Air-pressure membrane gas reservoir for storing hydrogen gas at low pressure

Abstract

The present invention relates to the field of gas storage systems and concerns a pneumatic membrane gas reservoir (1) for storing hydrogen gas at low pressure, comprising: a bag-like first membrane (10) adapted to delimit a hydrogen storage chamber (C1); a second membrane (20) adapted to partially delimit a pressurized chamber (C2) at least partially overlapped by the storage chamber (C1); a second membrane (20) placed on the first membrane (10), fixed impermeably at least to the second membrane (20) and arranged together with the first membrane (10) on the outside of the gas reservoir (1). a third membrane (30) adapted to define a cavity (2) opening towards the side; hydrogen supply and discharge means associated with the storage chamber (C1); means for pressurizing the pressurized chamber (C2) with air; mechanical fastening means (4) against the base surface (S) of the first membrane (1), the second membrane (20) and the third membrane (30); a natural passive ventilation system for ventilating any hydrogen losses to the outside, comprising a duct (5) adapted to connect the cavity (2) through the pressurized chamber (C2) to the outside environment.

Description

[Technical field]

[0001] The present invention relates to the field of gas storage systems, and more particularly to pneumatic membrane gas reservoirs for storing hydrogen gas at low pressure. [Background technology]

[0002] A pneumatic membrane gas reservoir, also called a membrane gas holder or pressure gas holder, generally comprises a first membrane that defines a gas storage chamber above a gas-impermeable base surface and a second membrane adapted to create a pressurized chamber (usually air) adjacent the gas storage chamber.

[0003] This base surface may be, for example, a liquid surface or another membrane joined along an edge to the first membrane.

[0004] The second membrane, in addition to partially delimiting the pressurized air chamber, also serves to protect the innermost membrane from weather, atmospheric agents, and impacts on the outer body.

[0005] The storage chamber is connected to a supply pipe and a discharge pipe for the gas contained therein, whereas the pressurization chamber is connected to an auxiliary air fan, making it possible to maintain a certain pressure therein. Thus, the pressure exerted by the pressurization chamber on the gas storage chamber makes it possible to supply the gas at a desired pressure, depending on the use of the gas.

[0006] The two chambers are anchored to the ground along the edges of the gas reservoir and are equipped with air and gas discharge valves to control the operating pressure.

[0007] These membranes are generally made from a flexible material such as woven polyester fibres and are covered or coated with a layer of a plastic material such as PVC.

[0008] To guarantee the operation and safety of the membrane gas reservoir, the impermeability of the chamber is of paramount importance: indeed, there must be no passage of gas from the reservoir chamber to the pneumatic chamber and vice versa, as well as no loss of gas or air to the outside.

[0009] The impermeability between the chambers is actually left to the integrity of the first membrane and the sealing closure of the lower edge at the base surface of the gas reservoir.

[0010] If the first membrane, especially at the joints between the various elements forming it or at the flanged connections, develops cracks, even of very small size, or if there is an incomplete seal at the lower edge of said membrane, or if there is even a small porosity in the material, the gas can transfer from the storage chamber to the air pressurization chamber. This always happens from the gas chamber to the air chamber, because the pressure of the gas is equal to the pressure of the air, plus the pressure increase caused by the weight of the first membrane. It should be borne in mind that even a small leakage of gas into the air chamber is enough to cause an explosive mixture to form inside this chamber, posing a very serious safety risk.

[0011] The importance of sealing and impermeability of the chamber is even greater in the case of gas reservoirs adapted to store hydrogen in the gaseous state.

[0012] Hydrogen's small molecular size allows it to pass through even the smallest of membranes much more easily than other flammable gases, such as methane.

[0013] Molecular hydrogen has a very low explosive ignition point: a small spark generated by friction or the buildup of a static charge on a surface is enough to cause an explosion.

[0014] Hydrogen molecules are further characterized by a wide explosion range in air mixtures: hydrogen begins to explode at a concentration of 4% by volume in air and continues to be a potentially explosive atmosphere up to a concentration of 75.6% by volume in air.

[0015] The conventional membrane gas reservoirs described above have certain limitations and disadvantages in particular applications involving hydrogen.

[0016] The first membrane of PVC coated polyester fabric, which defines the gas storage chamber, cannot be guaranteed to be impermeable.

[0017] Hydrogen permeability means that even at low pressures (positive pressure range of a few millibars), some hydrogen will always pass through the first storage membrane, resulting in the presence of hydrogen in the air volume enclosed between the first gas storage membrane and the top pressure membrane.

[0018] This poses a clear risk of hydrogen accumulating to the point where the entire volume of the gas storage becomes an explosion hazard zone (equivalent to ATEX Zone 0).

[0019] To make matters worse, the presence of constant ventilation coming from the auxiliary fans supplying and pressurizing the gas reservoir and flowing over the primary gas storage membrane can create a risk of locally electrifying this surface with a static charge such that even a small spark can cause an explosion.

[0020] In an attempt to solve at least some of these problems, which are severe with respect to leakage, pneumatic gas reservoirs are known, which are equipped with a third membrane placed above the above-mentioned first membrane and attached impermeably to at least the above-mentioned second membrane.

[0021] This third membrane is adapted to cooperate with the second membrane to bound the pressurized chamber and to define, together with the first membrane, a cavity leading to the exterior.

[0022] The presence of a third membrane, which cooperates with the second membrane to delimit the pressurized chamber, increases the degree of isolation between the two chambers and reduces the risk of gas leaking from the storage chamber and entering the pressurized chamber. The third membrane in fact forms an additional barrier to the passage of gas from one chamber to the other. Any gas losses from the storage chamber are confined in the cavity between the first and third membranes. These leaks can flow outwards, since this discharge can only take place in practice in the free space between the lower edges of the membranes, close to the ground anchorage system, although the pressure in this space is significantly lower than both the pressure of the gas and the pressure of the air in the pressurized chamber, in direct contact with the atmosphere.

[0023] Conversely, hydrogen has a very light molecular weight and tends to accumulate at the top of the cavities and push upwards, so that the hydrogen cannot escape to the atmosphere through the free space between the lower edges of the membrane.

[0024] 1m 3 Considering that the weight of hydrogen is equal to about 10% of the volume of air, each m 3 generates a vertical buoyancy of approximately 0.9 kg.

[0025] Thus, any hydrogen present within the cavity will tend to stagnate in the upper volume of the cavity, and it is unlikely that the hydrogen will flow towards the opening along the lower edge of the membrane. Summary of the Invention [Problem to be solved by the invention]

[0026] The object of the present invention is to eliminate the above mentioned drawbacks and disadvantages.

[0027] The main objective of the present invention is to provide an air-pressurized membrane gas reservoir with a gas storage chamber and an adjacent pressurized chamber, which significantly reduces hydrogen permeation into the pressurized chamber for safety and reliability benefits. More specifically, the objective of the present invention is to ensure that any hydrogen loss due to membrane porosity or coming from a particular point in the storage chamber flows outward instead of permeating into the air pressurized chamber, thereby avoiding fire or explosion of the gas reservoir. [Means for solving the problem]

[0028] These objectives are achieved by a pneumatic membrane gas reservoir for storing hydrogen gas at low pressure, which: a pouch-shaped first membrane adapted to delimit a hydrogen storage chamber placed on the base surface; a second membrane adapted to partially bound a pressurized chamber at least partially overlapping said storage chamber; a third membrane placed on and mounted on the first membrane, impermeably attached to at least the second membrane and adapted to cooperate with the second membrane to delimit said pressurized chamber and to define, together with the first membrane, a cavity leading towards the outside of the pneumatic gas reservoir; - hydrogen supply and discharge means associated with the storage chamber; - means for pressurizing the pressure chamber with air, comprising fan means and valve means for regulating and discharging the air contained in the pressure chamber; - means for mechanically fastening the first, second and third membranes to said base surface; Equipped with It is characterized by being equipped with a natural passive ventilation system including a duct adapted to connect said cavity to the outside environment through a pressurized chamber and adapted to vent any hydrogen losses to the outside.

[0029] Advantageously, the surface of the third membrane facing the first membrane is shaped to define a channel with the first membrane to collect and direct any hydrogen leakage from said cavity towards said duct.

[0030] According to a first aspect of the invention, the surface of the third membrane facing the first membrane is provided with spacer means relative to the first membrane, creating a channel in the cavity.

[0031] Alternatively, these spacer means are selected from continuous contours, discontinuous gap material, or undulations created in the surface.

[0032] In a preferred variant of the invention, at least the second and third membranes are made of an antistatic material.

[0033] According to another aspect of the invention, the mechanical fixing means comprises: a gasket disposed on the base surface and adapted to surround the pneumatic gas reservoir; - a flange mounted on the gasket and also adapted to surround a pneumatic gas reservoir; - a plurality of bolts adapted to hold said flange in place on the gasket; Equipped with At least the edges of the second and third membranes are overlapped and clamped between the gasket and the flange.

[0034] According to a possible embodiment, the duct comprises a bellows-type flexible pipe having a first and a second end, the first end being hydraulically connected to the third membrane by a first hole and the second end being connected to the outside by a second hole provided in the second membrane.

[0035] Preferably, the bellows-type flexible pipe includes reinforcing rings arranged transversely to the folds of the bellows.

[0036] The duct further comprises elastic means in the form of a coil spring disposed between the first and second ends of the flexible pipe.

[0037] According to another aspect of the present invention: the second end of the flexible pipe is provided with a flange; The second membrane comprises a protective cap for the duct, which is located near the second hole.

[0038] More preferably, the pneumatic gas reservoir comprises: a hydrogen detection sensor located at the top of the pressurized chamber proximate the second hole in the second membrane; - several lightning rod antennas arranged around the perimeter; Equipped with.

[0039] In a particularly preferred variant, the first membrane comprises a bottom membrane and a cover membrane, impermeable and attached to one another to form a bag-shaped storage chamber.

[0040] According to a possible variant of the embodiment, the pneumatic gas reservoir comprises a fourth membrane arranged above the base surface and below the first membrane, impermeably attached to the third membrane and creating an extension of the cavity to entirely surround the storage chamber.

[0041] The pneumatic gas reservoir further comprises a belt made of nonwoven fabric, which is interposed between the first membrane and the fourth membrane and adapted to occupy an extension of the cavity.

[0042] Preferably, the fourth membrane has an edge arranged to be clamped between the gasket and the flange of the anchoring means and connects to edges of at least the second and third membranes.

[0043] The main advantage obtained with the present invention comes from the presence inside the gas reservoir in a passive natural ventilation system, whereby hydrogen resulting from possible leakage and losses resulting from the permeability of the first membrane flows freely upwards inside the duct passing through the pressurized chamber and out into the atmosphere, thereby eliminating the risk of hydrogen accumulating inside the gas reservoir volume.

[0044] The flexible bellows pipe from which the duct is generated creates a continuous channel of variable extension and shape that confines the passage of hydrogen inside the volume defined between the first and second membranes.

[0045] The presence of channels in said cavities for collecting and transporting any hydrogen losses advantageously allows the hydrogen permeating through the storage membrane to flow upwards, due in part to its very light specific weight.

[0046] Spacer means present on the surface of the third membrane facing the cavity create drainage and transport channels that have a lower resistance to flow relative to the resistance of the third membrane, which is of low permeability.

[0047] The antistatic material from which the membrane is made can limit the generation of static charge and the local buildup of static charge, which can create dangerous electrical discharges and potentially even cause explosions in the presence of hydrogen concentrations greater than 4% in the atmosphere.

[0048] A reinforcing ring installed transversely on the flexible pipe provides security and resists the forces generated by the pressure of the compressed air inside the pressure chamber.

[0049] Elastic means provided along the flexible pipe ensure that it remains in a mainly vertical position during all loading and unloading steps of the chamber delimited by the first storage membrane, thereby allowing optimal natural outflow of hydrogen.

[0050] More advantageously, the tension generated by the elastic means creates an upward vertical pull on the third membrane near the fixed point of the flexible pipe, thereby creating a cusp that facilitates the natural upward accumulation of the hydrogen flow.

[0051] These and other advantages will become clearer and more apparent from the description of the invention given below with the aid of the figures which represent some examples of embodiments, illustrated as non-limiting examples. [Brief description of the drawings]

[0052] [Figure 1] 1 is a cross-sectional view of a pneumatic membrane gas reservoir according to the present invention taken along a vertical plane. [Diagram 2] FIG. 2 is a bottom view of the components of the pneumatic gas reservoir of FIG. 1. [Figure 3a] 3A-3C are detailed cross-sectional views of FIG. 2 according to various possible variants of the embodiment. [Figure 3b] 3A-3C are detailed cross-sectional views of FIG. 2 according to various possible variants of the embodiment. [Figure 3c] 3A-3C are detailed cross-sectional views of FIG. 2 according to various possible variants of the embodiment. [Figure 4] FIG. 2 is a cross-sectional view of a pneumatic membrane gas reservoir according to the present invention taken along a vertical plane, partially filled with hydrogen and in operation. [Diagram 5] FIG. 2 is a detailed cross-sectional view of the ground anchorage of the pneumatic gas reservoir of FIG. 1. [Figure 6] 1 is a cross-sectional view of a particular variant of an embodiment of a pneumatic gas reservoir according to the invention, also in relation to a ground anchoring system; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0053] FIG. 1 illustrates a pneumatic membrane gas reservoir 1 for storing hydrogen at low pressure.

[0054] The entire pneumatic gas reservoir 1 rests on and is anchored to a base surface S, which is advantageously formed by an impermeable concrete base.

[0055] The pneumatic gas reservoir 1 of the present invention comprises a first membrane 10 and a second membrane 20. The first membrane 10 defines a hydrogen gas storage chamber C1, while the second membrane 20 partially defines an air pressurization chamber C2.

[0056] The first membrane 10 can be made in one piece and closed on itself to form a bag, or, as in the illustrated variant, comprises a bottom membrane 10a and a covering membrane 10b, which are impermeable and fixed to each other by welding along their respective edges to form a storage chamber C1.

[0057] Gas supply and exhaust means (not shown) are connected to the storage chamber C1, whilst pressurisation means are connected to the pressurised chamber C2.

[0058] The gas supply and exhaust means comprise suitable pipes and flanged connections at the first storage membrane 10, whilst the pressurisation means advantageously comprises a fan 3 (or air compressor) and a pipe 24 connected to the second membrane 20.

[0059] The pneumatic gas reservoir 1 comprises a third membrane 30, which is placed on top of the first membrane 10 and is fixed impermeably to at least the second membrane 20 and adapted to cooperate with the second membrane 20 to define the boundary of the pressurized chamber C2 and, together with the first membrane 10, to define a cavity 2 leading towards the outside of the pneumatic gas reservoir 1.

[0060] For this purpose, the pneumatic gas reservoir 1 is provided with a passive natural ventilation system, which is adapted to vent any hydrogen losses towards the outside and comprises a duct 5 adapted to pass through the pressurized chamber C2 and connect the cavity 2 to the external environment.

[0061] Referring specifically to FIG. 2 , the lower surface of the third membrane 30, i.e. the surface facing the first membrane 10, is shaped to define channels 6 therewith, which collect and transport any hydrogen losses that permeate the first membrane 10 and accumulate in the cavity 2.

[0062] The channel 6 has the role of directing the hydrogen towards the top of the cavity 2 and then towards the duct 5 .

[0063] In order to create the channels 6 in the cavity 2, the surface of the third membrane 30 facing the first membrane 10 is provided with spacer means 7 relative to the first membrane 10, i.e. projecting elements of continuous or discontinuous type, which are obtained from or added to the membrane.

[0064] The spacer means 7 is selected from continuous profiles arranged radially below the surface of the third membrane, or discontinuous gap material uniformly disposed below this surface.

[0065] Figures 3a, 3b and 3c illustrate different types of spacer means 7, which may be more or less protruding and spaced apart by larger or smaller distances.

[0066] The undulations in the surface of the third membrane 30 may even be sufficient to create the channels 6 in the cavity 2. In the case of direct contact between the two membranes 10, 30, the undulations in the underside of the third membrane 30 create empty microchannels into which hydrogen can permeate and flow upwards.

[0067] For this purpose, the first membrane 10 is made of a woven fabric coated on both sides with PVC, whereas the third membrane 30 is also made of a woven fabric, but the face in contact with the first membrane 10 is coated with a material having lubricating properties other than PVC, advantageously silicone, for example, thereby preventing the membranes from adhering to each other and leaving an accumulation space for the permeated hydrogen.

[0068] The duct 5 comprises a bellows-type flexible pipe 15 having a first end 15' and a second end 15'', the first end 15' being hydraulically connected to the third membrane 30 by a first hole 13 and the second end 15'' being connected to the outside by a second hole 14 provided in the second membrane 20.

[0069] Holes 13,14 are both provided at the top of the respective membranes 30,20.

[0070] The second end 15 ″ of the flexible pipe 15 is provided with a flange 17 for fastening to a second membrane 20 .

[0071] To prevent rain or other objects from entering from the outside, the second membrane 20 is provided with a protective cap 18 for the duct 5 at the second hole 14 .

[0072] A flexible pipe 15 creates a closed continuous channel, which connects the cavity 2 to the external environment and passes through the pressurized chamber C2 for the passage of hydrogen.

[0073] By creating the flexible pipe 15 with a deformable bellows, for example made of rubber, it is possible to compensate for any mutual movements between the membranes 30, 20.

[0074] In order to enable the flexible pipe 15 to maintain a continuous channel in a mainly vertical position so as to optimize the natural flow of hydrogen out into the atmosphere, elastic means 16 are inserted into this pipe, which in fact remains under tension against the third membrane 30.

[0075] Elastic means 16 of the coil spring type are arranged between the first end 15' and the second end 15'' of the flexible pipe 15.

[0076] Furthermore, the bellows-type flexible pipe 15 preferably includes reinforcing rings (not shown) arranged transversely to the folds of the bellows.

[0077] To improve its functionality, the pneumatic gas reservoir 1 is equipped with various safety means and devices.

[0078] In order to reduce the risk of electrostatic build-up on the second membrane 20 in the vicinity of the flange 17 for fixing the flexible pipe 15, the second membrane is made of an antistatic material. Similarly, the third membrane 30 is also made of an antistatic material.

[0079] To regulate and vent the pressurized air, the gas reservoir 1 is provided with a valve 25, which is installed on top of the second membrane 20 to allow the air present in the pressurized chamber C2 to flow out, diluting and eliminating any potential hydrogen leakage caused by a cut or damage in the third membrane 30 into the atmosphere.

[0080] Furthermore, the gas reservoir is equipped with a lightning protection antenna 22 around the periphery, which further eliminates the risk of fire due to air discharge.

[0081] Finally, the gas reservoir 1 is equipped with a hydrogen leak sensor 19 installed near the top of the outer second membrane 20. In case of serious damage, the presence of an explosive mixture of hydrogen in the air can be notified to the user, thus triggering an alarm, enabling the plant operator to immediately shut off the flow of hydrogen to the gas reservoir and empty the remaining contents by means of a specially provided ventilation valve (not shown) in the gas line.

[0082] With particular reference to figures 5 and 6, the mechanical fastening means 4 of the membranes 10, 20, 30 to the base surface S of the pneumatic gas reservoir 1 are illustrated.

[0083] For the operation of the pneumatic gas reservoir 1 it is important that all three membranes 10, 20, 30 are impermeable and fixed to one another, and the mechanical fixing means 4 are also of the gas-tight type.

[0084] The first membrane 10 covering membrane 10b stretches to produce a free end 11 once it has been welded to the corresponding bottom membrane 10a.

[0085] In the variant of FIG. 5 the mechanical fixing means 4 are: a gasket 8 arranged on the base surface S and adapted to surround the pneumatic gas reservoir 1; - a flange 9 placed on the gasket 8 and also adapted to surround the pneumatic gas reservoir 1; - a number of anchor bolts 12 or steel tie rods adapted to hold the flange 9 in place on the gasket 8; Equipped with The edges 11 , 21 , 31 of the membranes 10 , 20 , 30 are overlapped with one another and clamped between the gasket 8 and the flange 9 .

[0086] The anchor bolts 12 ensure mechanical spot fixing of the flange 9 to the base surface S, while the gasket 8 ensures uniform contact with the base surface S.

[0087] With particular reference to FIG. 6, the pneumatic gas reservoir 1 comprises a fourth membrane 40, which is disposed above the base surface S and below the bottom surface 10a of the first membrane 10.

[0088] The fourth membrane 40 is impermeable and fixed to the third membrane 30 and creates an extension of the cavity 2, whereby the cavity 2 totally surrounds the storage chamber C1.

[0089] The cavity 2 thus collects any hydrogen losses directed towards the base surface S below the gas reservoir 1 and directs them towards the natural passive ventilation system 5 .

[0090] The fourth membrane 40 has the same characteristics as the third membrane 30 and is therefore made of an antistatic fabric coated with PVC and is covered with silicone only on the side facing the bottom membrane 10a.

[0091] The gas reservoir 1 comprises a belt 23 made of TNT interposed between the bottom membrane 10a of the first membrane 10 and the fourth membrane 40, which is adapted to occupy the above-mentioned extension of the cavity 2 and to act as a spacer between the two membranes 10, 40 and as a distributor of hydrogen losses.

[0092] Because of the weight of the gas reservoir, the channels would resist in the extension of the cavity 2, making it difficult to collect and transport the hydrogen, so this is overcome by using the micro-channels present in the TNT belt 23.

[0093] To ensure the continuity of the cavity 2 around the entire periphery of the storage chamber C1, the third membrane 30 and the fourth membrane 40 must be sealed to each other in an airtight manner.

[0094] Using the mechanical fastening means 4 described above, the free edge 41 of the fourth membrane 40 is also placed below the pre-connected edges 21, 31 of the two membranes 20, 30 that are already impermeably fixed to one another, and is also positioned between the gasket 8 and the flange 9.

[0095] In this case, the bag-shaped first membrane 10 is provided with radially arranged discontinuous fastening portions (not shown) in the form of bands, which are likewise fastened with fastening means 4 between the gasket 8 and the flange 9, the sole function of which is to hold the bag in place in the storage chamber C1.

[0096] Alternatively, if the first membrane 10 has a free edge 11, the free end 11 will have an opening located near the chamber C1 and adapted to connect the lower part of the cavity to the upper part and help the hydrogen rise towards the duct 5.

[0097] 4 and 6, the operation of the pneumatic membrane gas reservoir 1 according to the present invention is illustrated.

[0098] During operation of the pneumatic gas reservoir 1, the storage chamber C1 is filled with hydrogen or emptied itself, changing its shape and volume, while the pressurized chamber C2, which follows the change in volume, is maintained at a certain pressure level by the pressurizing means described above.

[0099] The pressing force exerted by chamber C2 on the adjacent chamber C1 allows gas to be delivered at a desired pressure and facilitates emptying of storage chamber C1.

[0100] Any hydrogen escaping from the storage chamber C1 into the space between the first membrane 10 and the third membrane 30, and, if applicable, the fourth membrane 40, is collected in the cavity 2 created thereby and is released directly to the atmosphere through a passive natural ventilation system, i.e., duct 5, preventing hydrogen from penetrating into the pressurized chamber C2 and thereby posing a risk of fire or explosion.

[0101] In particular, any hydrogen loss is released to the outside through the flexible bellows pipe 15. The flexible bellows pipe 15 connects the top of the third membrane 30, where the hydrogen forced upwards actually tends to accumulate, to the external environment above the pressurized chamber C2.

Claims

1. A pneumatic membrane gas storage device (1) for storing hydrogen at low pressure, A bag-shaped first membrane (10) is fitted to define the boundary of the hydrogen storage chamber (C1) placed on the base surface (S), A second membrane (20) is fitted to partially define the boundary of a pressurized chamber (C2) which is superimposed on the hydrogen storage chamber (C1), at least in part. A third membrane (30) is installed on top of the first membrane (10), fixed impermeably to at least the second membrane (20), adapted to cooperate with the second membrane (20) to define the boundary of the pressurized chamber (C2), and together with the first membrane (10) to define a cavity (2) that extends outward from the pneumatic membrane gas storage device (1), A means for supplying and discharging hydrogen, associated with the hydrogen storage chamber (C1), The pressurizing means for pressurizing the pressurizing chamber (C2) by air includes a fan means (3) and a valve means for adjusting and discharging the air contained in the pressurizing chamber (C2), Mechanical fixing means (4) for the first film (10), the second film (20), and the third film (30) to the base surface (S), Equipped with, Here, the pneumatic membrane gas storage device (1) is, A pneumatic membrane gas storage device (1) is characterized by comprising a natural passive ventilation system adapted to ventilate any hydrogen leakage toward the outside, including a duct (5) that passes through the pressurized chamber (C2) and is adapted to connect the cavity (2) to the external environment.

2. The pneumatic membrane gas storage device (1) according to claim 1, characterized in that the surface of the third membrane (30) facing the first membrane (10) is formed to define a channel (6) together with the first membrane (10), and any hydrogen leakage is collected and sent from the cavity (2) toward the duct (5).

3. The pneumatic membrane gas storage device (1) according to claim 2, characterized in that the surface of the third membrane (30) facing the first membrane (10) is provided with a spacer means (7) relative to the first membrane (10), and the channel (6) is created in the cavity (2).

4. The pneumatic membrane gas storage device (1) according to claim 3, characterized in that the spacer means (7) is selected from a continuous outer shape, a discontinuous gap material, or undulations generated on the surface.

5. The pneumatic membrane gas storage device (1) according to claim 1, characterized in that at least the second membrane (20) and the third membrane (30) are made of an antistatic material.

6. The mechanical fixing means (4) is A gasket (8) is positioned on the base surface (S) and is adapted to surround the pneumatic membrane gas storage device (1). A flange (9) is installed on the gasket (8) and is also fitted to surround the pneumatic membrane gas storage device (1). A plurality of anchoring bolts (12) are fitted to hold the flange (9) in a predetermined position on the gasket (8). To be equipped with, At least the edges (21, 31) of the second membrane (20) and the third membrane (30) are overlapped and fastened between the gasket (8) and the flange (9), A pneumatic membrane gas storage device (1) according to claim 1, characterized by the above.

7. The pneumatic membrane gas storage device (1) according to claim 1, wherein the duct (5) comprises a bellows-type flexible pipe (15) having a first end (15') and a second end (15''), the first end (15') being fluidly connected to the third membrane (30) by a first hole (13), and the second end (15'') being connected to the outside by a second hole (14) provided in the second membrane (20).

8. The pneumatic membrane gas storage device (1) according to claim 7, characterized in that the bellows-type flexible pipe (15) is provided with a reinforcing ring arranged transversely to the flexible pipe (15) at the folds of the bellows.

9. The pneumatic membrane gas storage device (1) according to claim 7, characterized in that the duct (5) comprises a coil spring elastic means (16) disposed between the first end (15') and the second end (15'') of the flexible pipe (15).

10. The pneumatic membrane gas storage device (1) according to claim 7, characterized in that the second membrane (20) comprises a protective cap (18) for the duct (5) installed in the second hole (14).

11. The pneumatic membrane gas storage device (1) according to claim 7, characterized in that it comprises a hydrogen detection sensor (19) installed at the top of the pressurizing chamber (C2) near the second hole (14) of the second membrane (20).

12. The pneumatic membrane gas storage device (1) according to claim 1, characterized in that the first membrane (10) comprises a bottom membrane (10a) and a covering membrane (10b), which are impermeable to each other and fixed together to form the hydrogen storage chamber (C1).

13. A pneumatic membrane gas storage device (1) according to claim 1, characterized in that a fourth membrane (40) is disposed on the base surface (S) and below the first membrane (10), the fourth membrane (40) is impermeable to the third membrane (30) and generates an extension of the cavity (2) to surround the hydrogen storage chamber (C1) as a whole.

14. The pneumatic membrane gas storage device (1) according to claim 13, further comprising a belt (23) inserted between the first membrane (10) and the fourth membrane (40), made of TNT and adapted to occupy the extension of the cavity (2).

15. A fourth membrane (40) is positioned on the base surface (S) and below the first membrane (10), wherein the fourth membrane (40) is impermeable to the third membrane (30) and creates an extension of the cavity (2) to surround the hydrogen storage chamber (C1) as a whole. The pneumatic membrane gas storage device (1) according to claim 6, characterized in that the fourth membrane (40) has an edge portion (41) positioned to be fastened between the gasket (8) and the flange (9) of the mechanical fixing means (4), and is connected to at least the edge portions (21, 31) of the second membrane (20) and the third membrane (30).

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