System for treating gases containing carbon dioxide

Abstract

The present invention relates to a system (1) for treating exhaust gases containing carbon dioxide, the system (1) comprising a liquefied natural gas storage tank (10), a distribution line (13) connecting the storage tank (10) to a connection terminal (11), a reforming unit (2) comprising a combustion device (6) emitting the exhaust gases containing carbon dioxide, a carbon dioxide capture unit (50) comprising at least one desublimation device (58, 58A, 58B), and a fluid loop (64) extending between the distribution line (13) and the desublimation device (58, 58A, 58B).

Description

[0001] DESCRIPTION

[0002] Title: Carbon Dioxide-Laden Gas Treatment System

[0003] The present invention relates to the field of gases emitted by consumers, and more particularly to the methods implemented to treat such gases.

[0004] When a source of carbon dioxide (CO2) emissions is in operation, carbon dioxide-laden gases are generated. These gases are generally released into the atmosphere, causing environmental damage, particularly due to their carbon dioxide content. It is therefore advisable to treat the carbon dioxide-laden gases from an emission source in order to extract the carbon dioxide for later use or commercialization.

[0005] The emission source is, for example, a reforming unit consisting of a combustion section and a reforming section, both of which emit gases laden with carbon dioxide. The reforming unit is notably used in applications for producing dihydrogen from natural gas, for example, in steam methane reforming (SMR). In the absence of carbon dioxide capture during these applications, the hydrogen produced is called "grey hydrogen." To reduce the carbon footprint of such dihydrogen production, it is known to capture the carbon dioxide from the gases emitted by the reforming section; this is then referred to as "blue hydrogen."

[0006] In addition to the reforming part, it is also possible to focus on capturing carbon dioxide from the gases emitted by the combustion part in order to further reduce the carbon footprint of the emission source.

[0007] The present invention falls within this context by proposing a system for treating gases emitted by the combustion part of a reforming unit, by capturing the carbon dioxide contained in these gases using liquefied natural gas.The present invention thus has as its main object a system for treating exhaust gases laden with carbon dioxide, comprising a liquefied natural gas storage tank, a distribution line configured to connect the storage tank to a connection terminal, the treatment system comprising a reforming unit including a combustion device emitting the exhaust gases laden with carbon dioxide and a reforming device, the treatment system comprising at least one carbon dioxide capture unit including at least one desublimation device, the treatment system comprising a fluid loop extending between the distribution line and the desublimation device, the fluid loop being configured to exchange heat between the exhaust gases laden with carbon dioxide circulating within the desublimation device and the liquefied natural gas circulating within the distribution line.

[0008] The treatment system according to the invention enables the capture of carbon dioxide present in exhaust gases emitted by a combustion device integrated into a reforming unit, as opposed to gases emitted by a reforming device also integrated into this reforming unit. The combustion device and the reforming device are two distinct sub-assemblies, the assembly forming the reforming unit.

[0009] The treatment system allows the production of blue dihydrogen, this dihydrogen being produced within the reforming unit during a reaction of natural gas with water vapor.

[0010] Carbon dioxide is extracted from the exhaust gases emitted by the combustion device using a carbon dioxide capture unit, here within a desublimation device for said carbon dioxide capture unit. This desublimation device is advantageously cooled indirectly using liquefied natural gas (LNG). LNG is used to cool a fluid loop that captures the carbon dioxide within the desublimation device. Using a fluid loop allows for the easy transfer of the LNG's cooling capacity to the desublimation device. Furthermore, managing the temperature generated by this loop within the desublimation device is simpler. Finally, the fluid loop provides a supply of fluid at the appropriate temperature when the treatment system is started up.The fluid is, for example, a heat transfer fluid in a liquid state, at every point in the fluid loop.

[0011] The storage tank constitutes a reserve of liquefied natural gas (LNG) available to supply a connection terminal. This connection terminal allows the LNG to be transformed from its liquid to its gaseous state for injection into a distribution network. The presence of a connection terminal implies the availability of LNG. The treatment system according to the invention uses the LNG as a cooling source to help desublimate the carbon dioxide present in the exhaust gases emitted by the combustion device, while simultaneously heating the LNG to prepare it for its transformation into a gaseous state for distribution to the connection terminal.

[0012] According to an optional feature of the invention, the treatment system comprises a compression unit and a drying unit, the drying unit being disposed between the compression unit and the carbon dioxide capture unit.

[0013] In other words, at the outlet of the reforming unit's combustion device, the compression unit, the drying unit, and the carbon dioxide capture unit are arranged in that order within the treatment system, so that the carbon dioxide-laden exhaust gases emitted by the reforming unit pass through them successively. The treatment system may also include additional devices that contribute to drying the carbon dioxide-laden exhaust gases emitted by the combustion device.

[0014] Having the drying unit after the compression unit improves the drying unit's performance because compressing the carbon dioxide-laden exhaust gases increases the partial pressure of the water present within them. The higher the water pressure, the smaller the drying unit can be. Positioning the carbon dioxide capture unit after the drying unit also reduces the risk of water freezing in the carbon dioxide-laden gases within a pre-cooling device in the carbon dioxide capture unit. Furthermore, this limits the amount of residual water that freezes with the carbon dioxide; otherwise, the carbon dioxide would be captured with more water than desired.

[0015] According to an optional feature of the invention, the fluid loop includes a heat exchanger, one layer of which is formed by the distribution line.

[0016] The heat exchanger is a thermal regulation device. Thanks to this heat exchanger, the desublimation unit is indirectly cooled by liquefied natural gas (LNG). More precisely, within the heat exchanger connected to the distribution line, the LNG exchanges heat with a fluid channeled in the intermediate fluid loop. This fluid then exchanges heat with the carbon dioxide-laden exhaust gases within the desublimation unit. The fluid in the fluid loop is thus cooled by the LNG and heated by the carbon dioxide-laden exhaust gases.

[0017] According to an optional feature of the invention, the processing system includes a natural gas supply line to the reforming unit, the supply line connecting the distribution line to the reforming unit.

[0018] The feed line is connected here to the distribution line between the storage tank and the connection terminal. Natural gas is used both to supply the reforming unit and to capture carbon dioxide. Specifically, the liquefied natural gas (LNG) that flows through the feed line to the reforming unit is first used to cool the fluid loop. Connecting the feed line to the distribution line allows the LNG to be used as a cooling source to help desublimate the carbon dioxide, while simultaneously heating the LNG to prepare it for use as fuel within the reforming unit.According to an optional feature of the invention, the carbon dioxide capture unit includes a means for heating the desublimation device and a carbon dioxide storage tank in liquid form connected to the desublimation device.

[0019] The heating system recovers carbon dioxide in liquid form, which was previously in solid form due to desublimation. The storage tank allows for the storage of carbon dioxide in liquid form at a pressure, for example, between 7 and 15 bar. The carbon dioxide is stored in the tank prior to being exported to a permanent storage site.

[0020] According to an optional feature of the invention, the carbon dioxide capture unit includes a pre-cooling device.

[0021] The pre-cooling device allows the temperature of the carbon dioxide-laden gases to be adjusted before they pass through the desublimation unit. The pre-cooling device is therefore positioned between the drying unit and the desublimation unit.

[0022] According to an optional feature of the invention, the pre-cooling device includes at least one primary pass configured for the circulation of exhaust gases loaded with carbon dioxide and a secondary pass configured for the circulation of decarbonized exhaust gases.

[0023] The primary pass of the pre-cooling device is located upstream of the desublimation device, while its secondary pass is downstream. Within the pre-cooling device, the decarbonized exhaust gases are therefore used to cool the exhaust gases laden with carbon dioxide.

[0024] According to an optional feature of the invention, the treatment system includes a decarbonized exhaust gas evacuation line at the outlet of the desublimation device. The evacuation line allows the decarbonized exhaust gases to be evacuated from the treatment system, for example by releasing them into the atmosphere.

[0025] According to an optional feature of the invention, the decarbonized exhaust gas evacuation line forms the secondary pass of the pre-cooling device.

[0026] This allows the use of decarbonized exhaust gases as a source of cold in the pre-cooling device prior to the evacuation of decarbonized exhaust gases from the treatment system.

[0027] According to an optional feature of the invention, the decarbonized exhaust gas evacuation line includes a pressure-reducing device.

[0028] The expansion device is used to reduce the carbon-free exhaust gases to atmospheric pressure before they are released into the atmosphere. Depending on the embodiment, the expansion device can be a valve or a turbine. When the expansion device is a turbine, it recovers energy for the compression process carried out within the compression unit.

[0029] According to an optional feature of the invention, the treatment system includes a heat exchanger disposed between the combustion device of the reforming unit and the compression unit, the decarbonized exhaust gas discharge line forming one of the passes of the heat exchanger.

[0030] The heat exchanger comprises a first pass configured to channel exhaust gases laden with carbon dioxide and a second pass configured to channel decarbonized exhaust gases. The exhaust line incorporates the second pass of the heat exchanger; thus, the heat exchanger is designed to cool the exhaust gases laden with carbon dioxide by exchanging heat with the decarbonized exhaust gases flowing through the exhaust line.

[0031] The invention further relates to a dihydrogen production installation, comprising the treatment system as previously mentioned and a connection terminal, the distribution line of the treatment system being connected to the connection terminal.

[0032] Other features, details and advantages of the invention will become clearer from the following description on the one hand, and from examples of embodiment given by way of indication and not limitation with reference to the attached drawings on the other hand, on which: [Fig. 1] illustrates, schematically, a treatment system according to the invention, in which a desublimation device is cooled by a fluid loop exchanging heat with liquefied natural gas in order to capture the carbon dioxide present in exhaust gases emitted by a combustion device of a reforming unit.

[0033] The features, variations, and different embodiments of the invention can be combined in various ways, provided they are not incompatible or mutually exclusive. In particular, variations of the invention may include only a selection of features, described hereafter in isolation from the other features described, if this selection of features is sufficient to confer a technical advantage and / or to differentiate the invention from prior art.

[0034] In the figures, elements common to several figures retain the same reference. Figure 1 thus schematically illustrates a dihydrogen production plant used in the production of so-called "blue hydrogen," that is, hydrogen that captures carbon dioxide during the dihydrogen production process. To this end, the dihydrogen production plant includes a carbon dioxide-laden gas treatment system (1).

[0035] The treatment system 1 includes a reforming unit 2, for example, a steam reforming unit for methane. The reforming unit 2 consists of at least one combustion device 4, or combustion chamber, and a reforming device 6, or reforming reactor. The reforming unit 2 is configured to form, from fuel, a gas stream containing, among other things, carbon dioxide. The fuels used to power the reforming unit 2 are natural gas and steam. To supply the reforming unit 2 with water and air, the treatment system 1 includes a water supply line 8 and an air supply line 9. The water supply line 8 is specifically configured to supply the reforming device 6, while the air supply line 9 is configured to supply the combustion device 4.To supply the reforming unit 2 with natural gas, the treatment system 1 includes a liquefied natural gas storage tank 10. The storage tank 10 is connected to a connection terminal 11 of the hydrogen production plant via a distribution line 13.

[0036] The storage tank 10 is connected to the reforming unit 2 by a supply line 12, which allows the liquefied natural gas to be channeled from the storage tank 10 to the reforming unit 2. The supply line 12 is here connected to the distribution line 13 extending to the connection terminal 11, between the storage tank 10 and this connection terminal 11.

[0037] The reforming unit 2 uses natural gas in vapor form as fuel. The distribution line 13 carries, between the storage tank 10 and a connection point of the supply line 12, a pump 14, a thermal control device 15, and a vaporization device 16. The pump 14 facilitates the extraction of the liquefied natural gas from the storage tank 10. The thermal control device 15 is a heat exchanger configured, in particular, to preheat the liquefied natural gas before its delivery to the reforming unit 2, according to an operating mode that will be described later. The thermal control device 15 also prepares the liquefied natural gas for its passage through the vaporization device 16. This vaporization device 16 is configured to vaporize the liquefied natural gas preheated in the thermal control device 15 before its use, for example, with seawater.The vaporization device 16 allows, on the one hand, the vaporization of the liquefied natural gas prior to its delivery to the reforming unit 2, and on the other hand, the vaporization prior to its arrival within the connection terminal 11. The pump 14, the thermal regulation device 15 and the vaporization device 16 are arranged in that order on the supply line 12 between the storage tank 10 and the connection point of the supply line 12.

[0038] As can be seen in Figure 1, the combustion device 4 and the reforming device 6 are supplied separately with natural gas that has been vaporized within the vaporization device 16. Thus, downstream of its connection point to the distribution line 13, the supply line 12 is split into a first branch 18 dedicated to supplying the combustion device 4 and a second branch 20 dedicated to supplying the reforming device 6. The first branch 18 and the second branch 20 extend in parallel within the treatment system 1. The first branch 18 and the second branch 20 can be equipped with valves in order to regulate the flow of the natural gas that they channel.

[0039] Within reforming unit 2, a chemical reaction between natural gas from storage tank 10 and water from water supply line 8 leads to the production of dihydrogen from reforming unit 6. A chemical reaction between natural gas from storage tank 10 and air from air supply line 9 leads to gas combustion. The production of dihydrogen induces the emission, by combustion unit 4 of reforming unit 2, of exhaust gases laden with carbon dioxide. The treatment system 1 according to the invention is designed to treat these exhaust gases in order to extract the carbon dioxide.

[0040] To this end, the treatment system 1 includes, at the outlet of the combustion device 4 of the reforming unit 2, a heat exchanger 24. The heat exchanger 24 is configured to cool the exhaust gases laden with carbon dioxide. To achieve this, the heat exchanger 24 comprises a first pass 26 configured to channel the exhaust gases laden with carbon dioxide, and a second pass 28 configured to exchange heat with the first pass 26, which will be described subsequently. The heat exchanger 24 is, for example, configured to cool the exhaust gases laden with carbon dioxide to a temperature of 55 °C. At the outlet of the heat exchanger 24, the treatment system 1 includes a cooling device 30. It is understood that the heat exchanger 24 is located between the reforming unit 2 and this cooling device 30.The cooling device 30, like the heat exchanger 24, is configured to cool the exhaust gases laden with carbon dioxide. Specifically, the cooling device 30 uses air or water to cool these exhaust gases to ambient temperature. For example, the cooling device 30 is configured to cool the exhaust gases laden with carbon dioxide to a temperature of 43 °C. The cooling device 30 is configured to condense some of the water contained in the exhaust gases laden with carbon dioxide.

[0041] The cooling device 30 is, within the treatment system 1, arranged between the heat exchanger 24 and a first condensing device 32, which is a water condensing device 32. Thus, upon exiting the cooling device 30, the exhaust gases laden with carbon dioxide flow here to the first condensing device 32. The first condensing device 32 is configured to condense at least some of the water present in the exhaust gases laden with carbon dioxide; the first condensing device 32 allows, for example, the condensation of more water than the cooling device 30. The first condensing device 32 includes for this purpose a cooling means 34 which, for example, passes through a chamber of the first condensing device 32 in order to cool the water present in the exhaust gases laden with carbon dioxide for the purpose of its condensation.The first condensation device 32 allows, for example, the cooling of exhaust gases loaded with carbon dioxide to a temperature between 10 °C and 0 °C.

[0042] The condensed water in the first condensing unit 32 is separated from the carbon dioxide-laden exhaust gases in a first separator 36 of the treatment system 1. The first separator 36 is a liquid-gas separator. The first separator 36 includes a water outlet pipe 38 that allows the condensed water to be discharged from the treatment system 1.

[0043] The exhaust gases laden with carbon dioxide flow from the first separator 36 to a compression unit 40. The compression unit 40 is configured to increase the pressure of the carbon dioxide-laden exhaust gases. As shown in Figure 1, the compression unit 40 is a multi-stage compression device comprising alternating compressors 41 and heat exchangers 43. More specifically, the compression unit 40 as depicted in Figure 1 has two compressors 41 and two heat exchangers 43. The alternation between the compressors 41 and the heat exchangers 43 is such that the compression unit 40 comprises, in this order, a first compressor 41, a first heat exchanger 43, a second compressor 41, and a second heat exchanger 43.In alternative embodiments, the compression unit 40 could, however, comprise a different number of compressors 41 and heat exchangers 43.

[0044] Upon exiting the compression unit 40, the exhaust gases laden with carbon dioxide are directed to a second condensing device 42. Similar to the first condensing device 32, the second condensing device 42 is configured to condense the water present in the carbon dioxide-laden exhaust gases. For this purpose, the second condensing device 42 is equipped with a cooling means 34, which, depending on the embodiment, may be identical to or different from that of the first condensing device 32.

[0045] The treatment system 1 includes a second separator 44. This second separator 44 is configured to separate the condensed water within the second condensing unit 42 from the carbon dioxide-laden exhaust gases. The second separator 44, like the first separator 36, is a liquid-gas separator. The condensed water is discharged from the second separator 44 via a water outlet pipe 38. The second separator 44 is located between the second condensing unit 42 and a drying unit 46. In contrast to the first separator 36 and the second separator 44, which only remove a portion of the water present in the carbon dioxide-laden exhaust gases, the drying unit 46 is configured to provide carbon dioxide-laden exhaust gases free of water. In other words, the drying unit 46 is configured to deliver a dry stream of carbon dioxide-laden gases.In other words, the separator(s) perform a first drying stage while the drying unit 46 completes this water removal by carrying out a second drying stage.

[0046] The drying unit 46 includes, but is not limited to, at least one molecular sieve 48. The molecular sieve 48 is configured to retain the water present in the carbon dioxide-laden gases. The drying unit 46 may, for example, include two molecular sieves 48 operating alternately. The water is then discharged from the molecular sieve 48 and the drying unit 46 via a water outlet pipe 38 of the treatment system 1.

[0047] Alternatively, the drying unit 46 may include a membrane or a cryogenic scrubber, either as a replacement for or in combination with the molecular sieve 48.

[0048] At the outlet of the drying unit 46, the dried carbon dioxide-laden gases are directed to the carbon dioxide capture unit 50. On the treatment system 1 of figure 1, there are therefore, in this order, the compression unit 40, the drying unit 46 and the carbon dioxide capture unit 50. Here, "in this order" means that the carbon dioxide-laden exhaust gases emitted by the combustion device 4 of the reforming unit 2 pass successively through the compression unit 40, then the drying unit 46, then the carbon dioxide capture unit 50.

[0049] The carbon dioxide capture unit 50 includes a pre-cooling device 52. The pre-cooling device 52 is a heat exchanger which includes a primary pass 54 and a secondary pass 56. The primary pass 54 is configured to channel the exhaust gases charged with carbon dioxide and to cool them by heat exchange with the secondary pass 56 which will be described later.

[0050] According to the invention, the carbon dioxide capture unit 50 of the ventilation system 1 includes a desublimation device 58 configured to desublimate the carbon dioxide present in the carbon dioxide-laden gases. The desublimation device 58 is connected to the pre-cooling device 52 and disposed downstream of the latter in a direction of carbon dioxide-laden exhaust gas flow.

[0051] The desublimation device 58 includes at least one heat exchanger configured to indirectly cool carbon dioxide-laden gases using liquefied natural gas. More specifically, and as shown in Figure 1, the desublimation device 58 comprises a first desublimator 58A and a second desublimator 58B that operate alternately. The first desublimator 58A operates, for example, in a capture or defrosting mode while the second desublimator 58B operates in a regeneration or defrosting mode, and then conversely, the first desublimator 58A operates in regeneration mode while the second desublimator 58B operates in capture mode.The alternating operation of the first desublimarer 58A and the second desublimarer 58B allows continuous capture of carbon dioxide within the desublimarion device 58, the capture mode being constantly ensured by one or the other of the desublimarers 58A, 58B.

[0052] Within the desublimation device 58, the desublimator 58A, 58B comprises a chamber 60 and a thermal management pass 62. The chamber 60 of the desublimation device 58 is configured to receive gases laden with carbon dioxide. In the capture mode, this chamber 60 is cooled by heat exchange with the thermal management pass 62. Conversely, in the regeneration mode, the chamber 60 of the desublimator 58A, 58B is heated by heat exchange with the thermal management pass 62.

[0053] According to the invention, the cooling system 1 includes a fluid loop 64 that helps cool the carbon dioxide-laden gases emitted by the decompression device 4 of the reforming unit 2. This fluid loop 64 is configured to channel a heat transfer fluid that exchanges heat with the carbon dioxide-laden gases, such a fluid being, for example, butane. The fluid loop 64 extends between the distribution line 13 on one side and the desublimation device 58 on the other. More specifically, the fluid loop 64 includes the thermal management pass 62 of the desublimation device 58 when the latter is in capture mode.

[0054] The fluid loop 64 exchanges heat with the distribution line 13 via the thermal control device 15. For this purpose, the thermal control device 15 comprises a first layer 66 and a second layer 68. The first layer 66 forms a section of the distribution line 13 which channels natural gas in a liquid state from the storage tank 10. The second layer 68 is formed by a portion of the fluid loop 64 which channels the heat transfer fluid intended to exchange heat with the carbon dioxide-laden gases.

[0055] It is understood from the above that within the thermal regulation device 15, the fluid intended to exchange calories with the exhaust gases charged with carbon dioxide which circulates in the second layer 68 is cooled by exchanging calories with the liquefied natural gas which circulates in the first layer 66.

[0056] Once cooled by heat exchange with the liquefied natural gas, the fluid channeled in the fluid loop 64 circulates to the thermal management pass 62 of the desublimation device 58 in which it exchanges heat with the carbon dioxide-laden gases circulating within the enclosure 60 of the desublimator 58A, 58B operating in capture mode, thus cooling said gases in order to desublimate the carbon dioxide they contain.

[0057] It should be noted that in the desublimator 58A, 58B of the desublimation device 58 operating in regeneration mode, the thermal management pass 62 channels a thermal management fluid separate from the fluid in the fluid loop 64. This thermal management fluid is then a heating means 70 used to warm the chamber 60 of the desublimator 58A, 58B. Such heating of the chamber 60 by the heating means 70 allows the carbon dioxide that was desublimated during the operation of the capture mode to liquefy.

[0058] At the outlet of the desublimation device 58, and more specifically at the outlet of the desublimator 58A, 58B operating in regeneration mode, the carbon dioxide is in liquid form since it has been liquefied using the heating means 70. This carbon dioxide is thus stored in liquid form in a storage tank 72 of the treatment system 1. The carbon dioxide in liquid form is for example stored in the storage tank 72 at a pressure between 7 and 15 bar.

[0059] At the outlet of the desublimation device 58, and more specifically at the outlet of the desublimator 58A, 58B operating in capture mode, the charged gases emitted by the combustion device 4 of the reforming unit 2 and freed from carbon dioxide, also called decarbonized exhaust gases, are channeled within an exhaust line 74 of the treatment system 1. The exhaust line 74 is configured to release the decarbonized exhaust gases out of the treatment system 1, here by releasing them into the atmosphere.

[0060] The exhaust line 74 includes the secondary pass 36 of the pre-cooling device 32. It is understood here that prior to their evacuation from the treatment system 1, the decarbonized exhaust gases are used as a source of cold in the pre-cooling device 52, to cool the exhaust gases laden with carbon dioxide prior to their passage into the desublimation device 58. More precisely, the decarbonized exhaust gases circulating in the secondary pass 56 exchange heat with the exhaust gases laden with carbon dioxide circulating in the primary pass 54 so as to cool said gases.

[0061] As illustrated in Figure 1, the exhaust line 74 also includes the second pass 28 of the heat exchanger 24. The decarbonized exhaust gases are in fact used in this heat exchanger 24 to cool the exhaust gases laden with carbon dioxide as they exit the combustion device 4 of the reforming unit 2. The decarbonized exhaust gases circulating in the second pass 28 of the heat exchanger 24 thus exchange heat with the exhaust gases laden with carbon dioxide which are channeled in the first pass 26 of this heat exchanger 24.

[0062] At the outlet of the heat exchanger 24 on the exhaust line 74, the treatment system 1 includes a pressure reducing device 76. The pressure reducing device 76 is configured to reduce the pressure of the decarbonized exhaust gases prior to their evacuation from the treatment system 1.

[0063] The present invention thus proposes a system for treating gases charged with carbon dioxide from a combustion part of a reforming unit, the treatment system using the calorific resource of natural gas in liquid form as a cold source to achieve the capture of carbon dioxide by desublimation.

[0064] The present invention cannot, however, be limited to the means and configurations described and illustrated herein, and it also extends to all equivalent means and configurations as well as to all technically operative combinations of such means.

Claims

DEMANDS 1. A carbon dioxide-laden exhaust gas treatment system (1) comprising a liquefied natural gas storage tank (10), a distribution line (13) configured to connect the storage tank (10) to a connection terminal (11), the treatment system (1) comprising a reforming unit (2) comprising a combustion device (6) emitting the carbon dioxide-laden exhaust gases and a reforming device (6), the treatment system (1) comprising at least one carbon dioxide capture unit (50) comprising at least one desublimation device (58, 58A, 58B), the treatment system (1) comprising a fluid loop (64) extending between the distribution line (13) and the desublimation device (58, 58A, 58B), the fluid loop (64) being configured to exchange heat between the carbon dioxide-laden exhaust gases circulating within the device of desublimation (58, 58A,58B) and liquefied natural gas circulating within the distribution line (13).

2. A treatment system (1) according to claim 1, comprising a compression unit (40) and a drying unit (46), the drying unit (46) being disposed between the compression unit (40) and the carbon dioxide capture unit (50).

3. A treatment system (1) according to any one of claims 1 and 2, wherein the fluid loop (64) comprises a heat exchanger (15) of which a layer (26) is formed by the distribution line (13).

4. Processing system (1) according to any one of claims 1 to 3, comprising a natural gas supply line (12) to the reforming unit (2), the supply line (12) connecting the distribution line (13) to the reforming unit (2).

5. A treatment system (1) according to any one of claims 1 to 4, wherein the carbon dioxide capture unit (50) comprises a heating means (70) for the desublimation device (58, 58A, 58B) and a storage tank (72) for carbon dioxide in liquid form connected to the desublimation device (58, 58A, 58B).

6. A treatment system (1) according to any one of claims 1 to 5, wherein the carbon dioxide capture unit (50) comprises a pre-cooling device (52).

7. Treatment system (1) according to claim 6, wherein the pre-cooling device (52) comprises at least one primary pass (54) configured for the circulation of exhaust gases loaded with carbon dioxide and a secondary pass (56) configured for the circulation of decarbonized exhaust gases.

8. Treatment system (1) according to any one of claims 1 to 7, comprising a decarbonized exhaust gas evacuation line (74) at the outlet of the desublimation device (58, 58A, 58B).

9. A treatment system (1) according to claim 8 in combination with claim 7, wherein the decarbonized exhaust gas discharge line (74) forms the secondary pass (56) of the pre-cooling device (52).

10. A treatment system (1) according to any one of claims 1 to 9 in combination with claim 8, wherein the decarbonized exhaust gas discharge line (74) comprises an expansion device (76).

11. Processing system (1) according to any one of claims 1 to 10 in combination with claims 2 and 8, comprising a heat exchanger (24) disposed between the combustion device (6) of the reforming unit (2) and the compression unit (40), the exhaust line (74) of the decarbonized exhaust gas forming one of the passes (28) of the heat exchanger (24).

12. Hydrogen production installation, comprising the treatment system (I) according to any one of claims 1 to 11 and a connection terminal (II), the distribution line (13) of the treatment system (1) being connected to the connection terminal (11).

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