FR3052231A1 - DEVICE AND METHOD FOR FILLING A PRESSURE GAS TANK - Google Patents

Abstract

A device for filling a tank (2) with pressurized gas comprising a source (3, 4) of gas under pressure, a transfer line (5) for connecting the source (3, 4) of gas to the tank ( 2) at a gas inlet orifice (6), characterized in that it comprises a recirculation pipe (7) comprising a first end intended to be connected to the tank (2) at an orifice (8) outlet of the reservoir (2) and a second end to be connected to the reservoir (2) at an inlet port (6), the recirculation pipe (7) being configured to take a fraction of the gas introduced into the tank (2) and reintroduced into the tank (2) and in that the pipe (7) for recirculation comprises a device (9) for cooling the gas circulating therein.

Description

The invention relates to a device and a method for filling a tank with gas under pressure. The invention relates more particularly to a device for filling a tank with pressurized gas comprising a pressurized gas source, a transfer line intended to connect the gas source to the tank at a water inlet port. gas.

When filling a pressurized gas tank, the gas contained in this tank is compressed. This results in a heating of this gas. This increase in temperature can be even more significant in the case of hydrogen. This heating may cause problems, especially when the tank must not be exposed to too high a temperature (for example about 70 ° C in the case of some composite tanks).

A known solution is to cool the gas under pressure upstream of its injection into the tank. This practice is common for filling hydrogen or natural gas tanks. This solution, however, consumes a relatively large amount of energy.

Another solution is to cool the tank itself. This solution is however complex and expensive.

Another solution is to fill the tank at a very low speed to allow the dissipation of the heat produced. This solution, however, considerably lengthens the filling times.

Another solution is to use phase change materials in the tank structure in order to limit the temperature of the gas around that of the phase change of the material used. The heat absorbed by these materials can then be removed via the bottle wall in a longer period of time after filling. This solution increases the cost of manufacturing the tanks.

An object of the present invention is to overcome all or part of the disadvantages of the prior art noted above. To this end, the device according to the invention, which moreover conforms to the generic definition given in the preamble above, is essentially characterized in that it comprises a recirculation line comprising a first end intended to be connected to the reservoir at a reservoir outlet port and a second end for connection to the reservoir at an inlet port, the recirculation line being configured to withdraw a fraction of the gas introduced into the reservoir and reintroduce it in the tank and in that the recirculation pipe comprises a device for cooling the gas circulating therein.

Furthermore, embodiments of the invention may comprise one or more of the following features: the transfer pipe end intended to be connected to the inlet orifice is merged or adjacent with the second end of the recirculation line, i.e. the inlet port connected to the second end of the recirculation line comprises or consists of the inlet port connected to the transfer line; end of the recirculation line is distinct from the second end of the recirculation line, that is to say that the outlet of the tank connected to the first end of the recirculation pipe is distinct from the orifice of the recirculation pipe; inlet connected to the second end of the recirculation pipe, - the first end of the recirculation pipe is merged or integrated with the second end of the pipe recirculation, that is to say that the outlet of the tank connected to the first end of the recirculation pipe is common or integrated into the gas inlet port connected to the transfer pipe; first end of the recirculation line and the end of the transfer line connected to the reservoir are concentric or adjacent, that is to say that the outlet orifices of the reservoir connected to the first end of the recirculation pipe and the gas inlet port connected to the transfer pipe are arranged concentrically or adjacent to a common opening of the tank to be filled, - the recirculation pipe comprises a sampling portion comprising a first end provided with a opening intended to be located in the internal volume of the tank and a second end connected to the gas inlet port of the transfer line, c that is, the gas is withdrawn into the reservoir via the first end of the sampling line remotely relative to the gas inlet port of the transfer line, the first end of the portion of the sampling is shifted in a longitudinal direction relative to the end of the transfer pipe intended to be connected to the gas inlet port, the gas cooling device comprises a cold source in direct or indirect heat exchange with the gas circulating in the recirculation pipe, the cooling device comprises at least one heat exchanger, the heat exchanger is in heat exchange with a cooling fluid, the device comprises a gas circulation member. in the recirculation line of the mechanical and / or electrical and / or pneumatic and / or hydraulic type, - the step of taking a fraction of the g az located in the reservoir is carried out during a process of filling the reservoir with pressurized gas transferred from the source via the transfer line, the flow of gas taken during the sampling step being less than the flow rate of gas introduced into the reservoir. tank during the filling process. the circulating member comprises at least one of a blade or propeller mechanism such as a compressor, a venturi type mechanism, the pressurized gas source comprises at least one of: or a plurality of pressurized gas storages, a compressor, a source of liquefied gas associated with a vaporizer, a chemical storage of gas, - the device comprises a set of valve (s) controlled (s) and is configured to perform a sampling of a fraction of the gas in the tank, cool the gas taken and reintroduced into the tank before and / or during a process of filling the tank with pressurized gas transferred from the source through the transfer line. The invention also relates to a method of filling a tank with pressurized gas via a filling device comprising a source of pressurized gas, a transfer line connecting the gas source to the tank at a port d gas inlet, the method comprising a step of withdrawing a fraction of the gas located in the tank, a step of cooling the withdrawn gas and a step of reintroducing the withdrawn and cooled gas into the tank.

According to other possible features: - the steps of sampling a fraction of the gas in the tank, cooling the gas taken and reintroduction of the gas taken and cooled in the tank are performed before and / or during a filling process The invention may also relate to any alternative device or method comprising any combination of the above or below features. Other features and advantages will appear on reading the description below, with reference to the figures in which: - Figure 1 shows a schematic and partial view illustrating a first example of structure and operation of a filling device according to the invention, - Figure 2 shows a schematic and partial view illustrating a second example of structure and operation of a filling device according to the invention, - Figure 3 shows a schematic and partial view illustrating a third example of structure and operation of a filling device according to the invention, - Figure 4 shows a schematic and partial view illustrating a fourth example of structure and operation of a filling device according to the invention.

Figure 1 illustrates a device for filling a tank 2 with pressurized gas. The device comprises a source 3, 4 of gas under pressure and a transfer line 5 connecting the source 3, 4 of gas to the tank 2 at a gas inlet port 6.

The reservoir 2 is preferably a composite or metallic reservoir comprising a sealed envelope defining an empty rigid storage volume, that is to say containing only gas under pressure in its internal volume.

According to an advantageous feature, the device also comprises a recirculation pipe 7 comprising a first end connected to the tank 2 at an outlet orifice 8 of the tank 2 and a second end connected to the tank 2 at an orifice 6 of Entrance. The recirculation pipe 7 is configured to take a fraction of the gas located in the tank 2 and reintroduce it into the tank 2. When it leaves the tank, the gas taken by the recirculation pipe 7 is advantageously cooled. That is, the gas in the tank 2 can be cooled by the device before and / or during filling of the tank 2 with pressurized gas transferred from the source 3, 4 via the transfer line 5. This limits heating of the tank 2 during a filling.

As illustrated in FIG. 1, the gas inlet port 6 connected to the second end of the recirculation pipe 7 may also be the gas inlet port 6 connected to the transfer pipe 5. that is to say that the recirculation pipe 7 is connected to the transfer pipe 5 and these two pipes 5, 7 are a common portion connected to the tank 2 for introducing gas into the tank 2 via the same orifice. Thus, the gas taken by the recirculation pipe 7 is mixed with the gas which passes through the transfer pipe 5.

As illustrated in Figure 1, the outlet orifice 8 of the tank 2 connected to the first end of the recirculation pipe 7 may be distinct from the inlet port 6.

The two orifices 6, 8 may be located at distinct ends of the tank 2, for example at the respective bases mounted on the tank 2 (for example offset in the longitudinal direction of the tank 2). For example, faucets, valves, manual or controlled valves can be provided at these bases.

For example two valves 13, 14 (or valves) may be provided respectively at the two ends of the recirculation pipe 7.

As schematized, preferably the device may comprise a member 12 for circulating the gas in the recirculation pipe 7, that is to say an organ that will make possible, promote or cause a flow of gas in the recirculation pipe 7 (eg via a pressure difference). This circulation member 12 may be of the active or passive type, for example of the mechanical and / or electrical and / or pneumatic and / or hydraulic type.

In the example of FIG. 1, this circulation member 12 comprises a compressor located in the recirculation pipe 7 (upstream of its junction with the transfer pipe 5).

Preferably, this compressor 12 is configured to withstand the pressure of the gas at a pressure that can reach, for example, the desired end of filling pressure in the tank 2.

The role of the member 12 is to provide the recirculation flow rate necessary to allow the heat contained in the gas inside the tank 2 to be expelled to the outside through the heat exchanger 9. The organ 12 of circulation can also raise the gas pressure at the outlet of the tank 2 so as to overcome only the pressure drop in the circuit containing the exchanger 9. Preferably, this device 12 circulation does not replace the compressor main 4 (or the corresponding pressure source).

The source 3, 4 of gas under pressure may comprise at least one of: one or more pressurized gas storage, a compressor, a source of liquefied gas associated with a vaporizer, a chemical storage of gas or any other suitable system .

The gas can be stored in the source 3 at a pressure lower than the pressure that will prevail in the tank 2 at the end of filling. It can also be stored at a pressure higher than the pressure at the end of filling.

In the example of Figure 1 the pressurized gas source comprises two members 4, 5 in series (for example a gas storage and a compressor or a liquid storage and a vaporizer). Of course this source of pressurized gas may comprise a plurality of members connected in parallel and / or in series with the transfer line 5 (in particular gas storage in parallel to perform a cascade filling, compressor (s). .). A valve or flow regulator (preferably controlled) may be placed downstream of the source 4, 5 of pressure on the transfer line 5.

For example, the device 1 may comprise a flow regulator 15 placed downstream of the source 4, 5 to control the passage of the gas from the source 4, 5 to the tank 2 (progressive valve or all or nothing). This member 15 is for example configured to regulate the flow of gas entering the tank 2 from the measurement or estimation of the pressure in the tank 2 and / or from the measurement or estimation of the flow in the tank. transfer pipe 5 and / or from the measurement or estimation of the pressure and flow in this pipe 5.

As illustrated in Figure 1, the recirculation pipe 7 preferably comprises a device 9 for cooling the gas circulating therein. This cooling device may be a simple heat exchanger in heat exchange with the air or a cooling fluid circuit. For example, the mere fact of circulating the gas in the recirculation line outside the tank 2 can allow its cooling. This cooling can be increased by putting in heat exchange a portion of this recirculation pipe 7 with a source of cold, for example a cold bath, a colder gas flow, a cold accumulator ...

The various connected ends of the fluid circuit of the device can be equipped with conventional connection systems, for example fast connection for example with self-sealing valves to prevent leakage in case of disconnection.

The embodiment of FIG. 2 differs from that of FIG. 1 in that the cooling device 9 (in this case a heat exchanger 9) is located on the transfer pipe 5, on the portion shared with the pipe 7 of FIG. recirculation. That is, the cooling device cools the recirculated gas in the line 7 and also the gas supplied from the source via the transfer line 5 as appropriate.

As before, the heat exchanger 9 is configured to contain the gas at the required filling pressure. This exchanger can exchange heat either with the outside air by convection or exchange by convection with a liquid or a gas which acts as a cold source.

According to a possible example of operation, the filling device 1 can be connected (removably) to the orifices of the tank 2 via the valves or valves or connectors 13 and 14. Progressive opening of the valves or valves 13, 14 corresponding can be achieved to balance the pressures between the inside of the tank 2 and the filling circuit 5, 7. The circulation member 12 can then be activated to establish a loop flow rate of the gas from the tank 2 to the exchanger 9 and again to the tank 2. This circulation loop will promote heat exchange between the gas contained in the tank 2 and the outside and / or a cold source. The higher the flow of (re) circulation, the greater the heat exchange will be.

Then or concomitantly, the source 4, 5 of gas under pressure and its transfer in the transfer line 5 can be activated. For example, a compressor 4 may be activated or a transfer valve may be opened.

The flow regulator 15 can be controlled to control the flow of gas from the source 4 to the tank 2.

The transfer of gas into the tank 2 carries out a gradual increase in pressure in the tank 2 while achieving a loop flow (recirculation line 7) for cooling the gas in the tank 2.

Preferably, the inlet and outlet openings 6 and 8 are separated by a determined distance to create a circulation in the tank 2 allowing a renewal of all the gas contained in the tank 2. For example the two orifices are placed respectively near two opposite longitudinal ends of the tank 2.

The filling has the effect of heating the gas contained at a temperature greater than that of the outside. The gas that is reheated as soon as it passes through the exchanger 9 will be cooled before being reintroduced into the tank 2.

The mass of gas contained in the tank 2 will increase by the fact that, overall (over a determined period of time), the flow entering the reservoir (through the inlet orifice 6) is greater than the outflow of the reservoir ( through outlet port 8 via recirculation).

The mass of gas contained in the tank 2 will increase because the inflow from the source is non-zero and positive. The element or elements of the device (source 4, 5, flow regulator 15, circulation member 12) can be controlled electrically by a computer or an automaton to maintain the gas contained in the tank 2 below a predetermined temperature. .

The end of the filling can be defined by reaching a threshold pressure value or a threshold mass or a density or a threshold temperature in the tank 2. The flow regulator 15 can then be closed. The compressor 5 or its equivalent can also be deactivated.

After the end of the filling and the possible cooling phase carried out, the pipes 5, 7 connected to the tank 2 or its interface can be detached.

The pressure that is contained in the filling circuit 5, 7 can be maintained (valves) until connected to another tank for use in the next filling.

The embodiment of FIG. 3 differs from that of FIG. 1 in that the member 12 for circulating the gas in the recirculation line 7 comprises a venturi system fed to the nozzle of the injector by the regulator. This gas jet in the venturi device has the effect of creating a relative pressure difference which will have the effect of circulating the gas during filling in the recirculation pipe 7. The pneumatic energy provided by the pressure drop at the inlet of the venturi is converted into kinetic energy in the jet of gas within the venturi. This kinetic energy is converted back into pneumatic energy. A pressure difference is established between the venturi outlet and the side inlet from the recirculation line. This pressure difference has the effect of creating a flow of gas from the outlet of the venturi to the side inlet via a passage through the tank 2 and the exchanger 9. This solution does not require additional energy to supply the pipe 7 recirculation.

The embodiment of FIG. 4 differs from that of FIG. 1 in that the tank 2 has only one orifice or gas inlet / outlet, for example equipped with a single fluidic connection base. That is to say that the gas inlets 6 and 8 of the pipes 5, 7 take the same opening of the tank 2. The system of connections which connects to the tank 2 comprises, for example, two adjacent or concentric orifices which connect to the tank (for example on a conjugate base).

The recirculation pipe 7 comprises for example a tube immersed in the tank 2, the end of which takes the gas into the tank 2 and transfers it to the outside of the tank through the cooling member 9.

This portion 10 of tube preferably approaches the bottom wall of the tank 2. The other inlet orifice 6 is connected with the interior to the tank 2 preferably at the opening of the tank 2 (at the of the base for example). That is, the sampling tube 10 and the inlet 6 form two gas passages which pass the gas out of the tank (tubelO) or into the tank (inlet 6) via the same passage through the wall or base of the tank 2.

These two accesses to the tank 2 are preferably spaced from one another in the longitudinal direction of the tank 2. This promotes a circulation of the gas in the tank 2. The two orifices 8, 6 can be arranged in concentric circuits or adjacent. Thus, the gas is withdrawn from the tank via the tube portion 10 towards the outside of the tank in the recirculation line while the cooled gas (and possibly the gas from the source is admitted into the tank through the same access tank but via a separate zone (tubing)).

It is therefore conceivable that while being simple and inexpensive structure, the invention solves the problem of temperature rise of the gas in the tank during filling. The invention can thus be applied to tanks with one or two orifices.

Claims (13)

A device for filling a tank (2) with pressurized gas comprising a source (3, 4) of pressurized gas, a transfer line (5) for connecting the source (3, 4) of gas with tank (2) at a gas inlet orifice (6), characterized in that it comprises a recirculation pipe (7) comprising a first end intended to be connected to the tank (2) at the level of an outlet (8) of the reservoir (2) and a second end for connection to the reservoir (2) at an inlet port (6), the recirculation pipe (7) being configured to take a fraction of the gas introduced into the tank (2) and reintroducing it into the tank (2) and in that the recirculation pipe (7) comprises a device (9) for cooling the gas circulating therein. 2. Device according to claim 1, characterized in that the end of the pipe (5) for transfer to be connected to the inlet port (6) is merged or adjacent to the second end of the pipe (7). ) recirculation, that is to say that the inlet orifice (6) connected to the second end of the pipe (7) for recirculation comprises or consists of the inlet orifice (6) connected to the transfer line (5). 3. Device according to claim 1 or 2, characterized in that the first end of the pipe (7) recirculation is distinct from the second end of the pipe (7) recirculation, that is to say that the outlet port (8) of the tank (2) connected to the first end of the recirculation pipe (7) is distinct from the inlet port (6) connected to the second end of the recirculation pipe (7). Device according to Claim 1 or 2, characterized in that the gas inlets (6) and outlet (8) of the transfer (5) and connecting (7) pipes are configured to take the same opening of the tank (2). ) via a connection system intended to connect to the reservoir (2) and having two adjacent or concentric orifices which connect to the reservoir, ie the reservoir (2) then comprises only one orifice or gas inlet / outlet, for example equipped with a single fluid connection base. 5. Device according to claim 4, characterized in that the recirculation pipe (7) comprises a sampling portion (10) comprising a first end provided with an opening intended to be located in the internal volume of the reservoir (2) and a second end connected to the gas inlet opening (6) of the transfer line (5), ie the gas is taken from the tank (2) via the first end of the pipe sampling device remotely with respect to the gas inlet opening (6) of the transfer pipe (5). 6. Device according to claim 5, characterized in that the first end of the sampling portion (10) is shifted in a longitudinal direction (A) relative to the end of the pipe (5) for transfer to be connected to the gas inlet port (6). 7. Device according to any one of claims 1 to 6, characterized in that the device (9) for cooling the gas comprises a cold source in direct or indirect heat exchange with the gas flowing in the pipe (7) recirculation . 8. Device according to any one of claims 1 to 7, characterized in that the cooling device (9) comprises at least one heat exchanger (9). 9. Device according to claim 8, characterized in that the heat exchanger (9) is in heat exchange with a fluid (11) cooling. 10. Device according to any one of claims 1 to 9, characterized in that it comprises a member (12) for circulating gas in the pipe (7) recirculation mechanical and / or electrical type and / or pneumatic and / or hydraulic. 11. A method of filling a tank (2) with pressurized gas via a filling device comprising a source (3, 4) of gas under pressure, a transfer line (5) connecting to the source (3, 4) ) of gas to the reservoir (2) at a gas inlet orifice (6), characterized in that it comprises a step of sampling a fraction of the gas located in the reservoir (2), a step cooling of the withdrawn gas and a step of reintroduction of the gas taken and cooled in the tank (2). 12. Method according to claim 11, characterized in that the steps of sampling a fraction of the gas in the reservoir (2), cooling the withdrawn gas and reintroduction of the gas withdrawn and cooled in the tank (2) are performed before and / or during a filling process of the tank (2) with pressurized gas transferred from the source (3, 4) through the transfer line (5). 13. The method of claim 12, characterized in that the step of removing a fraction of the gas in the reservoir (2) is performed during a process of filling the reservoir (2) with pressurized gas transferred from the source (3, 4) through the transfer line (5) and in that the flow of gas taken during the sampling step is less than the flow rate of gas introduced into the reservoir (2) during the filling process.