Method for storing hydrogen gas, hydrogenation reactor and transport container

Abstract

A method for storing hydrogen gas includes the process steps pre-heating of an at least partially dehydrogenated hydrogen carrier material, storing the hydrogen gas in chemically bound form on the hydrogen carrier material as well as cooling and conditioning of the at least partially hydrogenated hydrogen carrier material.

Claims

1. A method for storing hydrogen gas, the method comprising the process steps: pre-heating an at least partially dehydrogenated hydrogen carrier material; storing hydrogen gas in chemically bound form on the at least partially dehydrogenated hydrogen carrier material and thus hydrogenating the at least partially dehydrogenated hydrogen carrier material into at least partially hydrogenated hydrogen carrier material; and cooling and conditioning the at least partially hydrogenated hydrogen carrier material, wherein pre-heating of the at least partially dehydrogenated hydrogen carrier material comprises a contacting with the at least partially hydrogenated hydrogen carrier material.

2. The method according to claim 1, wherein storing the hydrogen gas takes place at a process pressure between 30 bar and 60 bar.

3. The method according to claim 1, further comprising conditioning the hydrogen gas, wherein conditioning the hydrogen gas comprises at least one of pre-heating the hydrogen gas and separating at least one impurity.

4. The method according to claim 3, wherein separating the at least one impurity comprises at least one separation stage.

5. The method according to claim 3, wherein separating the at least one impurity shows at least one of a catalytic conversion and an adsorptive drying.

6. The method according to claim 3, wherein separating the at least one impurity comprises desulfurization.

7. The method according to claim 3, wherein conditioning the hydrogen gas takes place until an adjustable degree of purity of the hydrogen gas is achieved.

8. The method according to claim 3, wherein the at least one impurity is present in at least one a solid aggregate state and a gaseous aggregate state.

9. The method according to claim 3, wherein the separation comprises several separation stages.

10. The method according to claim 3, wherein the at least one separation stage serves for separating an impurity of a specific aggregate state.

11. The method according to claim 1, wherein cooling the at least partially hydrogenated hydrogen carrier material takes place by an additional cooling unit.

12. The method according to claim 1, wherein conditioning the at least partially hydrogenated hydrogen carrier material comprises a removal of physically dissolved hydrogen gas in the at least partially hydrogenated hydrogen carrier material.

13. The method according to claim 1, wherein storing the hydrogen gas takes place at a process temperature between 200° C. and 350° C.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1 is a schematic side view of a transport container with a hydrogenation reactor according to the invention;

(3) FIG. 2 is an enlarged schematic side view of the hydrogenation reactor in FIG. 1;

(4) FIG. 3 is a schematic side view, corresponding to FIG. 1, of a transport container with a hydrogenation reactor according to a second embodiment.

DESCRIPTION OF PREFERRED EMBODIMENTS

(5) A transport container 1 shown in FIG. 1 is known as such and can be transported without complications with a ship, a truck and/or a railroad car. The transport container 1 has standardized dimensions.

(6) In the transport container 1, a hydrogenation reactor 2 is arranged, which is connected with an LOHC storage container 3 by means of an LOHC supply line 4 and an LOHC output line 5. LOHC serves as a hydrogen carrier medium. It is also conceivable to provide two separate LOHC storage containers, whereas a first LOHC storage container is connected with the hydrogenation reactor 2 via a the LOHC supply line 4 and a second LOHC storage container is connected with the hydrogenation reactor 2 via the LOHC output line 5. By this means, the separate stocking of LOHC in an at least partially hydrogenated or partially dehydrogenated state is possible.

(7) The LOHC storage container 3 is connected by means of an LOHC source 6 via a line 7. The LOHC source 6 can be an external source, as for example an LOHC transport vehicle. The external source can also be an external LOHC supply grid, to which the transport container 1 can be connected.

(8) In addition or alternatively, the LOHC source 6 can show a dehydrogenation reactor or be connected therewith, whereas the dehydrogenation reactor serves for discharging, i.e. at least partially dehydrogenating, LOHC. For this purpose, at least partially charged LOHC is discharged in the dehydrogenation reactor, which is not shown, i.e. hydrogen is released. The released hydrogen gas may, for example, serve for the conversion into electricity in a fuel cell. The electric power can be used, i.e. consumed, on site, at least partially be used for operating the transport container 1 and the components comprised therein and/or be fed back to a, in particular, public power supply.

(9) The LOHC source 6 is, in particular, arranged outside the transport container 1. The line 7 can have a suitable interface in order to create an uncomplicated connectivity with the LOHC source. The LOHC source 6 is, in particular, arranged stationarily in a place of electricity use and/or electricity feed-in. It is possible to integrate the LOHC source 6 at least partially into the transport container 1, in particular in the form of the dehydrogenation reactor and/or the fuel cell.

(10) The LOHC supply line 4 serves for supplying at least partially dehydrogenated LOHC from the LOHC storage container 3 into the hydrogenation reactor 2. The LOHC output line 5 serves for discharging at least partially hydrogenated LOHC from the hydrogenation reactor 2 into the LOHC storage container 3.

(11) The hydrogenation reactor 2 is connected with a hydrogen source 8 via a hydrogen line 9. The hydrogen source 8, for example, is configured as an electrolyzer and allows for providing hydrogen gas, which can be stored in the hydrogenation reactor 2 in chemically bound form on the hydrogen carrier material. Other hydrogen sources are conceivable, as well. It is advantageous that the transport container 1 is connectable to different hydrogen sources.

(12) In the following, the hydrogenation reactor 2 will be described in more detail referring to FIG. 2. The hydrogenation reactor 2 has a reactor housing 10, in which a number of catalyst mounts 11 are arranged. On each catalyst mount 11, a catalyst carrier with catalyst material 12 is arranged. In the embodiment shown, the catalyst mounts 11 are lying, i.e. are arranged essentially horizontally.

(13) It is conceivable to arrange the catalyst mounts 11 in an inclined manner relative to the horizontal and in particular perpendicularly. The catalyst mounts 11 with the catalyst material 12 configure a catalyst fixed bed. The hydrogenation reactor can be operated in a one-stage manner.

(14) The catalyst mounts 11 may show tubes and/or plates and in particular be built of tubes and/or plates. The catalyst mount 11 is at least partially filled with catalyst material 12. However, the catalyst mount 11 may also be entirely filled with catalyst material 12. Glass balls, metal balls or metallic structures such as tubes, nets or grids, which are arranged on the inside and/or on an outer side of the catalyst mount 11 and attached thereto, may serve as catalyst carrier material.

(15) On the catalyst mounts 11, a cooling unit 13, respectively, is provided to allow for a direct an efficient cooling of the catalyst material 12. By this means, it is ensured that the heat produced during the hydrogenation is reliably discharged from the catalyst material 12 and/or the catalyst mount 11.

(16) The cooling unit 13, in particular, is integrated into the catalyst mount 11. The cooling unit 13, in particular, is configured as a sleeve filled with liquid, vapor and/or gas.

(17) In the reactor housing 10, a distribution unit 14 is connected with the LOHC supply line 4. The distribution unit 14 is essentially configured in the form of a shower head and allows for a distributed supply of the at least partially dehydrogenated LOHC 15 to the catalyst material 12 on the catalyst mounts 11.

(18) The distribution unit 14 may, in particular, show capillaries, flow breakers and/or distribution trays in order to ensure a reliable, homogeneous distribution of the LOHC educt to the catalyst mounts 11.

(19) The hydrogenation reactor 2 has an LOHC outlet opening 16. By means of a collection facility 18, at least partially hydrogenated LOHC 15 is discharged from the hydrogenation reactor 2 via the LOHC outlet opening 16 and the LOHC output line 5. The collection facility 18 may be a bell-mouthed collection tank with an output line. Other embodiments of the collection facility 18 are conceivable, as well.

(20) The hydrogenation reactor 2 has a hydrogen gas supply opening 17, via which hydrogen gas is supplied from the hydrogen source 8 via the hydrogen line 9 to the hydrogenation reactor 2. It is advantageous if the hydrogen gas supply opening 17 is arranged adjacent to the catalyst mounts 11 on the reactor housing 10.

(21) In particular, inside the reactor housing 10, a compensating unit, which is not shown, may be provided in order to supply the hydrogen gas specifically to the catalyst mounts 11. The compensating unit is, in particular, arranged between the catalyst mounts 11 and/or around the catalyst mounts 11 in order to allow for a reliable supply of the hydrogen gas to the filling of the catalyst material. In particular, this allows for a uniform supply of the gas. The hydrogen gas supply opening 17 is arranged along the vertical direction above the catalyst mounts 11.

(22) Due to the low density of the hydrogen gas, which causes an automatic rise of the hydrogen gas within the reactor housing 10, the hydrogen gas supply opening 17 may be arranged along a vertical direction below the catalyst mounts 11. In this case, the catalyst material 12 is contacted from above with LOHC 15 and from below with hydrogen gas. Other contacting procedure are possible, as well.

(23) In the following, the function of the hydrogenation reactor according to a first method will be described in more detail. An educt flow with at least partially dehydrogenated LOHC 15 as hydrogen carrier material is supplied from the LOHC storage container 3 via the LOHC supply line 4 to the hydrogenation reactor. Before the supply, the LOHC educt is contacted with at least partially hydrogenated hydrogen carrier material, i.e. LOHC product, from the hydrogenation reactor 2, and thus pre-heated. At the same time, the at least partially hydrogenated hydrogen carrier material is cooled and, if needed, purified.

(24) The LOHC supply line 4 and the LOHC outlet line 5 can be arranged together and/or adjacent to each other, at least section-wise, in order to allow for a direct or indirect contacting of LOHC educt and LOHC product, in particular in the counterflow process.

(25) The hydrogenation of the at least partially uncharged hydrogen carrier material takes place, according to the embodiment shown, in the hydrogenation reactor 2 at a reaction pressure of about 45 bar and a reaction temperature of about 230° C. The hydrogen gas to be stored is conditioned by means of a conditioning unit, which is not shown, before the supply from the hydrogen source 8. The conditioned hydrogen gas is contacted with the LOHC 15 in the hydrogenation reactor 2 on the catalyst material 12 and thus chemically bound to the LOHC. The LOHC product is discharged from the hydrogenation reactor 2 via the LOHC output line 5, can be used for pre-heating the uncharged LOHC, as already mentioned above, and is subsequently stocked in the LOHC storage container 3. Beforehand, a cooling and conditioning of the at least partially hydrogenated hydrogen carrier material takes place.

(26) A second embodiment of the invention is described referring to FIG. 3. Constructively identical parts obtain the same reference numbers as with the first embodiment, whose description is herewith referred to. Constructively different, but functionally similar parts obtain the same reference numbers with a postpositioned a.

(27) First of all, from an LOHC storage container 3a, partially uncharged LOHC 15 is conveyed into the transport container 1. The LOHC storage container 3a may also be arranged inside the transport container 1.

(28) In a heat recuperation unit 19, the LOHC 15 is pre-heated. Hydrogen from a hydrogen source 8 is conveyed into the transport container 1 via a hydrogen line 9. In a pre-conditioning unit 20, the pre-conditioning of the hydrogen takes place, for example by drying or filtering of solid parts and/or pre-heating.

(29) In the hydrogenation reactor 2, pre-heated LOHC 15 and conditioned hydrogen are contacted. The at least partially charged LOHC 23 from the hydrogenation reactor 2 is processed in a post-conditioning unit 21, in particular, for example, by degassing, with the result that subsequently, the simple handling of the LOHC 23 is ensured. If needed, the LOHC product is entirely or partially used before or after the post-conditioning in order to pre-heat the LOHC educt in the heat recuperation unit 19, which may take place by direct or indirect contacting. Entirely conditioned and charged LOHC 23 is transferred to a second storage container 22 arranged outside the transport container 1.

(30) The conditioning of the LOHC 23 after the hydrogenation reactor 2, in particular, is carried out such that in the second LOHC storage container 22, a dangerless stocking is possible. A creation of an explosive atmosphere through residual hydrogen is avoided.

(31) While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.