Auto-thermal reforming process for hydrogen production

Abstract

A hydrogen production apparatus and a method of producing a hydrogen stream are provided. The hydrogen production plant includes a steam superheater arranged to superheat at least a portion of the first steam stream from the steam drum to provide a superheated steam stream by heat exchange with the first shifted syngas stream. At least a first portion of the superheated steam stream is configured to heat a first stream comprising hydrocarbons, and then feed the first stream to a pre-reformer unit. In this way, the use of a flame heater or an electric heater can be reduced or avoided.

Description

Technical Field

[0001] The present invention relates to the field of hydrogen production plants and methods for producing a hydrogen gas stream. The hydrogen production plant of the present invention comprises a steam superheater, which is arranged to superheat at least a portion of a first steam stream from a steam drum, thereby providing a superheated steam stream. At least a first portion of the superheated steam stream is arranged to heat a first stream comprising hydrocarbons, which is then fed to a pre-reformer unit. Background Art

[0002] Standard process layout of hydrogen production equipment (e.g. SynCOR TM The process) generally comprises a fired heater for preheating the hydrocarbon feed to the desulfurization section, the hydrocarbon feed and steam to the pre-reformer, and the pre-reformed gas to the autothermal reformer (ATR).

[0003] Considerable effort has been invested in optimizing the production of hydrogen production equipment, with the goal of improving overall energy efficiency and reducing capital costs. The need for more cost-effective hydrogen production has driven the development of technologies and catalysts for large-scale hydrogen production units to achieve economies of scale. In addition, efforts have been made to reduce greenhouse gas emissions from such equipment.

[0004] Reducing CO2 emissions from hydrogen production equipment will have significant advantages. WO2022038089 describes an apparatus for producing a hydrogen-rich stream from a hydrocarbon feed. Other publications in this field include US11 498 834B1 and Consonni S et al. International Journal of Hydrogen Energy, 30, 7, 1 July 2005, pages 701-718.

[0005] One object of the present invention is to reduce the consumption of hydrocarbon feed and fuel in a hydrogen production plant and / or method, thereby improving energy efficiency. At the same time, one object of the present invention is to reduce CO2 emissions in a hydrogen production plant and / or method. As a result, the carbon footprint of the plant can be significantly reduced.

[0006] The present invention solves the above-referenced and other problems. Summary of the invention

[0007] It has surprisingly been found that by using only internally generated superheated steam, an improved apparatus and process can be provided wherein no fired heaters need to be used during normal operation. A significant reduction in steam output is also achieved, as is a lower steam to carbon ratio of the synthesis gas from the ATR unit. Overall, excellent economies of scale are achieved.

[0008] Therefore, a first aspect of the present invention relates to a hydrogen production device, the device comprising:

[0009] - a first stream comprising hydrocarbons;

[0010] - a second stream comprising an oxidant;

[0011] - a pre-reformer unit arranged to receive said first stream comprising hydrocarbons and to provide a pre-reformed stream;

[0012] an autothermal reforming (ATR) unit arranged to receive the pre-reformed stream and the second stream comprising an oxidant and to provide a first synthesis gas stream;

[0013] - a first waste heat boiler arranged to provide a first steam flow via a steam drum;

[0014] a hydrogen synthesis and purification section arranged to receive at least said first synthesis gas stream and to provide a hydrogen stream and at least one tail gas stream;

[0015] wherein the hydrogen synthesis and purification section comprises a high temperature shift reactor configured to receive at least a portion of the first synthesis gas stream and to provide a first shifted synthesis gas stream;

[0016] wherein the hydrogen production equipment further comprises a steam superheater, which is configured to superheat at least a portion of the first steam flow from the steam drum by exchanging heat with the first shifted synthesis gas flow from the high temperature shift reactor, thereby providing a superheated steam flow; and

[0017] The hydrogen production equipment further comprises a second heat exchanger (210), which is configured to heat the first stream (1) containing hydrocarbons by exchanging heat with at least a first portion of the superheated steam stream (62), and then feed the first stream (1) to the pre-reformer unit (30).

[0018] There is also provided a method of producing a hydrogen gas stream in a hydrogen plant as defined herein.

[0019] Further details of the technique are provided in the accompanying dependent claims, the drawings and the examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The technique is illustrated by the following schematic diagram, where:

[0021] Figure 1 The layout of the hydrogen production plant of the present invention is shown.

[0022] (1) First stream containing hydrocarbons

[0023] (1a) A heated first stream comprising hydrocarbons

[0024] (2) Second stream containing oxidant

[0025] (3) A third feed comprising hydrogen

[0026] (4)…

[0027] (5) First gas feed comprising hydrocarbons (6) Hydrocarbon feed gas comprising hydrocarbons (9) Atmospheric air (30) Pre-reformer unit (31) Pre-reformed stream (39) Air separation unit (40) Autothermal reforming (ATR) unit (41) First synthesis gas stream (42) Internal steam feed (43) Optional internal steam stream (50) High temperature shift reactor (51) First shifted synthesis gas stream (52) Cooled shifted synthesis gas stream (55) Low temperature shift reactor (60) Steam drum (61) First steam stream (62) Superheated steam stream (64) Superheated steam stream (65) Export steam (70) Hydrogenation section (71) Hydrogenation feed gas (80) Desulfurization unit (81) Desulfurized hydrogenation feed gas (90) First waste heat boiler (101) Hydrogen gas stream (102) Tail gas stream (110) Steam superheater (190) Second waste heat boiler

[0028] (210) Second heat exchanger

[0029] (220) First heat exchanger

[0030] (230)Separator

[0031] (231) Process condensate 231 (mainly comprising water)

[0032] (240)CO2 removal section

[0033] (241) CO2-rich stream

[0034] (250) Pressure Swing Adsorption (PSA) Unit

[0035] (500) Hydrogen production equipment

[0036] Detailed Description

[0037] Unless otherwise indicated, percentages of gas content are given in volume %.

[0038] For the avoidance of doubt, the term "feed" refers to means, such as pipes, pipelines, etc., for supplying the gas to the appropriate section, stage, reactor or unit.

[0039] A "stage" includes one or more "units" that change the chemical composition of a feed and may additionally include elements that do not change the chemical composition of a feed or stream, such as heat exchangers, mixers or compressors.

[0040] The term "synthesis gas" (abbreviated as "syngas") refers to a gas comprising hydrogen, carbon monoxide, carbon dioxide, steam and small amounts of other gases (such as argon, nitrogen, methane, etc.).

[0041] The present invention provides a method as described above and as Figure 1 A hydrogen production plant is shown schematically.

[0042] A first stream comprising hydrocarbons is provided. The first stream suitably comprises a majority (e.g., greater than 80%, such as greater than 90%) of methane. Higher order hydrocarbons (containing>2 carbon atoms) may also be present. The first stream suitably originates from a natural gas feed which has been pretreated, for example, by hydrogenation and desulfurization.

[0043] A second stream comprising an oxidant is also provided, which stream is suitably directed to the ATR unit. Suitably, the oxidant feed is mainly composed of oxygen. The oxidant feed of O2 is suitably "oxygen-enriched", i.e., the main part of the feed is O2; for example, more than 75%, such as more than 90% or more than 95%, such as more than 99% of the feed is O2. The oxidant feed may also contain other components, such as nitrogen, argon, CO2 and / or steam. The oxidant feed will typically contain a small amount of steam (e.g., 2-10%). The source of the oxidant feed (oxygen) may be at least one air separation unit (ASU) and / or at least one membrane unit. The source of oxygen may also be at least one electrolyzer unit. The oxidant feed of O2 may come from at least one electrolyzer, which converts steam or water into hydrogen and oxygen by using electrical energy. Steam may be added to the oxidant feed comprising oxygen upstream of the ATR section.

[0044] The pre-reformer unit is arranged to receive a first stream comprising hydrocarbons and provide a pre-reformed stream. Pre-reforming is the process of steam reforming methane and heavier hydrocarbons and methanating the reformed products of the heavier hydrocarbons. The adiabatic pre-reformer is usually located upstream of the main steam reformer and uses a catalyst with a high nickel content. Therefore, the pre-reformed stream contains CO, CO2 and CH4.

[0045] An autothermal reforming (ATR) unit is arranged to receive a pre-reformed stream (from a pre-reformer unit) and a second stream comprising an oxidant and to provide a first synthesis gas stream from these streams. An ATR unit typically comprises a burner, a combustion chamber and a catalyst bed contained within a refractory lined pressure vessel. In the ATR unit, hydrocarbons are partially combusted by a substoichiometric amount of oxygen and subsequently steam reformed in a fixed bed of a steam reforming catalyst, i.e., the reverse reaction of reactions (1) and (2) of the partially combusted hydrocarbons.

[0046]

[0047] Due to the high temperatures, a certain degree of steam reforming also occurs in the combustion chamber. The steam reforming reaction is accompanied by the water-gas shift reaction. Typically, at the reactor outlet, the gas is at or close to equilibrium with respect to steam reforming and water-gas shift reactions. More details and a complete description of ATR can be found in the prior art, for example in "Studies in Surface Science and Catalysis, Vol. 152, "Synthesis gas production for FT synthesis"; Chapter 4, p. 258-352, 2004".

[0048] Typically, the effluent gas stream from the ATR reactor, i.e., the first synthesis gas stream, has a temperature of 900-1100° C. Synthesis gas typically comprises hydrogen, carbon monoxide, carbon dioxide and steam. Other components such as methane, nitrogen and argon may also often be present in small amounts. The operating pressure of the ATR reactor is 5 to 100 bar or more, more preferably 15 to 60 bar.

[0049] The apparatus is configured such that the inlet temperature of the hydrocarbon feed to the ATR is below 650°C, such as 550°C or 500°C or lower, such as 300-400°C. The above temperatures are lower than typical ATR inlet temperatures (600-700°C), which is generally desirable in order to reduce oxygen consumption in the ATR. Therefore, the apparatus is deliberately and counterintuitively configured to have a lower ATR inlet temperature. By setting a lower ATR inlet temperature, suitably 550°C or lower, such as 500°C or lower, such as 300-400°C, the heat required in the heater unit (e.g., a fired heater) for preheating the hydrocarbons is significantly reduced, thereby enabling the use of much smaller fired heaters or a reduction in the number of fired heaters. By setting an ATR inlet temperature of 300-400°C, it is even possible to avoid the use of fired heaters altogether. Another benefit is the reduction of CO2 emissions from the fired heater.

[0050] The hydrogen plant comprises a first waste heat boiler arranged to provide a first steam flow via a steam drum. The steam drum receives steam from the first waste heat boiler and optionally a second waste heat boiler. Typically, the steam flow from the steam drum is provided in the range of 25 to 130 barg and 225 to 300°C.

[0051] The downstream section of the device is a hydrogen synthesis and purification section. The hydrogen synthesis and purification section is arranged to receive at least the first synthesis gas stream and provide a hydrogen stream and at least one tail gas stream. The hydrogen synthesis and purification section generally comprises (in order): a high temperature (HT) shift reactor, a steam superheater, a low temperature (LT) shift reactor, a second waste heat boiler, a separator, a CO2 removal section and a pressure swing adsorption (PSA) unit.

[0052] Specifically, the hydrogen synthesis and purification section comprises a high temperature (HT) shift reactor, which is arranged to receive at least a portion of the first syngas stream and provide a first shifted syngas stream. The first shifted syngas stream is provided from the HT shift reactor at a temperature ranging from 420 to 480°C.

[0053] The hydrogen production plant also includes a steam superheater (in the form of a heat exchanger). The steam superheater is arranged to superheat at least a portion of the first steam flow from the steam drum by heat exchange with the first shifted synthesis gas flow from the high temperature shift reactor, thereby providing a superheated steam flow. In this way, the first steam flow from the steam drum is heated from a temperature of 255-330°C to a temperature of 400-450°C. The steam drum is suitably arranged to receive an internal steam feed (i.e. from other parts of the same plant) or an external steam feed (i.e. from outside the plant). Preferably, the steam drum is arranged to receive an internal steam feed.

[0054] In one aspect, the hydrogen plant further comprises a first waste heat boiler (WHB). The WHB is arranged downstream of the ATR unit and is arranged to provide an internal steam feed by heat exchange with at least a portion of the first synthesis gas stream from the ATR unit. By recovering energy in this way, optimal utilization of the available energy is ensured.

[0055] The superheated steam stream can be used for various preheating procedures, thereby reducing or avoiding the use of fired or electric heaters. According to the invention, at least a first portion of the superheated steam stream is arranged to heat a first stream comprising hydrocarbons before feeding the first stream to a pre-reformer unit.

[0056] The superheated steam stream may also be arranged to heat at least a portion of the hydrocarbon feed gas provided to the plant, before the feed gas is fed to the hydrogenation section. Thus, in particular, the hydrogen plant further comprises a second heat exchanger arranged to heat the first stream comprising hydrocarbons by exchanging heat with at least a first portion of the superheated steam stream, before the first stream is fed to the pre-reformer unit.

[0057] Furthermore, at least a portion of the superheated steam stream may be arranged to heat at least a portion of a second stream comprising an oxidant, said portion of the second stream then being fed to an autothermal reforming (ATR) unit. Preferably, the heating of the second stream comprising an oxidant with the superheated steam stream is achieved by mixing the superheated steam stream with at least a portion of the second stream comprising an oxidant. The mixed stream is then fed to an autothermal reforming (ATR) unit.

[0058] The order in which the superheated steam streams are heated may also be of importance, i.e., the streams / segments with higher temperature requirements are heated first, followed by the streams / segments with lower temperature requirements. Figure 1 As shown, a first portion of the superheated steam stream is arranged to heat at least a portion of a first stream comprising hydrocarbons, which is then fed to a pre-reformer unit; subsequently, this portion of the superheated steam stream is arranged to heat at least a portion of a hydrocarbon feed gas, which is then fed to a hydrogenation section. In addition, a portion of the superheated steam stream (which may be the same portion or a different portion used to heat the first stream comprising hydrocarbons) is optionally subsequently arranged to heat at least a portion of a second stream comprising an oxidant (e.g. by mixing), which portion of the second stream is then fed to an autothermal reforming (ATR) unit. Excess superheated steam can be exported from the device.

[0059] The hydrogen production equipment may include one or more units located upstream of the pre-reformer unit. On the one hand, the hydrogen production equipment includes a desulfurization unit arranged upstream of the pre-reformer unit, and a hydrogenation section arranged upstream of the desulfurization unit. The hydrogenation section is configured to receive a hydrocarbon feed gas (provided by mixing a first hydrocarbon-containing gas feed (usually a natural gas feed) with a third feed gas (usually an internal hydrogen-rich stream) containing hydrogen) and provide a hydrogenated gas feed. The hydrogenated feed gas is configured to be fed to the desulfurization unit. The desulfurization unit is configured to receive the hydrogenated feed gas, and the desulfurized hydrogenated feed gas is provided to the pre-reformer unit as the first stream containing hydrocarbons.

[0060] It has been found that the heat that superheated steam can provide is sufficient to preheat various streams as required. Therefore, the use of heater units (such as fired heaters) can be avoided in normal operation, thereby reducing the CO2 emissions of the device. Therefore, on the one hand, the hydrogen production plant does not include any heating unit (such as a fired heater unit or an electric heater unit) configured to be used in normal operation, and the heating unit is configured to heat at least a portion of the first stream containing hydrocarbons, and then the first stream is fed to the pre-reformer unit. On the other hand, the hydrogen production plant does not include any heater unit (such as a fired heater unit or an electric heater unit) configured to be used in normal operation, and the heater unit is configured to heat the first hydrocarbon-containing gas feed. On the other hand, the hydrogen production plant does not include any heating device (such as a heater unit, such as a fired heater unit or an electric heater unit) configured to be used in normal operation, and the heating device is configured to heat the pre-reformed stream, and then the first stream is fed to the ATR unit. In fact, using the present invention, heating the pre-reformed stream between the pre-reformer unit and the ATR unit can be completely avoided during normal operation. During startup or shutdown, one or more heater units can be used to heat various streams.

[0061] The superheated steam stream may also be used to heat the pre-reformer.In this aspect, at least a portion of the superheated steam is arranged to mix with the first stream comprising hydrocarbons upstream of the inlet of the pre-reformer unit.

[0062] The superheated steam stream may also be used to heat the first syngas stream downstream of the first waste heat boiler. In this aspect, at least a portion of the superheated steam is arranged to mix with the first syngas stream downstream of the first waste heat boiler.

[0063] The hydrogen production plant may further optionally include a second waste heat boiler arranged downstream of the steam superheater. The second waste heat boiler is arranged to recover heat from the first shifted synthesis gas stream to provide additional steam for the steam drum.

[0064] A method for producing a hydrogen gas stream in a hydrogen production plant according to the present invention is also provided. Generally speaking, the method comprises the following steps:

[0065] - Providing a hydrogen production plant according to any one of the preceding claims;

[0066] - feeding at least a first part of the first stream comprising hydrocarbons to a pre-reformer unit and providing a pre-reformed stream;

[0067] - feeding the pre-reformed stream and the second stream comprising the oxidant to an autothermal reforming unit and providing a first synthesis gas stream;

[0068] - providing a first steam stream from a first waste heat boiler via a steam drum;

[0069] - Feeding at least part of the first synthesis gas stream to a hydrogen synthesis and purification section and providing a hydrogen stream and at least one tail gas stream.

[0070] The hydrogen synthesis and purification section comprises a high temperature shift reactor, so that the method comprises the following additional steps:

[0071] - feeding at least a portion of the first synthesis gas stream to the high temperature shift reactor and providing a first shifted synthesis gas stream;

[0072] - superheating at least a portion of the first steam stream from the steam drum by heat exchange with the first shifted synthesis gas stream in a steam superheater to provide a superheated steam stream; and

[0073] - At least a portion of said first stream (1) comprising hydrocarbons is heated in said second heat exchanger (210) by heat exchange with a superheated steam stream (62) before said first stream (1) is fed to a pre-reformer unit (30).

[0074] All details of the apparatus presented above also apply mutatis mutandis to the method of the invention.

[0075] Suitably, the first stream is heated at the inlet of the pre-reformer unit to a temperature of 440° C. or less, preferably 410° C. or less, more preferably 350-400° C. The method may further comprise the step of adding at least a portion of the superheated steam stream to at least a portion of the second stream comprising the oxidant, thereby reaching a temperature of, for example, 350° C. or more, and then feeding the mixed stream to the ATR unit.

[0076] In a specific aspect, the hydrogen production equipment includes a desulfurization unit disposed upstream of a pre-reformer unit and a hydrogenation section disposed upstream of the desulfurization unit, the hydrogenation section being configured to receive a hydrocarbon-containing feed gas and provide a hydrogenated feed gas, the hydrogenated feed gas being configured to be fed to the desulfurization unit, and the desulfurization unit being configured to receive the hydrogenated feed gas and provide the desulfurized hydrogenated feed gas to the pre-reformer unit as the first stream containing hydrocarbons; the method may further include the following steps:

[0077] - Heating at least a portion of the hydrocarbon feed gas with a superheated steam stream, preferably to a temperature of 350° C. or higher, before feeding the feed gas to the hydrogenation section.

[0078] The purification section partially or completely removes CO2, CO, CH4, H2O, N2 and Ar (but not limited to these) components in the shifted synthesis gas. Therefore, this section may include one or more of the following steps: amine washing, cryogenic separation, pressure swing adsorption and methanation. DETAILED DESCRIPTION

[0079] The following provides Figure 1 , which shows a hydrogen production plant 500, which includes a hydrogen synthesis and purification section 100. A first hydrocarbon-containing gas feed 5 (e.g., a natural gas feed) is mixed with a hydrogen feed 3 to provide a combined hydrocarbon feed gas 6, which is preheated to about 380°C by a first heat exchanger 220, the required heat being provided by a superheated steam stream 62. The heated combined feed gas 6 is sent to a hydrogenation section 70, where a hydrogenated feed gas 71 is formed, which is then sent to a desulfurization unit 80 to provide a desulfurized hydrogenated feed gas 81 (i.e., a first stream 1 comprising hydrocarbons). The first stream 1 comprising hydrocarbons is heated in a second heat exchanger 210 (e.g., heated to a temperature of about 400°C), the required heat also being provided by a superheated steam stream 62, and then fed to a pre-reformer unit 30 as a heated first stream 1.

[0080] In order to provide the required heating effect, the superheated steam stream is first used to heat the first stream 1 and subsequently used to heat the first hydrocarbon-containing gas feed 5, as shown.

[0081] Atmospheric air 9 is separated in air separation unit 39 to provide oxygen feed (i.e. oxidant feed 2). Oxygen feed 2 is optionally heated in a steam condenser (not shown) and mixed with a portion of (cooled) superheated steam stream 62 before being fed to ATR unit 40.

[0082] In the ATR unit 40, the heated first stream 1 reacts with the oxygen feed to provide a first synthesis gas stream 41. The first waste heat boiler 90 is disposed downstream of the ATR unit 40 and provides an internal steam feed 42 to the steam drum 60 by heat exchange between the boiler water stream from the steam drum 60 and the first synthesis gas stream 41 from the ATR unit 40.

[0083] The steam drum 60 is arranged to dry the steam by separating the liquid water and to provide, as required, a first steam flow 61. The steam drum is supplied with boiler feed water (not shown) corresponding to the steam production and boiler water discharge (not shown).

[0084] In the embodiment shown, a portion of the superheated steam stream will also be mixed with the first syngas stream 41 downstream of the first waste heat boiler. The high temperature (HT) shift reactor 50 receives the first syngas stream 41 downstream of the first waste heat boiler 90 and provides a first shifted syngas stream 51. The steam superheater 110 is arranged downstream of the HT shift reactor and superheats the first steam stream 61 from the steam drum 60 by heat exchange with the first shifted syngas stream 51 from the HT shift reactor 50. A superheated steam stream 62 is thereby generated, which is used in other parts of the device 500, as previously described.

[0085] Downstream of the superheater 110, the shifted synthesis gas stream is then fed to a low temperature (LT) shift reactor 55 for further shifting. As shown in the figure, a second waste heat boiler 190 is located between the HT shift reactor and the LT shift reactor, and generates a second internal steam feed 43 for the steam drum 60 by heat exchange with the cooled shifted synthesis gas stream 52 downstream of the steam superheater 110 through the boiler water flow from the steam drum 60.

[0086] After LT shift, the product gas is sent to separator 230, where process condensate 231 (mainly containing water) is removed. The product gas is then sent to CO2 removal section 240, where CO2 is removed in the form of CO2-rich stream 241. The product gas is then sent to pressure swing adsorption (PSA) unit 250 to separate hydrogen stream 101 and exhaust gas stream 102, which can be output as fuel.

[0087] Example 1

[0088] according to Figure 1 Energy and mass balance calculations were performed, and the main results are shown in Table 1 below:

[0089] NG feed flow rate (#5) Nm3 / h 85420 <![CDATA[H2 production (#101)]]> Nm3 / h 200000 Steam / carbon ratio upstream of pre-reformer (#30) mol / mol 0.52 Total Steam Generation (#61) kg / h 205069 Steam heater duty upstream of pre-reformer (#210) Gcal / h 1.85 NG heater duty upstream of hydrogenator (#220) Gcal / h 12.8 Hydrogenator inlet temperature (#70) ℃ 380 Pre-reformer inlet temperature (#30) ℃ 407

[0090] The present invention has been described with reference to several aspects and drawings. However, a person skilled in the art will be able to select and combine various aspects within the scope of the present invention, which scope is defined by the appended claims. All documents mentioned herein are incorporated herein by reference.

Claims

1. A hydrogen production device (500), the device (500) comprising: - a first stream (1) comprising hydrocarbons; - a second stream (2) comprising an oxidizing agent; - a pre-reformer unit (30) arranged to receive said first stream (1) comprising hydrocarbons and to provide a pre-reformed stream (31); - an autothermal reforming (ATR) unit (40) arranged to receive the pre-reformed stream (31) and the second stream (2) comprising an oxidant and to provide a first synthesis gas stream (41); - a first waste heat boiler (90) arranged to provide a first steam flow (61) via a steam drum (60); a hydrogen synthesis and purification section (100) arranged to receive at least the first synthesis gas stream (41) and to provide a hydrogen gas stream (101) and at least one tail gas stream (102); The hydrogen synthesis and purification section (100) comprises a high temperature shift reactor (50) configured to receive at least a portion of the first synthesis gas stream (41) and provide a first shifted synthesis gas stream (51); The hydrogen production equipment further comprises a steam superheater (110) configured to superheat at least a portion of the first steam flow (61) from the steam drum (60) by heat exchange with the first shifted synthesis gas flow (51) from the high temperature shift reactor (50), thereby providing a superheated steam flow (62); and The hydrogen production equipment further comprises a second heat exchanger (210), which is configured to heat the first stream (1) containing hydrocarbons by exchanging heat with at least a first portion of the superheated steam stream (62), and then feed the first stream (1) to the pre-reformer unit (30).

2. The hydrogen production equipment according to claim 1, wherein the steam drum (60) is configured to receive an internal steam feed (42) and an optional internal steam flow (43) or an external steam feed; preferably wherein the steam drum (60) is configured to receive only an internal steam feed.

3. The hydrogen production equipment according to claim 2 also includes a first waste heat boiler (90) arranged downstream of the ATR unit (40), and the waste heat boiler (90) is configured to provide the internal steam feed (42) by heat exchange with at least a portion of the first synthesis gas flow (41) from the ATR unit (40).

4. The hydrogen production equipment according to any of the preceding claims, further comprising a second waste heat boiler (190) arranged downstream of the steam superheater (110), wherein the waste heat boiler (190) is arranged to provide the internal steam feed (43) by heat exchange with at least a portion of the synthesis gas flow (52) from the steam superheater (110).

5. A hydrogen production plant according to any of the preceding claims, wherein at least a portion (64) of the superheated steam flow is mixed with the second flow (2) comprising the oxidant before the second flow (2) is fed to the autothermal reforming (ATR) unit (40).

6. A hydrogen production device according to any one of the preceding claims, wherein the hydrogen production device comprises a desulfurization unit (80) arranged upstream of the pre-reformer unit (30), and a hydrogenation section (70) arranged upstream of the desulfurization unit (80), the hydrogenation section (70) being arranged to receive a hydrocarbon feed gas (6) and to provide a hydrogenation gas feed (71), the hydrogenation gas feed (71) being arranged to be fed to the desulfurization unit (80); and wherein the desulfurization unit (80) is arranged to receive the hydrogenation feed gas (71) and to provide the desulfurized hydrogenation feed gas (81) as a first stream (1) containing hydrocarbons to the pre-reformer unit (30).

7. The hydrogen plant according to claim 6, wherein the superheated steam flow (62) is arranged to heat at least a portion of the hydrocarbon feed gas (6) before feeding the feed gas (6) to the hydrogenation section (70).

8. A hydrogen production device according to any one of claims 5-6, wherein at least a first portion of the superheated steam flow (62) is configured to heat at least a portion of the first flow (1) containing hydrocarbons, and then the first flow (1) is fed to a pre-reformer unit (30); and wherein the first portion of the superheated steam flow (62) is subsequently configured to heat at least a portion of a hydrocarbon feed gas (6), and then the hydrocarbon feed gas (6) is fed to a hydrogenation section (70); and wherein optionally, at least a portion (64) of the cooled superheated steam flow is subsequently configured to be mixed with at least a portion of a second flow (2) containing an oxidant, and then the portion of the second flow (2) is fed to an autothermal reforming (ATR) unit (40).

9. The hydrogen production plant according to claim 8, wherein the hydrocarbon feed gas (6) is a mixture of a third feed (3) comprising hydrogen and a first hydrocarbon gas feed (5).

10. The hydrogen production plant according to claim 9, wherein the first hydrocarbon-containing gas feed (5) is a natural gas feed.

11. A hydrogen production device according to any of the preceding claims, wherein the hydrogen production device does not include any heater unit arranged to be used in normal operation, such as a fired heater unit or an electric heater unit, which is arranged to heat at least a portion of the first stream (1, 1a) containing hydrocarbons before feeding the first stream (1) to a pre-reformer unit (30).

12. The hydrogen plant according to any one of the preceding claims, wherein the hydrogen plant does not comprise any heater unit used in normal operation, such as a fired heater unit or an electric heater unit, which is arranged to heat the first hydrocarbon-containing gas feed (5).

13. The hydrogen plant according to any of the preceding claims, wherein the hydrogen plant does not comprise any heating means used in normal operation, such as a heater unit, the heating means being arranged between the pre-reformer unit (30) and the ATR unit (40).

14. A hydrogen plant according to any one of the preceding claims, wherein at least a portion of the superheated steam (62) is arranged to mix with the first stream (1) comprising hydrocarbons upstream of the inlet of the pre-reformer unit (30).

15. A method for producing a hydrogen gas stream (101) in a hydrogen production plant (500) according to any one of the preceding claims, the method comprising the following steps: - Providing a hydrogen production plant according to any one of the preceding claims; - feeding at least a first part of the first stream (1) comprising hydrocarbons to a pre-reformer unit (30) and providing a pre-reformed stream (31); - feeding the pre-reformed stream (31) and the second stream (2) comprising the oxidant to an autothermal reforming (ATR) unit (40) and providing a first synthesis gas stream (41); - providing a first steam flow (61) from a first waste heat boiler (90) via a steam drum (60); - feeding at least a portion of the first synthesis gas stream (41) to a hydrogen synthesis and purification section (100) and providing a hydrogen gas stream (101) and at least one tail gas stream (102); The hydrogen synthesis and purification section (100) comprises a high temperature shift reactor (50), so that the method comprises the following additional steps: - feeding at least a first portion of the first synthesis gas stream (41) to the high temperature shift reactor (50) and providing a first shifted synthesis gas stream (51); - superheating at least a portion of the first steam stream (61) from the steam drum (60) by heat exchange with the first shifted synthesis gas stream (51) in a steam superheater (110) to provide a superheated steam stream (62); as well as - Heating at least a portion of said first stream (1) comprising hydrocarbons in said second heat exchanger (210) by heat exchange with said superheated steam stream (62) and then feeding said first stream (1) to a pre-reformer unit (30).

16. The method according to claim 15, wherein the first stream (1) is heated to a temperature of 440°C or less, preferably 410°C or less, more preferably 350-400°C at the inlet of the pre-reformer unit (30).

17. The method according to any one of claims 15-16, further comprising the step of mixing at least a portion (64) of the superheated steam flow with the second flow (2) comprising the oxidant before feeding the second flow (2) to the ATR unit (40).

18. The method according to any one of claims 15 to 17, wherein the hydrogen production equipment comprises a desulfurization unit (80) arranged upstream of the pre-reformer unit (30) and a hydrogenation section (70) arranged upstream of the desulfurization unit (80), the hydrogenation section (70) being arranged to receive a hydrocarbon-containing feed gas (6) and to provide a hydrogenated feed gas (71), the hydrogenated feed gas (71) being arranged to be fed to the desulfurization unit (80); and wherein the desulfurization unit (80) is arranged to receive the hydrogenated feed gas (71) and to provide the desulfurized hydrogenated feed gas (81) to the pre-reformer unit (30) as a first stream (1) containing hydrocarbons; the method further comprises the following steps: - Heating at least a portion of the hydrocarbon feed gas (6) using the superheated steam stream (62), preferably to a temperature of 350°C or higher, before feeding the feed gas (6) to the hydrogenation section (70).

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