FR3060552A1 - SYSTEM FOR GENERATING GASEOUS DIHYDROGEN - Google Patents

Abstract

The present invention relates to a system (1) for generating gaseous hydrogen, comprising at least: - a charge (3) of a hydrogen storage material, - a heating member (5) configured to heat the loading at the level of a heating zone (Z1), - a temperature sensor (7) in contact with the charge and located at a non-zero distance (di) from the heating zone, and - a control module (M) configured to controlling the heating intensity achieved by the heater according to the temperature measured by the temperature sensor.

Description

© Publication no .: 3,060,552 (to be used only for reproduction orders)

©) National registration number: 16 62861 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY

COURBEVOIE

©) Int Cl ⁸ : C 01 B 3/00 (2017.01), H 01 M 8/06, B 64 D 41/00

A1 PATENT APPLICATION

©) Date of filing: 20.12.16. © Applicant (s): AIRBUS SAFRAN LAUNCHERS SAS (30) Priority: Simplified joint stock company - FR. ©) Inventor (s): LEGLIZE LUDOVIC and GOUGEON EMMANUEL. (43) Date of public availability of the request: 22.06.18 Bulletin 18/25. (56) List of documents cited in the report preliminary research: Refer to end of present booklet @) References to other national documents ©) Holder (s): AIRBUS SAFRAN LAUNCHERS SAS related: Joint stock company. ©) Extension request (s): @) Agent (s): CABINET BEAU DE LOMENIE.

Pty DIHYDROGEN GAS GENERATION SYSTEM.

FR 3 060 552 - A1

The present invention relates to a system (1) for generating hydrogen gas, comprising at least:

- a load (3) of a hydrogen storage material,

- a heating element (5) configured to heat the load at a heating zone (Z1),

- a temperature sensor (7) in contact with the load and located at a non-zero distance (di) from the heating zone, and

- a control module (M) configured to control the intensity of the heating carried out by the heating member as a function of the temperature measured by the temperature sensor.

Invention background

The invention relates to a system for generating gaseous dihydrogen. Such a system is in particular intended to supply a fuel cell in order to allow the production of electrical energy.

Various devices for generating dihydrogen making it possible to supply a fuel cell are known from the state of the art.

These devices typically incorporate a heater and a hydrogen storage material. The heat produced by the heater transforms the hydrogen storage material and releases the gaseous dihydrogen.

Such devices generally have satisfactory operation, but certain problems can sometimes arise.

A first defect of the known devices is that the loading of the hydrogen storage material is not always consumed in its entirety. This partial consumption of the load can sometimes be reduced to the consumption of a very small amount of the load. Such situations can lead to the generation of an insufficient quantity of gaseous dihydrogen for the intended application, thus affecting the reliability of the devices concerned.

A second defect of the known devices concerns the yield of generation of dihydrogen. It has in fact been observed that, even when the entire load was consumed, the yield of generation of dihydrogen could sometimes be lower than the yield initially planned, parasitic species being generated and present in the gaseous phase produced.

There is therefore a need to provide a system for generating gaseous dihydrogen making it possible to obtain, in a reliable manner, the complete consumption of the charge and the desired yield of generation of hydrogen.

Subject and summary of the invention

To this end, the invention proposes, according to a first aspect, a system for generating gaseous dihydrogen, comprising at least:

- a loading of a hydrogen storage material,

- a heating device configured to heat the load at a heating zone,

- a temperature sensor in contact with the load and located at a non-zero distance from the heating zone, and

- a control module configured to control the intensity of the heating carried out by the heating member as a function of the temperature measured by the temperature sensor.

It is sought to impose upon loading upon its initiation by the heating member a temperature comprised within a predetermined temperature range. Indeed, a sufficiently high temperature must be imposed in order to obtain a self-sustaining transformation of the load following the initiation phase and, consequently, a complete consumption of the latter. In addition, the temperature should also not be too high in order to limit, or even eliminate, the existence of parasitic reactions and thus have an improved yield of dihydrogen formation. The temperature of the heating element at the level of the heating zone does not however correspond exactly to the temperature actually "seen" by the load. The value of this temperature differential is in practice quite difficult to predict because it results from the evolution of the thermal contact between the heating member and the load during heating, this evolution being notably linked to the change of state of the load. . Positioning the temperature sensor in contact with the load, at a non-zero distance from the heating zone, makes it possible to measure the temperature actually imposed on the load during the initiation phase and thus to check whether it is located or not within the desired working temperature range. The temperature measured by the sensor is transmitted to the control module which controls, as a function of this measurement, the heating element in order to regulate the temperature actually "seen" by the load and to ensure that it is within the range of predetermined temperature. The invention thus makes it possible to have a system making it possible to regulate the temperature effectively imposed on the load during the initiation phase, which makes it possible to obtain, in a reliable manner, the full consumption of the load and the desired yield of dihydrogen gas. .

In an exemplary embodiment, the temperature sensor is present inside the load. Alternatively, the temperature sensor is in contact with an external lateral surface of the load. This latter variant is specially adapted to the case where the load has a relatively small diameter.

In an exemplary embodiment, the heating member is present inside the load. In particular, the load defines an internal through channel in which the heating member is present.

In an exemplary embodiment, the temperature sensor is present inside the load and is located at a middle position between the heating member and an external side wall of the load.

According to a variant, the heating member is located outside the load.

The present invention also relates to an assembly intended to produce electrical energy comprising at least:

- a system as described above, and

- a fuel cell comprising an anode connected to said system and a cathode connected to a source of gaseous oxygen.

The present invention also relates to an aircraft comprising an assembly as described above.

The present invention also relates to a process for the generation of gaseous dihydrogen implementing a system as described above, comprising at least one step of initiating the loading during which the heating member heats the loading at the level of the heating zone. in order to generate the gaseous dihydrogen.

The present invention also relates to a method of producing electrical energy using an assembly as described above comprising at least one step during which the anode of the fuel cell is supplied by the gaseous dihydrogen generated according to the method described more high and during which the cathode of the fuel cell is supplied with gaseous oxygen.

Brief description of the drawings

Other characteristics and advantages of the invention will emerge from the following description of particular embodiments of the invention, given by way of nonlimiting examples, with reference to the appended drawings, in which:

FIG. 1 schematically represents an example of a system according to the invention,

FIGS. 2 to 5 schematically represent variants of systems according to the invention, and

- Figure 6 shows, schematically, an example of an assembly according to the invention for the production of electrical energy.

Detailed description of embodiments

FIG. 1 shows an example of a system 1 for generating gaseous dihydrogen according to the invention. The system 1 comprises a cartridge comprising a body formed by a side wall 11, a first bottom 13 and a second bottom 15. The body contains a load 3 of a hydrogen storage material. The load 3 can be in solid form. The hydrogen storage material can for example be borazane ("ammonia borane"). The charge 3 can comprise, in addition to the hydrogen storage material, a polymeric binder. Materials which can be used to constitute the charge 3 intended for producing the gaseous dihydrogen are known per se and need not be described in more detail here.

The load 3 extends along a longitudinal axis X which corresponds in the example illustrated to the longitudinal axis of the body. The load 3 can be of cylindrical shape and can, more generally, have a symmetrical shape of revolution around the axis X. Other shapes are however possible for the load like a parallelepiped shape, for example. In the example illustrated, the load 3 is in one piece (i.e. consisting of a single block of material). In a variant not illustrated, the charge could be in the form of a plurality of blocks each comprising the hydrogen storage material and positioned along the longitudinal axis of the body. In the latter case, the blocks are for example in the form of pellets positioned one after the other along the longitudinal axis of the body. In another variant and as will be described below, the loading can be in granular form. The load 3 has a diameter D which corresponds to its largest transverse dimension measured perpendicular to the longitudinal axis X.

In the example of FIG. 1, the load 3 defines an internal through channel 17 which extends over the entire length of the load 3. The load 3 thus has a tubular shape. The load 3 has an internal lateral surface SLi delimiting the internal channel 17. The channel 17 extends between a first end 19 located on the side of the first bottom 13 and a second end 21 located on the side of the second bottom 15. The second end 21 opens to the outside of the body through an opening 15a formed in the second bottom 15. The gaseous dihydrogen is intended to be released outside the body through the opening 15a of the second bottom 15. Loading 3 also has an external lateral surface SL ₂ facing the side wall 11 of the body, and possibly in contact with the latter.

The system 1 illustrated in Figure 1 further comprises a heater 5 which is configured to heat the load 3 in order to release the gaseous dihydrogen. In the example considered, the heating member 5 is in the form of a resistive heating element. The heater 5 is housed inside the load 3. The heater 5 is housed in the through channel 17 in the example illustrated. The heating element 5 can extend over only part of the length of the channel 17, for example over at most half the length of the channel 17. The heating element 5 is present on the side of the first bottom 13 and therefore on the side of the first end 19 of the channel 17. The heating member 5 is, as illustrated, present in a central zone in the direction of the width of the load 3. This central zone corresponds to the zone of the load 3 delimited by the planes Pa and Pb of respective equation y _a = 0.25D and yb = 0.75D, where D denotes the diameter of the load and where y _a and y _b are measured along the width of the load taking as origin a same point of the external lateral surface SL ₂ of the load 3. The first bottom 13 has a first aperture 13a which is crossed by the heating member 5. The heating member 5 may or may not be in contact with the load 3. In the example illustrated, the heating member 5 is in contact with the surface l internal inhalation SLi of the load 3. The heating element 5 is configured to heat the load 3 at a heating zone Zi present in the internal channel 17. Thus, in this example, the heating zone Zi is located at inside the load 3.

The heating carried out by the heating member 5 makes it possible to initiate charging 3 and to release the gaseous dihydrogen by transformation or decomposition of the hydrogen storage material. The gaseous dihydrogen thus released flows through the channel 17 in the direction of the second end 21. The flow of the gaseous dihydrogen is symbolized by the arrow F in the figures. The presence of the through channel 17 is advantageous because it makes it possible to use the heat of the gaseous dihydrogen to initiate the loading 3 in zones relatively distant from the heating member 5 and thus improve the energy efficiency of generation of the gaseous dihydrogen.

The system 1 also comprises a temperature sensor 7, such as a thermocouple, which is in the example illustrated located inside the load 3 and in contact with the latter. The temperature sensor 7 can, as illustrated, be "drowned" in the load 3. In the example illustrated, the temperature sensor 7 passes through a second opening 13b formed in the first bottom 13, distinct from the first opening 13a. As mentioned above, the presence of the temperature sensor 7 in contact with the load 3 at a non-zero distance di from the heating zone Zi makes it possible to measure the temperature effectively imposed on the load 3. The temperature sensor 7 may be present between the 'heater 5 and the external side wall SL ₂ . The temperature sensor 7 is in particular not present in the through channel 17.

In the configuration illustrated in FIG. 1, the heating member 5 and the temperature sensor 7 pass through the same face F1 of the load 3. More precisely, the heating member 5 extends in the load 3 over a first distance d ₂ measured with respect to the face F1 and the temperature sensor 7 extends in the load 3 over a second distance d3 measured with respect to the face F1 which is less than the first distance d ₂ . The first and second distances d ₂ and d3 are measured along the longitudinal axis X. One could, in a variant not shown, place the temperature sensor through the side wall 11 of the body with the heating element present through the first base 13. During the manufacture of the system 1, the heating member 5 and the temperature sensor 7 can be introduced into holes made in the load 3 or, alternatively, the load 3 can be molded around of these elements.

The system 1 further comprises a control module M which is connected to the temperature sensor 7 and to the heating element 5. The control module M comprises an input E connected to the temperature sensor 7 and an output S connected to the heating element 5. The control module M is configured to vary the intensity of the heating carried out by the heating element 5 at the level of the heating zone Zi, as a function of the temperature measured by the temperature sensor 7 As explained above, the presence of the control module M ensures that the temperature actually imposed on the load 3 during the initiation phase is within a predetermined temperature range. Typically, when the hydrogen storage material is borazane, it is desirable that the temperature imposed on loading 3 during initiation is between 200 ° C and 300 ° C. For this same material, the duration of the initiation phase can typically be between 30 seconds and one minute.

The control module M can act on the heating element 5 in order to reduce the intensity of the heating in response to the measurement carried out by the sensor 7. In this case, the control module M can control the heating element 5 so that the latter continues to heat the load 3 at a lower heating intensity. This continues to provide heat to the load to achieve a self-sustaining transformation while ensuring that the temperature of the load is kept within the predetermined range. Alternatively, the control module M can control the heating member 5 so that the heating of the load 3 is stopped. The latter case is of interest when it is considered that the heating member has already provided the load 3 with an amount of heat sufficient to allow the desired initiation.

The control module M can alternatively act on the heating member 5 in order to increase the intensity of the heating in response to the measurement carried out by the sensor 7. This makes it possible to guarantee that sufficient heat is supplied to the load to reach a self-sustaining transformation.

The control module M can for example comprise a computer equipped with software, such as LabView, programmed to control the heating produced by the heating member 5 as a function of the temperature measurement carried out by the temperature sensor 7.

In the configuration of FIG. 1, the temperature sensor 7 can be present at a middle position between the heating member 5 and the external lateral surface SL ₂ of the load 3. It is understood by "middle position" that the distance di is between 0.25d ₄ and 0.75d ₄ where d ₄ denotes the distance from the heater 5 to the external lateral surface SL ₂ of the load 3. The distances di and d ₄ are measured perpendicular to the longitudinal axis X of the loading 3 in the example of FIG. 1. Such a positioning of the temperature sensor 7 makes it possible to further improve the precision of the temperature regulation carried out particularly in the case of a loading of limited, smaller or equal diameter at 30 mm. When the diameter of the load is greater than 30 mm, or even greater than or equal to 45 mm, it may be advantageous to position the temperature sensor close to the heating member, that is to say at a distance di less than or equal to 0.30d ₄ .

The distance di can, as illustrated, be between D / 8 and 3D / 8 where D denotes the diameter of the load 3.

The example of system 10 illustrated in FIG. 2 is similar to that illustrated in FIG. 1 and differs from the latter in that it comprises several temperature sensors 7a and 7b present inside the load 3. Each sensor 7a and 7b is located at a non-zero distance from the heating zone Zi and is connected to the control module M. In this case, the control module M comprises a first input Ea connected to the first sensor 7a and a second input Eb connected to the second sensor 7b. The control module M further comprises an output S connected to the heating member 5. The sensors 7a and 7b are in the example illustrated each located at a different distance from the heating zone Zi but it is not beyond the scope of the invention if the sensors are equidistant from the heating zone Zi. The sensors 7a and 7b pass through a separate opening 13b or 13c formed in the first bottom 13.

FIG. 3 illustrates a system 110 where the heating member 50 is located outside of the load 31. In the configuration illustrated in FIG. 3, the heating member 50 is not in contact with the load 31. L the heating member 50 is, in the example illustrated, a laser making it possible, by focusing its beam on the heating zone Z _2, to initiate the charge 31. The charge 31 can for example be in granular form in this configuration . The granular charge 31 can for example comprise borazane granules. As a variant, the granular charge 31 may comprise beads encapsulating hydrogen, the wall of these beads being able to become permeable to hydrogen under the effect of heat. Such a wall of balls may for example be made of silica or polyurethane. In the configuration illustrated in FIG. 3, the first bottom 13 is transparent to the radiation coming from the laser 50 in order to allow initiation. In the configuration of FIG. 3, the heating zone Z ₂ is located on an external surface of the latter. The sensor 7 is present in the load 3 at a non-zero distance di from the heating zone Z ₂ . The sensor passes through a hole 11a formed in the side wall 11 of the body. In the example of FIG. 3, the distance di is measured along the longitudinal axis X of the load 3.

FIG. 4 illustrates a variant of the system 120 where the heating member 51 is present outside the load 31. The system 120 comprises a body comprising a side wall 111 delimiting an interior volume in which the load 31 and the member 51 are present. The body further comprises a first bottom 131 and a second bottom 151. In this example, the heating member 51 is located around the load 31. The heating member 51 is in the form of a resistive heating tube. The load 31 is in granular form in the example illustrated. The heating member 51 is configured to heat the load 31 at a heating zone Z ₃ located on the external lateral surface SL ₂ of the load 31. The temperature sensor 7 is present inside the load 31 at contact of the latter and is located at a non-zero distance d _x from the heating member 51. The temperature sensor 7 crosses the bottom 131 at the opening 131a.

FIG. 5 illustrates a variant of the system 130 in which the temperature sensor 70 is present outside the load 30 on an external lateral surface SL ₂ of the latter. In this example, the resistive heating element 55 is present in the internal channel passing through 170 of the load 30. The load 30 is in this configuration of relatively small diameter, which makes it possible to make a measurement representative of the temperature actually seen by the loading by placing the sensor 31 outside of the loading 30. The temperature sensor 70 is positioned through an opening 11a formed in the side wall 11 of the body.

FIG. 6 illustrates an example assembly 60 intended for producing electrical energy comprising a system 1 for generating hydrogen gas and a fuel cell 61. The fuel cell 61 comprises an anode 62 connected to said system 1 by the channel 63, a cathode 64 connected to a source of gaseous oxygen 68 through the channel 65 and possibly a cooling system 66. The presence of the cooling system 66 is optional. The source of gaseous oxygen 68 may for example be a device for storing oxygen under pressure, for example in the form of a bottle of oxygen under pressure. Alternatively, the oxygen supplied to the fuel cell can be taken from the surrounding air. The fuel cell 61 is configured to supply a device 80 with electrical energy. This assembly 60 can be present in an aircraft.

The assembly 60 of FIG. 6 comprises a single cartridge 1 for generating dihydrogen. Of course, in a variant not illustrated, the assembly may include a plurality of dihydrogen generation cartridges which can be activated independently of each other in order to generate the quantity of dihydrogen desired for the envisaged application.

The expression "included between ... and ..." must be understood as including the limits.

Claims (11)

1. System (1; 10; 110; 120; 130) for generating gaseous dihydrogen, comprising at least: - a charge (3; 30; 31) of a hydrogen storage material, - a heating device (5; 50; 51; 55) configured to heat the load at a heating zone (Zi; Z ₂ ; Z ₃ ), - a temperature sensor (7; 7a; 7b; 70) in contact with the load and located at a non-zero distance (di) from the heating zone, and - a control module (M) configured to control the intensity of the heating carried out by the heating member as a function of the temperature measured by the temperature sensor. 2. System (1; 10; 110; 120) according to claim 1, in which the temperature sensor (7; 7a; 7b) is present inside the load (3; 31). 3. System (130) according to claim 1, in which the temperature sensor (70) is in contact with an external lateral surface (SL ₂ ) of the load (30). 4. System (1; 10; 130) according to any one of claims 1 to 3, in which the heating member (5; 55) is present inside the load (3; 30). 5. System (1; 10; 130) according to claim 4, in which the load (3; 30) defines an internal through channel (17; 170) in which the heating member (5; 55) is present. 6. System (1) according to claim 4 or 5, wherein the temperature sensor (7) is present inside the load (3) and is located in a middle position between the heating member (5) and an external side wall (SL ₂ ) of the load. 7. System (110; 120) according to any one of claims 1 to 3, in which the heating member (50; 51) is located outside the load (31). 8. An assembly (60) intended for producing electrical energy comprising at least: - a system (1) according to any one of claims 1 to 7, and - a fuel cell (61) comprising an anode (62) connected to said system and a cathode (64) connected to a source of gaseous oxygen (68). 9. Aircraft comprising an assembly (60) according to claim 8. 10. A process for generating gaseous dihydrogen using the system (1; 10; 110; 120; 130) according to any one of claims 1 to 7, comprising at least one step of initiating the loading (3; 30; 31) during which the heating element (5; 50; 51; 55) heats the load at the level of the heating zone (Zi; Z ₂ ; Z ₃ ) in order to generate the gaseous dihydrogen. 11. A method of producing electrical energy using an assembly (60) according to claim 8 comprising at least one step during which the anode of the fuel cell (61) is supplied by the gaseous dihydrogen generated according to the method of claim 10 and during which the cathode (64) of the fuel cell is supplied with gaseous oxygen. 1/2 CM