a combustion chamber, and a catalyst bed contained within a refractory-lined pressure shell. In an ATR, hydrocarbons are partially combusted by substoichiometric oxygen and subsequently steam reformed in a fixed bed of steam reforming catalyst - the reverse of reactions (1) and (2).

[0062]

[0063] Typically, the gas is at or near equilibrium with respect to the steam reforming reaction and the water gas shift reaction at the reactor outlet. For more details and a complete description of ATR, refer to the prior art, such as "Studies in Surface Science and Catalysis, Vol. 152," Synthesis gas production for FT synthesis "; Chapter 4, p. 258-352, 2004".

[0064] The composition of the first synthesis gas stream is suitably as follows:

[0065] -H 2 : 65-75% (dry basis),

[0066] -CO: 15-30% (dry basis),

[0067] -CO 2 : 4-8% (dry basis),

[0068] -CH 4 : 1.5-6% (dry basis).

[0069] The oxygen-enriched feed provides the required oxygen for the burner of the ATR. The oxygen-enriched feed suitably comprises more than 50% oxygen, such as more than 60% oxygen, preferably more than 90% oxygen, preferably more than 99% oxygen.

[0070] The oxygen-enriched feed conveniently comprises up to 50% CO 2 , such as up to 30% CO 2 , preferably up to 20% CO 2 , preferably up to 10% CO 2 .

[0071] The oxygen-enriched feed to the reforming section is generated by one or more other components of the plant, as described below. Other components of the oxygen-enriched feed may include H 2 O and CO 2 .

[0072] The reforming section may further include a pre-reformer, which is arranged upstream of the autothermal reformer, configured to pre-reform the mixed feed to form a pre-reformed mixed feed, and configured to transport the pre-reformed mixed feed to the autothermal reformer. In the pre-reformer, higher hydrocarbons in the natural gas feed are converted into methane, thereby reducing the formation of coke in the main reformer.

[0073] CO 2 Remove Segment

[0074] CO 2 The removal section is configured to receive the first synthesis gas stream and provide a first hydrogen-rich stream and a first CO-rich stream. 2 flow.

[0075] CO removal 2 Provides low CO 2 The hydrogen-rich stream has a content of, for example, less than 2%, 1%, preferably less than 0.5%, more preferably less than 0.1% (on a dry basis).

[0076] CO2-rich 2 The stream typically contains at least 99% (e.g., 99.8%) dry basis CO 2 and less than 1% (e.g. 0.2%) dry basis H 2 . CO rich 2 The main impurity in the flow is H 2 Other impurities include Ar, CH 4 , CO 2 、N 2 , whose content may be in the (negligible) ppm level.

[0077] If CO 2 The removal section is located upstream of the PSA unit and is conveniently a solvent based unit such as an amine wash unit. 2 The removal section is located downstream of the PSA unit and is conveniently a cryogenic unit.

[0078] First electrolysis unit

[0079] A first electrolysis feed is provided to a first electrolysis unit. The first electrolysis unit is configured to electrolyze the first electrolysis feed into at least an oxygen product gas and a cathode product gas stream. The first electrolysis unit comprises an anode and a cathode. Preferably, the first electrolysis unit is one or more solid oxide electrolysis cells (SOECs). The design and construction of SOECs are known, for example, with reference to WO2013 / 164172, the contents of which are incorporated herein by reference. Alternatively, the first electrolysis unit in the apparatus of the present invention may be an alkaline electrolyzer or a proton exchange membrane (PEM) electrolyzer.

[0080] Depending on the desired product, the first electrolysis feed can be a water-rich feed or a CO-rich feed. 2In one aspect, the first electrolysis feed is a water-rich feed, and the first electrolysis unit is configured to electrolyze the first electrolysis feed into oxygen as an anode product gas and hydrogen as a cathode product gas. In another aspect, the first electrolysis feed is a CO-rich feed. 2 The first electrolysis unit is configured to electrolyze the first electrolysis feed into oxygen as an anode product gas and carbon monoxide as a cathode product gas. In a further aspect, the first electrolysis feed may be a CO-rich 2 feed, and may also contain water.

[0081] From CO 2 The first CO-rich 2 At least a first portion of the flow is configured to be supplied to the anode of the first electrolysis unit as a purge gas for the oxygen product gas (also referred to as "purge gas"), thereby outputting a first mixed gas flow comprising carbon dioxide and oxygen from the electrolysis unit. 2 Acting as a purge gas reduces the buildup of inert gases, such as nitrogen, that would otherwise be produced if atmospheric air were used as the purge gas.

[0082] When using CO 2 When used as a purge gas, the purge gas stream leaving the electrolyser contains only O 2 and CO 2 , usually 50% each. This purge gas can be used directly in the ATR burner, or mixed with additional O, for example from an air separation unit (ASU). 2 Mixing. Using this purge gas stream will reduce energy consumption and lower the cost of the ASU. 2 Can be recycled in the process and used in downstream CO 2 Alternatively, CO in the purge gas leaving the SOEC 2 can be removed, for example by separation by condensation, to obtain pure O for the ATR burner 2 stream and pure CO that can be recycled back to the SOEC 2 flow.

[0083] A portion of the mixed gas stream from the first electrolysis unit may be configured to be delivered (ie delivered directly) to the reforming stage as at least a portion of said oxygen-rich feed.

[0084] Alternatively, or in addition, at least a portion of the mixed gas stream may be further purified before being sent to the reforming stage. 2 Separation unit. The first water removal section and CO 2The separation units are arranged in series to purify the mixed gas stream. The first water removal section (if present) is configured to receive at least a portion of the first mixed gas stream from the first electrolysis unit and provide at least a first water-rich stream and a second mixed gas stream. 2 The separation unit, if present, is configured to receive at least a portion of the second mixed gas stream from the first water removal stage and provide at least a second CO-rich 2 flow and oxygen-enriched flow.

[0085] As mentioned above, one or more oxygen-containing gas streams can be used as the oxygen-enriched feed of the reforming section. In the present invention, one or more streams selected from the following are configured to be delivered to the reforming section as at least a portion of the oxygen-enriched feed:

[0086] - at least a part of the mixed gas flow coming from the first electrolysis unit,

[0087] - if present, the second portion of the second mixed gas stream, and

[0088] - at least a portion of said oxygen-enriched stream, if present.

[0089] Preferably, the apparatus comprises a first water removal stage and a CO 2 separation unit, and from CO 2 At least a portion of the oxygen-rich stream of the separation unit is configured to be passed to the reforming section as at least a portion of the oxygen-rich feed.

[0090] The oxygen content of the oxygen-enriched feed supplied to the reforming section depends on the origin of the stream constituting the oxygen-enriched feed. If the oxygen-enriched feed is supplied by the first electrolysis unit (i.e., it comes from at least a portion of the mixed gas stream of the first electrolysis unit), it comprises O 2 , CO 2 and water.

[0091] If the oxygen-enriched feed is supplied by the first water removal stage (i.e., it is at least part of the second mixed gas stream from the first water removal stage), its oxygen content may be higher than the oxygen content of the first electrolysis unit output stream, the major remaining component of which is CO. 2 .

[0092] If the oxygen-rich feed is supplied by the first water removal stage (i.e., it is from CO 2 If at least a portion of the oxygen-rich stream of the separation unit is present, its oxygen content may exceed 99%.

[0093] In one aspect, at least a portion of the first water-rich stream from the first water removal stage is provided as part of the first water-rich feed to the first electrolysis unit.Additional oxygen feed may be provided as at least a portion of the oxygen-rich feed, for example during startup.

[0094] For example, during startup, a portion of the oxygen-rich feed may be provided from a different source, such as an ASU.

[0095] Hydrogen production equipment

[0096] The device of the present invention may be a hydrogen production device, and thus may further include a shift section, wherein the shift section is configured to receive the first synthesis gas stream from the reforming section and to convert the first synthesis gas stream into a CO 2 The removal section provides a shifted first synthesis gas stream, thereby promoting hydrogen production.

[0097] In the hydrogen production equipment, the first electrolysis feed is a water-rich feed, so the first electrolysis unit is configured to electrolyze the first electrolysis feed into an oxygen product gas. The cathode product gas stream is a hydrogen-rich product stream.

[0098] The hydrogen production equipment includes the first water removal stage and the CO 2 Separation unit. Oxygen-rich stream (from CO 2 At least a portion of the separation unit) is configured to be delivered to the reforming section as at least a portion of the oxygen-rich feed.

[0099] From CO 2 The first hydrogen-rich stream of the removal stage can be provided as a crude hydrogen stream from a hydrogen production facility. If desired, the hydrogen production facility can also include a pressure swing adsorption (PSA) unit configured to receive the crude hydrogen stream from the CO 2 The first hydrogen-rich stream of the removal section is removed to provide a purified hydrogen stream and a PSA tail gas stream. The PSA tail gas (mainly comprising H 2 and CH 4 ) can be used as feed or fuel for other parts of the equipment, or output from the equipment.

[0100] In another configuration (such as Figure 2B As shown), the PSA unit is located between the conversion section and the CO 2 The PSA unit is configured to receive the converted first synthesis gas stream from the conversion section and provide a purified hydrogen stream and a PSA tail gas stream, while the PSA tail gas stream is delivered to the CO 2 Removal segment. The CO 2 The removal section removes CO from the PSA tail gas stream 2 , generating the first CO-rich 2 flow (sent to the electrolysis stage as described above) and CO 2 The tail gas stream is removed. A condensate stream is also provided, which mainly contains water. 2 The tail gas stream from the removal section can be used as feed to the reformer or as fuel for the combustion heater as required.

[0101] In one aspect, the hydrogen production facility includes a second water removal section configured to receive at least a first portion of the hydrogen-rich product stream from the first electrolysis unit and provide at least a second water-rich stream and a second purified hydrogen stream. The second purified hydrogen stream can be output from the hydrogen production facility as a supplement to the first hydrogen-rich stream.

[0102] If further purification of the second purified hydrogen stream is desired, it may be delivered to a PSA unit. In other words, at least a second portion of the hydrogen-rich product stream from the first electrolysis unit may be configured to be delivered to the inlet of the PSA unit, typically together with the hydrogen from the CO 2 The first hydrogen-rich stream of the removal section is mixed.

[0103] Syngas Equipment

[0104] The device may be a synthesis gas device. In this embodiment, the first electrolysis feed is a water-rich feed, and the first electrolysis unit is configured to electrolyze the first electrolysis feed into a cathode product gas stream, and the cathode product gas stream is a synthesis gas product stream.

[0105] In this embodiment, the oxygen-rich feed to the reforming section does not need to have a high oxygen content. Therefore, at least a portion of the mixed gas flow from the first electrolysis unit is configured to be delivered to the reforming section as at least a portion of the oxygen-rich feed.

[0106] In this embodiment, the CO 2 The first CO-rich 2 The stream may have another use; namely as feed to the first electrolysis unit. In other words, the first electrolysis feed may include the CO 2 The first CO-rich 2 The second part of the stream.

[0107] CO used as feed for electrolysis unit 2 Also from CO 2 Separation unit. In this case, the first electrolysis feed includes the CO 2 The second CO-rich separation unit 2 at least a portion of a flow.

[0108] The syngas plant may further comprise a second water removal section. The second water removal section may be configured to receive at least a portion of the first hydrogen-rich stream and provide at least a second water-rich stream and a second mixed gas stream.

[0109] Second electrolysis unit

[0110] The device (hydrogen production device or synthesis gas device) may also include a second electrolysis unit. The second electrolysis unit provides flexibility for the input flow of the device. The second electrolysis unit may include one or more solid oxide electrolysis cells (SOEC). Alternatively, the second electrolysis unit in the device of the present invention may be an alkaline electrolysis cell or a proton exchange membrane (PEM) electrolysis cell.

[0111] In this embodiment, the CO 2 The first CO-rich 2 The second portion of the flow may be configured to be supplied as an electrolysis feed to a second electrolysis unit. The second electrolysis unit is configured to convert the first CO-rich 2 A second portion of the stream is electrolyzed into an oxygen product gas and a CO-containing stream.

[0112] From CO 2 The first CO-rich 2 The third portion of the flow is configured to be supplied to the anode of the second electrolysis unit as a purge gas for the oxygen product gas, thereby outputting a first mixed gas flow comprising carbon dioxide and oxygen from the second electrolysis unit.

[0113] In this embodiment, the water feed can be configured to be mixed with the first CO-rich 2 The second part of the flow is mixed upstream of the second electrolysis unit. The water is mixed with the CO rich 2 The co-electrolysis of the flow will produce H 2 Therefore, the electrolysis products (CO-containing stream) will be CO and H 2 The resulting mixture, syngas, can be used to produce methanol or other chemicals.

[0114] The second electrolysis unit allows the production of H in the main line 2 , and the second electrolysis unit passes CO 2 Syngas production can also be carried out in the main production line, while a second electrolysis unit can provide H by water electrolysis. 2 .

[0115] Additional Units

[0116] The apparatus may include a second water removal section configured to receive at least a first portion of the hydrogen-rich product gas stream from the first electrolysis unit and provide at least a second water-rich stream and a second purified hydrogen stream. The second purified hydrogen stream may be output from the apparatus as a hydrogen product, optionally along with the first hydrogen stream.

[0117] In one aspect, at least a portion of the second water-rich stream from the second water removal stage is provided as part of the first water-rich feed to the first electrolysis unit.

[0118] The apparatus may further include a second water removal stage configured to receive at least a portion of the first hydrogen-rich stream and provide at least a second water-rich stream and a second mixed gas stream.

[0119] method

[0120] The present invention also provides several methods implemented in the above device.

[0121] A method for producing hydrogen and / or synthesis gas in the device is provided. The method comprises the following steps:

[0122] - providing a device as described herein;

[0123] - conveying a mixed feed of steam and hydrocarbons and an oxygen-enriched feed to a reforming section comprising an autothermal reformer to provide a first synthesis gas stream;

[0124] - The first synthesis gas stream is delivered to the CO 2 The removal section provides a first hydrogen-rich stream and a first CO-rich stream. 2 flow;

[0125] - conveying a first electrolysis feed to a first electrolysis unit and electrolyzing it into at least an oxygen product gas and a cathode product gas stream;

[0126] - will come from CO 2 The first CO-rich 2 supplying at least a first portion of the stream to an anode of a first electrolysis unit as a purge gas for the oxygen product gas, and outputting a first mixed gas stream comprising carbon dioxide and oxygen from the electrolysis unit;

[0127] - Optionally, the device comprises a first water removal stage and a CO 2 In the case of separation units,

[0128] o conveying at least a portion of the first mixed gas stream from the first electrolysis unit to a first water removal stage to provide at least a first water-rich stream and a second mixed gas stream; and

[0129] o passing at least a portion of the second mixed gas stream from the first water removal stage to the CO 2 separation unit, and provide at least a second CO-rich 2 flow and oxygen-enriched flow;

[0130] The method comprises the additional step of conveying one or more streams selected from the following as at least a portion of the oxygen-rich feed to the reforming section:

[0131] o at least a portion of the mixed gas flow from the first electrolysis unit,

[0132] o the second portion of the second mixed gas stream, if present, and

[0133] o At least a portion of the oxygen-enriched stream, if present.

[0134] A method for producing hydrogen in the hydrogen production plant described herein is also provided. The method comprises the following steps:

[0135] - providing a hydrogen production plant according to the present invention;

[0136] - conveying a mixed feed of steam and hydrocarbons and an oxygen-enriched feed to a reforming section comprising an autothermal reformer to provide a first synthesis gas stream;

[0137] - conveying the first synthesis gas stream from the reforming section to the shift section to provide the shifted first synthesis gas stream to the CO 2 Remove segments;

[0138] - The shifted first synthesis gas stream is sent to the CO 2 The removal section provides a first hydrogen-rich stream and a first CO-rich stream. 2 flow;

[0139] - conveying a first electrolysis feed, which is a water-rich feed, to a first electrolysis unit and electrolyzing it into at least an oxygen product gas and a cathode product gas stream, the cathode product gas stream being a hydrogen-rich product stream;

[0140] - will come from CO 2 The first CO-rich 2 supplying at least a first portion of the stream to an anode of a first electrolysis unit as a purge gas for the oxygen product gas, and outputting a first mixed gas stream comprising carbon dioxide and oxygen from the electrolysis unit;

[0141] - conveying at least a portion of said first mixed gas stream from a first electrolysis unit to a first water removal stage to provide at least a first water-rich stream and a second mixed gas stream; and

[0142] - conveying at least a portion of the second mixed gas stream from the first water removal stage to the CO 2 separation unit to provide at least a second CO-rich 2 flow and oxygen-enriched flow;

[0143] The method comprises the additional step of conveying at least a portion of the oxygen-rich stream as at least a portion of the oxygen-rich feed to a reforming section.

[0144] A method for producing synthesis gas in the synthesis gas plant described herein is also provided. The method comprises the following steps:

[0145] - providing a synthesis gas plant according to the invention;

[0146] - conveying a mixed feed of steam and hydrocarbons and an oxygen-enriched feed to a reforming section comprising an autothermal reformer to provide a first synthesis gas stream;

[0147] - conveying the first synthesis gas stream from the reforming section to the shift section to provide the shifted first synthesis gas stream to the CO 2 Remove segments;

[0148] - The shifted first synthesis gas stream is sent to the CO 2 The removal section provides a first hydrogen-rich stream and a first CO-rich stream. 2 flow;

[0149] - conveying a first electrolysis feed, which is a water-rich feed, to a first electrolysis unit and electrolyzing it into at least an oxygen product gas and a cathode product gas stream, the cathode product gas stream being a synthesis gas product stream;

[0150] - will come from CO 2 The first CO-rich 2 at least a first portion of the stream is delivered to an anode of a first electrolysis unit as a purge gas for the oxygen product gas, and a first mixed gas stream comprising carbon dioxide and oxygen is output from the electrolysis unit;

[0151] - conveying at least a part of the first mixed gas flow coming from the first electrolysis unit to the reforming section as at least a part of said oxygen-rich feed.

[0152] According to this embodiment, the method may further include: 2 The first CO-rich 2 The step of delivering a second portion of the stream to a first electrolysis unit as at least a portion of the first electrolysis feed.

[0153] All details of the device described in the invention are applicable mutatis mutandis to the method described. DETAILED DESCRIPTION

[0154] Figure 1 The general layout of the plant (100) is shown. A mixed feed (3) of steam (2) and hydrocarbon (1) is fed to the reforming section (10) together with an oxygen-rich feed (4) to provide a first synthesis gas stream (11). The first synthesis gas stream (11) is fed to the CO 2 removing section (30) and providing a first hydrogen-rich stream (31) and a first CO-rich stream 2 Flow (32).

[0155] The first electrolysis feed (9) (e.g. water, CO 2or a mixture thereof) is provided to a first electrolysis unit (40) where it is electrolyzed into at least an oxygen product gas and a cathode product gas stream (45).

[0156] From CO 2 The first CO-rich removal section (30) 2 A first portion (32a) of stream (32) is supplied to the anode of the first electrolysis unit (40) as a purge gas for the oxygen product gas. 2 The first CO-rich removal section (30) 2 Another portion (32d) of the stream (32) may be output, as not all of the stream needs to be recirculated through the electrolysis unit (40). A first mixed gas stream (41) comprising carbon dioxide and oxygen from the electrolysis unit (40) is output from the first electrolysis unit (40).

[0157] Figure 1 Also shown is the first water removal stage (50) and the CO 2 The first water removal section (50) is configured to receive at least a portion (41a) of the first mixed gas stream (41) from the first electrolysis unit (40) and provide at least a first water-rich stream (51) and a second mixed gas stream (52). 2 The separation unit (60) is configured to receive at least a portion (52a) of the second mixed gas stream (52) from the first water removal stage (50) and provide at least a second CO-rich 2 flow (61) and an oxygen-enriched flow (62).

[0158] like Figure 1 As shown, one or more streams are configured to be delivered to the reforming section (10) as at least a portion of the oxygen-rich feed (4). These feeds are selected from:

[0159] - at least a portion (41b) of the mixed gas flow (41) coming from the first electrolysis unit (40),

[0160] - if present, the second portion (52b) of the second mixed gas flow (52), and

[0161] - at least a portion of the oxygen-rich stream (62), if present.

[0162] Additional oxygen feed (6) may be supplied as at least part of the oxygen-enriched feed, for example during start-up.Steam feed (5) may be supplied to the reforming section (10).

[0163] Figure 2A and Figure 2B Shown based on Figure 1 These figures contain different variants of the layout of the hydrogen production plant. Figure 1 The same elements are described with the addition of the following: a shift section (20), a PSA unit (70) which produces purified hydrogen (71) and a PSA tail gas stream (72), and a second water removal section (80) which provides a second water-rich stream (81) and a second purified hydrogen stream (82). Figure 2A In the PSA unit, the CO 2 Downstream of the removal section (30), Figure 2B In the PSA unit, the CO 2 Removal section (30) upstream. A purified hydrogen stream (71) is output from the apparatus. In this embodiment, the first electrolysis feed (9) is a water-rich feed.

[0164] Figure 3 Shown based on Figure 1 Layout of the synthesis gas plant. Figure 3 Contains Figure 1 In this embodiment, the first electrolysis feed (9) is a water-rich feed, which may include water from CO 2 The first CO-rich removal section (30) 2 The cathode product gas stream (45) from the first electrolysis unit (40) is the synthesis gas product stream (43), which is output from the plant. 2 The recycle stream (36) is derived from CO 2 The removal section (30) is sent to the reforming section (10). It may not be possible to recycle all of the first CO-rich gas through the first electrolysis unit (40). 2 Flow (32).

[0165] Figure 4 Shown based on Figure 1 The overall layout of the equipment is shown in FIG. The layout includes a second electrolysis unit (140). 2 The first CO-rich removal section (30) 2 The second portion (32b) of the stream (32) is configured to be supplied to a second electrolysis unit (140) as an electrolysis feed. The second electrolysis unit (140) converts the first CO-rich 2 A second portion (32b) of stream (32) is electrolyzed into an oxygen product gas and a CO-containing stream (142). In addition, the CO 2 The first CO-rich removal section (30) 2 A third portion (32c) of the stream (32) is supplied to the anode of the second electrolysis unit (140) as a purge gas for the oxygen product gas, thereby outputting a first mixed gas stream (141) containing carbon dioxide and oxygen from the second electrolysis unit (140).

[0166] Although the invention has been described in terms of several aspects and embodiments, those skilled in the art may combine these aspects and embodiments within the scope of the appended claims.All documents cited herein are incorporated herein by reference.

Claims

1. A device (100), the device (100) include: - a mixed feed (3) of steam (2) and hydrocarbons (1); a reforming section (10) comprising an autothermal reformer, the reforming section (10) being configured to receive the mixed feed (3) and the oxygen-enriched feed (4) and to provide a first synthesis gas stream (11); -CO 2 The removal section (30) is configured to receive the first synthesis gas stream (11) and provide a first hydrogen-rich stream (31) and a first CO-rich stream (32). 2 stream (32); - a first electrolysis unit (40) comprising an anode and a cathode; - a first electrolysis feed (9) which is supplied to the first electrolysis unit (40); wherein the first electrolysis unit (40) is configured to electrolyze a first electrolysis feed (9) into at least an oxygen product gas and a cathode product gas stream (45); And among them, From CO 2 The first CO-rich removal section (30) 2 At least a first portion (32a) of the stream (32) A purge gas configured to be supplied to the anode of the first electrolysis unit (40) as the oxygen product gas, thereby outputting a first mixed gas stream (41) containing carbon dioxide and oxygen from the electrolysis unit (40); - Optionally, a first water removal stage (50) and CO 2 A separation unit (60), wherein a first water removal section (50) is configured to receive at least a portion (41a) of the first mixed gas stream (41) from the first electrolysis unit (40) and provide at least a first water-rich stream (51) and a second mixed gas stream (52); and wherein the CO 2 The separation unit (60) is configured to receive at least a portion (52a) of the second mixed gas stream (52) from the first water removal stage (50) and provide at least a second CO-rich 2 flow (61) and an oxygen-enriched flow (62); And, one or more streams selected from the following are configured to be delivered to the reforming section (10) as at least a part of the oxygen-rich feed (4): O at least a portion (41b) of the mixed gas flow (41) from the first electrolysis unit (40), O the second portion (52b) of the second mixed gas stream (52), if present, and O If present, at least a portion of the oxygen-enriched stream (62).

2. The device (100) according to claim 1, wherein the reforming section (10) further comprises a pre-reformer arranged upstream of the autothermal reformer, the pre-reformer being configured to pre-reform the mixed feed (3) to form a pre-reformed mixed feed, and being configured to transport the pre-reformed mixed feed to the autothermal reformer.

3. An apparatus (100) according to any of the preceding claims, wherein the first electrolysis feed (9) is a water-rich feed, and wherein the first electrolysis unit (40) is configured to electrolyze the first electrolysis feed (9) into oxygen as an anode product gas and hydrogen as a cathode product gas.

4. The apparatus (100) according to any one of claims 1 to 2, wherein the first electrolysis feed (9) is CO-rich 2 feed, and wherein the first electrolysis unit (40) is configured to electrolyze the first electrolysis feed (9) into oxygen as an anode product gas and carbon monoxide as a cathode product gas.

5. The device (100) according to any one of the preceding claims, which is a hydrogen production device, and the device (100) also include: a shift section (20) configured to receive the first synthesis gas stream (11) coming from the reforming section (10), And to CO 2 The removal section (30) provides a shifted first synthesis gas stream (11a), wherein the first electrolysis feed (9) is a water-rich feed, wherein the first electrolysis unit (40) is configured to electrolyze the first electrolysis feed (9) into an oxygen product gas, and wherein the cathode product gas stream (45) is a hydrogen-rich product stream (42), The hydrogen production equipment comprises a first water removal section (50) and a CO 2 A separation unit (60), wherein a first water removal section (50) is configured to receive at least a portion (41a) of the first mixed gas stream (41) from the first electrolysis unit (40) and provide at least a first water-rich stream (51) and a second mixed gas stream (52); wherein the CO 2 The separation unit (60) is configured to receive at least a portion (52a) of the second mixed gas stream (52) from the first water removal stage (50) and provide at least a second CO-rich 2 flow (61) and an oxygen-enriched flow (62); Furthermore, at least a portion of the oxygen-rich stream (62) is configured to be delivered to the reforming section (10) as at least a portion of the oxygen-rich feed (4).

6. The apparatus (100) according to claim 5, further comprising a pressure swing adsorption (PSA) unit (70), wherein the PSA unit (70) is configured to receive the CO 2 The first hydrogen-rich stream (31) of stage (30) is removed and a purified hydrogen stream (71) and a PSA tail stream (72) are provided.

7. The apparatus (100) according to claim 5, further comprising a pressure swing adsorption (PSA) unit (70), wherein the PSA unit (70) is configured to receive the shifted first synthesis gas stream (11a) from the shift stage (20), and provide a purified hydrogen gas stream (71) and a PSA tail gas stream (72), and to deliver the PSA tail gas stream (72) to the CO 2 Segment (30) is removed.

8. The apparatus (100) according to any one of claims 4 to 7, wherein the following stream is also configured to be conveyed to the reforming section (10) as at least a part of the oxygen-rich feed (4): O at least a portion (41b) of the mixed gas stream (41) from the first electrolysis unit (40), and / or O A second portion (52b) of the second mixed gas flow (52).

9. The apparatus (100) according to any one of claims 4-8, wherein the apparatus comprises a second water removal section (80), the second water removal section (80) being configured to receive at least a first portion (42a) of the hydrogen-rich product stream (42) from the first electrolysis unit (40) and to provide at least a second water-rich stream (81) and a second purified hydrogen stream (82).

10. The apparatus (100) of claim 9, wherein the second portion (42b) of the hydrogen-rich product stream (42) from the first electrolysis unit (40) is configured to be delivered to an inlet of the PSA unit (70).

11. The plant (100) according to any one of the preceding claims, being a synthesis gas plant, The first electrolysis feed (9) is a water-rich feed The first electrolysis unit (40) is configured to electrolyze a first electrolysis feed (9) into a cathode product gas stream (45), wherein the cathode product gas stream (45) is a synthesis gas product stream (43), Furthermore, at least a portion (41b) of the mixed gas flow (41) from the first electrolysis unit (40) is configured to be delivered to the reforming section (10) as at least a portion of the oxygen-rich feed (4).

12. The apparatus according to claim 11, wherein the first electrolysis feed (9) comprises a CO 2 The first CO-rich removal section (30) 2 A second portion (32b) of stream (32).

13. The apparatus according to any one of claims 11 to 12, wherein the first electrolysis feed (9) comprises a CO 2 The second CO-rich separation unit (60) 2 At least a portion of the flow (61).

14. The apparatus according to any one of claims 11 to 13, wherein the first electrolysis feed (9) is CO-rich 2 feed, and also contains water.

15. The device (100) according to any one of the preceding claims, further comprising: include: a second electrolysis unit (140); Of which from CO 2 The first CO-rich removal section (30) 2 A second portion (32b) of the stream (32) is configured to be supplied as an electrolysis feed to a second electrolysis unit (140), The second electrolysis unit (140) is configured to convert the first CO-rich 2 a second portion (32b) of the stream (32) is electrolyzed into an oxygen product gas and a CO-containing stream (142); Of which from CO 2 The first CO-rich removal section (30) 2 The third portion (32c) of the stream (32) is configured to be supplied to the anode of the second electrolysis unit (140) as a purge gas for the oxygen product gas, thereby outputting a first mixed gas stream (141) containing carbon dioxide and oxygen from the second electrolysis unit (140).

16. The apparatus (100) according to claim 15, wherein the water feed (8) is arranged to be mixed with the first CO-rich 2 A second portion (32b) of the stream (32) is mixed.

17. The apparatus (100) according to any one of the preceding claims, wherein the first and second electrolysis units (40, 140) comprise one or more solid oxide electrolysis cells (SOECs).

18. A method for producing hydrogen and / or synthesis gas in a plant (100) according to any one of claims 1 to 17, the method The following steps are involved: - providing an apparatus according to any one of claims 1 to 18; - conveying a mixed feed (3) of steam (2) and hydrocarbons (1) and an oxygen-rich feed (4) to a reforming section (10) comprising an autothermal reformer to provide a first synthesis gas stream (11); - The first synthesis gas stream (11) is conveyed to the CO 2 The removal section (30) is used to provide a first hydrogen-rich stream (31) and a first CO-rich stream (32). 2 stream (32); - conveying a first electrolysis feed (9) to a first electrolysis unit (40) and electrolyzing it into at least an oxygen product gas and a cathode product gas stream (45); - will come from CO 2 The first CO-rich removal section (30) 2 At least a first portion (32a) of the stream (32) is supplied to an anode of a first electrolysis unit (40) as a purge gas for the oxygen product gas, and a first mixed gas stream (41) comprising carbon dioxide and oxygen is output from the electrolysis unit (40); - Optionally, the device comprises a first water removal stage (50) and a CO 2 In the case of the separation unit (60), O delivering at least a portion (41a) of the first mixed gas stream (41) from the first electrolysis unit (40) to a first water removal stage (50) to provide at least a first water-rich stream (51) and a second mixed gas stream (52); and O At least a portion (52a) of the second mixed gas stream (52) from the first water removal stage (50) is passed to the CO 2 A separation unit (60) to provide at least a second CO-rich 2 flow (61) and an oxygen-enriched flow (62); The method comprises the additional step of conveying one or more streams selected from the following as at least a part of the oxygen-rich feed (4) to the reforming section (10): O at least a portion (41b) of the mixed gas flow (41) from the first electrolysis unit (40), O the second portion (52b) of the second mixed gas stream (52), if present, and O If present, at least a portion of the oxygen-enriched stream (62).

19. A method for producing hydrogen in a hydrogen production plant (100) according to any one of claims 4-10 and 15-17, the method The following steps are involved: - Providing a hydrogen production device (100) according to any one of claims 4-10 and 16-18; - conveying a mixed feed (3) of steam (2) and hydrocarbons (1) and an oxygen-rich feed (4) to a reforming section (10) comprising an autothermal reformer to provide a first synthesis gas stream (11); - conveying the first synthesis gas stream (11) from the reforming section (10) to the shift section (20) to provide a shifted first synthesis gas stream (11a) and providing it to the CO 2 Remove segment (30); - conveying the shifted first synthesis gas stream (11a) to the CO 2 The removal section (30) is used to provide a first hydrogen-rich stream (31) and a first CO-rich stream (32). 2 stream (32); - conveying a first electrolysis feed (9), which is a water-rich feed, to a first electrolysis unit (40) and electrolyzing it into at least an oxygen product gas and a cathode product gas stream (45), the cathode product gas stream (45) being a hydrogen-rich product stream (42); - will come from CO 2 The first CO-rich removal section (30) 2 At least a first portion (32a) of the stream (32) is supplied to an anode of a first electrolysis unit (40) as a purge gas for the oxygen product gas, and a first mixed gas stream (41) comprising carbon dioxide and oxygen is output from the electrolysis unit (40); - conveying at least a portion (41a) of the first mixed gas stream (41) from the first electrolysis unit (40) to a first water removal stage (50) to provide at least a first water-rich stream (51) and a second mixed gas stream (52); and - conveying at least a portion (52a) of the second mixed gas stream (52) from the first water removal stage (50) to the CO 2 A separation unit (60) to provide at least a second CO-rich 2 flow (61) and an oxygen-enriched flow (62); The method comprises the additional step of conveying at least a portion of the oxygen-rich stream (62) as at least a portion of the oxygen-rich feed (4) to a reforming section (10).

20. A method for producing synthesis gas in a synthesis gas plant (100) according to any one of claims 11 to 17, the method The following steps are involved: - Providing a synthesis gas plant (100) according to any one of claims 11 to 18; - conveying a mixed feed (3) of steam (2) and hydrocarbons (1) and an oxygen-rich feed (4) to a reforming section (10) comprising an autothermal reformer to provide a first synthesis gas stream (11); - conveying the first synthesis gas stream (11) from the reforming section (10) to the shift section (20) to provide a shifted first synthesis gas stream (11a) and providing it to the CO 2 Remove segment (30); - conveying the shifted first synthesis gas stream (11a) to the CO 2 The removal section (30) is used to provide a first hydrogen-rich stream (31) and a first CO-rich stream (32). 2 stream (32); - conveying a first electrolysis feed (9), which is a water-rich feed, to a first electrolysis unit (40) and electrolyzing it into at least an oxygen product gas and a cathode product gas stream (45), the cathode product gas stream (45) being a synthesis gas product stream (43); - will come from CO 2 The first CO-rich removal section (30) 2 at least a first portion (32a) of the stream (32) is conveyed to the anode of a first electrolysis unit (40) as a purge gas for the oxygen product gas, and a first mixed gas stream (41) comprising carbon dioxide and oxygen is output from the electrolysis unit (40); - conveying at least a portion (41a) of the first mixed gas flow (41) from the first electrolysis unit (40) as at least a portion of the oxygen-rich feed (4) to the reforming section (10).

21. The method according to claim 20, further comprising: The following steps are involved: From CO 2 The first CO-rich removal section (30) 2 A second portion (32b) of the stream (32) is conveyed to a first electrolysis unit (40) as at least a portion of the first electrolysis feed (9).

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