Sampling and analysis plate for a pressurized gas distribution station and distribution station comprising such a plate.

Abstract

Sampling and analysis plate (10) for a station (100) for distributing a pressurized gas, such as hydrogen, the plate (10) comprising a transfer line (40) having one end intended to be connected to a gas distribution circuit of the station (100), the transfer line (40) being provided with a sampling unit (20) and an analysis unit (30) arranged in series on the transfer line (40), the sampling unit (20) comprising on the transfer line (40) at least one sampling conduit (1, 2, 3) having a first end intended to be connected to a connection point of the station (100) and a second end connected to the analysis unit (30), the analysis unit (30) comprising on the transfer line (40) an analysis conduit (4, 5) comprising an analyzer (AT) configured to analyze the degree of purity of a gas sample characterized in that the transfer line (40) comprises,between the sampling unit (20) and the analysis unit (30), a control member which, in operation, maintains a flow of the gas sample transferred to the analysis unit 30 at a constant flow rate and a constant pressure greater than atmospheric pressure. Abstract figure: Fig. 1,

Description

Title of the invention: Sampling and analysis plate for a pressurized gas distribution station and distribution station comprising such a plate.

[0001] The invention relates to a sampling and analysis plate for a pressurized gas distribution station. The invention also relates to a distribution station or a filling center comprising such a plate. The gas in question may be hydrogen.

[0002] The quality of hydrogen delivered by a hydrogen refueling station (“Hydrogen Refueling Station”, HRS) must comply with the European standard EN 17214. This standard governs the acceptability thresholds for impurities in hydrogen that can damage the proton exchange membrane (PEM) fuel cell and consequently cause a (potentially irreversible) reduction in the efficiency of electricity production. Operators of HRS and filling centers must therefore ensure their customers that the H2 quality complies with this international standard.

[0003] Some hydrogen quality analyses carried out under the European standard EN 17214 have shown non-zero water content in the hydrogen and, in some cases, above the acceptability threshold of 5 ppm.mol. Feedback from operations indicates that non-zero moisture content leads to blockage of the exchangers.

[0004] Today there is no quantitative data at the HRS level on which to rely in order to understand and explain the reasons for these excesses. Indeed, several aspects remain poorly understood, such as the potential sources of humidity on an HRS, the correlation between the humidity content and the events in the life of the station (customer refueling, maintenance operations, replacement of hydrogen reserves, etc.), the optimization of the time taken to bring hydrogen into compliance following maintenance operations, etc.

[0005] A gas sampling system is known that can be installed at the nozzle of a station. This system allows a gas sample to be taken via a sampling bottle. The latter is then sent to a certified analysis laboratory in order to carry out a complete analysis of impurities in the hydrogen according to the ISO 14687 standard.

[0006] However, this sampling and analysis solution remains quite expensive and does not allow continuous monitoring of the quality of the hydrogen delivered by the station. Indeed, between two sampling campaigns, it is not possible to ensure the purity of the hydrogen delivered by the station. In addition, due to its periodic nature with a relatively low frequency, this solution does not allow the collection of a large quantity of data useful for understanding the causes of humidity in HRS. Finally, since this solution requires sampling at the station nozzle, it does not allow the analysis of hydrogen purity in other critical points of the station.

[0007] There therefore appears to be a need to develop an analysis system which overcomes the drawbacks listed above.

[0008] To this end, according to a first aspect, the invention relates to a sampling and analysis plate for a station for distributing a pressurized gas, such as hydrogen.

[0009] The plate comprises a transfer line having one end intended to be connected to a gas distribution circuit of the station. In particular, the transfer line is provided with a sampling unit and an analysis unit arranged in series on the transfer line.

[0010] The sampling unit comprises on the transfer line at least one sampling conduit having a first end intended to be connected to a connection point of the station and a second end connected to the analysis unit.

[0011] The analysis unit comprises on the transfer line at least one analysis conduit comprising an analyzer configured to analyze the degree of purity of a gas sample.

[0012] According to this first aspect of the invention, the transfer line comprises, between the sampling unit and the analysis unit, a control member which, in operation, maintains a flow of the sample transferred to the analysis unit at a constant flow rate and a constant pressure greater than atmospheric pressure.

[0013] Thanks to this flow control and pressure regulation member provided upstream of the analyzer, the operation of the plate is no longer dependent on the operating conditions of the station or the thermodynamic state of the gas circulating in the station. In particular, the control member adapts the pressure of the sample to be analyzed to the characteristics of the analyzer.

[0014] Embodiments of the invention according to this first aspect may comprise one or more of the following features: - the control body comprises at least one regulator arranged on the transfer line; - the regulator includes a pressure indicator and a valve connected to a vent manifold; - the sampling conduit is equipped with a valve configured to isolate the plate from the gas circulating in the distribution station circuit; - the sampling conduit is equipped with an anti-particle filter intended to protect the unit of analysis; - the sampling conduit is provided with a calibrated orifice to regulate the flow rate of the sample to the analysis unit; - the analyzer includes a gas micro-chromatography system; - the micro-chromatography system is equipped with a micro thermal conductivity detector configured to measure the presence of impurities such as nitrogen or methane; - the control member comprises a first reservoir containing a standard gas intended to calibrate the analyzer; - the control body comprises a second tank containing an inerting gas; - the first tank (respectively the second tank) is arranged upstream of the regulator; - the sampling unit comprises a plurality of sampling conduits; - the first ends of the sampling conduits are connected in parallel to the analysis unit by a set of valve(s); - the second ends of the sampling conduits are intended to be connected to different connection points of the distribution station; - each sampling conduit comprises, upstream of the valve assembly(s), a non-return valve intended to prevent communication between said conduit and the other sampling conduits; - the analysis unit comprises a plurality of analysis conduits each comprising an analyzer (AT) of a different type; - the analysis conduits each comprise a first end and a second end; - the first ends of the analysis conduits are connected in parallel to the sampling unit.

[0015] According to a second aspect, the invention relates to a distribution station comprising a plate according to any one of the embodiments described above.

[0016] Other features and advantages will appear on reading the description below, made with reference to the following single figure:

[0017] [Fig-1] illustrates a schematic diagram of a plate according to the invention.

[0018] [Fig.l] illustrates a station 100 for distributing a pressurized fluid, such as hydrogen, which comprises a circuit for distributing the fluid to a tank to be filled, and a sampling and analysis plate 10 connected to the distribution circuit of the station 100.

[0019] In particular, the plate 10 comprises a transfer line 40 which has one end intended to be connected to the distribution circuit of the station 100. In addition, the transfer line 40 is provided with a sampling unit 20 and an analysis unit 30 arranged in series on a transfer line 40.

[0020] The sampling unit 20 comprises on the transfer line 40 at least one sampling conduit 1, 2, 3 which has a first end connected to a connection point (or a tapping point) of the station 100 and a second end connected to the analysis unit 30. In addition, the sampling unit 20 comprises a valve VM-01, VM-02, VM-03 configured to isolate the plate 10 from the gas circulating in the distribution circuit of the station 100, an anti-particle filter FP-01, FP-02, FP-03 intended to protect the analysis unit 30, and an orifice OC-01, OC-02, OC-03 calibrated to regulate the flow rate of the sample towards the analysis unit 30.

[0021] The calibrated orifice OC-01, OC-02, OC-03 thus makes it possible to distribute the gas under conditions compatible with the technical characteristics of the analysis unit 30.

[0022] The analysis unit 30 is configured to analyze a degree of purity of the sample. It comprises on the transfer line 40 at least one analysis conduit 4, 5 equipped with an AT analyzer. In particular, the AT analyzer may comprise a gas micro-chromatography system, equipped with a thermal micro-conductivity detector. Such a detector makes it possible to control the presence of impurities such as nitrogen or methane, or to control the presence of humidity in the gas.

[0023] According to the invention, the transfer line comprises, between the sampling unit and the analysis unit, a control member which, in operation, maintains a flow of the sample transferred to the analysis unit at a constant flow rate and a constant pressure greater than atmospheric pressure.

[0024] Thus, by providing a pressure control member upstream of the analysis unit 30, the invention makes it possible to overcome variations in atmospheric pressure which are detrimental to reliable analysis. In addition, the invention makes it possible to envisage a diversity of AT analyzer technologies on the plate 10.

[0025] Advantageously, the control member comprises at least one regulator PR-01, PR-02 arranged on the transfer line 40.

[0026] In the illustrated example, the control member comprises a first regulator PR-01 and a second regulator PR-02 which are arranged in series. Each regulator PR-01, PR-02 is equipped with a pressure indicator PI-01, PI-04 and a valve SP-02, SP-03 connected to a vent manifold CE-01, CE-02. This manifold CE-01, CE-02 is configured to evacuate the gas away from the operator and users of the station 100.

[0027] In the event of failure of one of the regulators PR-01, PR-02, the calibrated orifice OC-01, OC-02, OC-03 of the sampling conduit 1, 2, 3 makes it possible to minimize the flow rate sent to the vent collector CE-01, CE-02.

[0028] Advantageously, in order to allow the analysis unit 30 to better control the presence of humidity (when this parameter is targeted), the control member comprises a micrometric valve VM-16, VM-17 configured to regulate the flow rate of the stream to be transferred to the AT analyzer. The micrometric valve VM-16, VM-17 can be arranged on the analysis conduit 4, 5, upstream of the AT analyzer.

[0029] Advantageously, the control member comprises a reservoir 6, 7 containing a standard gas intended to calibrate the AT analyzer and / or a reservoir containing an inerting gas, such as nitrogen. The reservoir 6, 7 is connected to the transfer line 40, upstream of the second regulator PR-02.

[0030] In the example illustrated, a tank 6 containing pure hydrogen and a tank 7 containing nitrogen are connected in parallel to a secondary conduit 50 which is connected to the transfer line 40 by means of a valve VM-11.

[0031] In particular, the secondary conduit 50 comprises, for example, a three-way valve VM-12 allowing connection of the tanks 6, 7. The secondary conduit 50 also comprises a stop valve VM-05, a non-return valve CA-08 and a calibrated orifice OC-04.

[0032] Advantageously, the control member comprises at least one temperature sensor TI-01, TL02 and at least one pressure sensor PI-01. The temperature sensor TI-01, TL02 and the pressure sensor PL01 are advantageously arranged on the analysis conduit 4, 5.

[0033] Temperature monitoring via the TI-01, TL02 sensor confirms that the gas is in thermal equilibrium with the outside air. Pressure measurement via the PL01 sensor confirms that the pressure is maintained at a level slightly higher than atmospheric pressure.

[0034] To ensure the operational safety of the plate 10 and the station 100, several other safety elements can be provided in addition to the vent collectors CE-01, CE-02 arranged respectively downstream of the holders PR-01, PR-02. These additional safety elements are advantageously arranged at the level of the analysis conduit 4, 5.

[0035] For example, a vent collector CE-03, CE-04, CE-05 may be provided upstream and / or downstream of the AT analyzer. This collector may be associated with a non-return valve CA-08, CA-09, CA-10, CA-11, a stop valve VM-06, VM-09 and / or a micrometric valve VM-13, VM-15 in order to prevent the migration of water contained in the ambient air towards the AT analyzer and / or towards the sampling conduit 1, 2, 3 in the event of a stoppage / absence of flow (power cut for example).

[0036] It should be noted that a shut-off valve VM-07, VM-10 may be added upstream of the AT analyzer to isolate the portion of the transfer line 40 dedicated to the analysis and allow the decompression of the sampling conduit after the analysis. In addition, needle pressure gauges DI-01, DL02, DL03, DL04 may be present to visualize the pressure in the different parts of the plate 10.

[0037] Advantageously, the sampling unit 20 comprises a plurality of sampling conduits 1, 2, 3 connected in parallel, on the one hand to the distribution circuit of the station 100 and, on the other hand, to the analysis unit 30 by a set of valve(s) VM-04, VM-19, for example three-way valves.

[0038] The sampling conduits 1, 2, 3 are intended to be connected to different sampling points of the distribution station 100, for example a high pressure sampling point (900 to 700 bars), a medium pressure sampling point (450 to 300 bars) and a low pressure sampling point (300 to 20 bars).

[0039] In order to prevent fluid communication between the sampling conduits 1, 2, 3 via the valve assembly VM-04, VM-19, each sampling conduit 1, 2, 3 preferably comprises a non-return valve CA-16, CA-15, CA-01. Advantageously, this non-return valve CA-16, CA-15, CA-01 is arranged between the anti-particle filter FP-01, FP-02, FP-03 and the calibrated orifice OC-01, OC-02, OC-03.

[0040] Advantageously, the analysis unit 30 comprises a plurality of analysis conduits 4, 5 connected in parallel to the sampling unit 20. Each conduit 4, 5 can be equipped with an AT analyzer dedicated to a specific analysis. For example, a first AT analyzer can be dedicated to the control of impurities such as nitrogen or methane. A second AT analyzer can be dedicated to humidity control.

[0041]

Claims

Claims

1. Sampling and analysis plate (10) for a station (100) for distributing a pressurized gas, such as hydrogen, the plate (10) comprising a transfer line (40) having one end intended to be connected to a gas distribution circuit of the station (100), the transfer line (40) being provided with a sampling unit (20) and an analysis unit (30) arranged in series on the transfer line (40), the sampling unit (20) comprising on the transfer line (40) at least one sampling conduit (1, 2, 3) (1, 2, 3) having a first end intended to be connected to a connection point of the station (100) and a second end connected to the analysis unit (30), the analysis unit (30) comprising on the transfer line (40) an analysis conduit (4, 5) comprising an analyzer (AT) configured to analyze the degree of purity of a gas sample characterized in that the transfer line (40) comprises,between the sampling unit (20) and the analysis unit (30), a control member which, in operation, maintains a flow of the gas sample transferred to the analysis unit 30 at a constant flow rate and a constant pressure greater than atmospheric pressure.,

2. Plate (10) according to the preceding claim, characterized in that the control member comprises at least one regulator (PR-01, PR-02) arranged on the transfer line (40).

3. Plate (10) according to the preceding claim, characterized in that the pressure regulator (PR-01, PR-02) comprises a pressure indicator (PI-1, PI-4) and a valve (SP-02, SP-03) connected to a vent manifold (CE-01, CE-02).

4. Plate (10) according to any one of the preceding claims, characterized in that the sampling conduit (1, 2, 3) is provided with the following elements: a valve (VM-01, VM-02, VM-03) configured to isolate the plate (10) from the gas circulating in the circuit of the distribution station (100), an anti-particle filter (FP-01, FP-02, FP-03) intended to protect the analysis unit (30), and an orifice (OC-01, OC-02, OC-03) calibrated to regulate the flow rate of the sample towards the analysis unit (30).

5. Platinum (10) according to any one of the preceding claims, characterized in that the analyzer (AT) comprises a gas microchromatography system.

6. Platinum (10) according to the preceding claim, characterized in that the micro-chromatography system is equipped with a micro thermal conductivity detector configured to measure the presence of impurities such as nitrogen or methane.

7. Turntable (10) according to any one of the preceding claims, characterized in that the control member comprises a reservoir (6) containing a standard gas intended to calibrate the analyzer and / or a reservoir (7) containing an inerting gas.

8. Plate (10) according to the preceding claim, taken in its connection with any one of claims 2 to 7, characterized in that the reservoir (6, 7) is arranged upstream of the regulator (PR-02).

9. Plate (10) according to any one of claims 4 to 8, characterized in that the sampling unit (20) comprises a plurality of sampling conduits (1, 2, 3), the first ends of the sampling conduits (1, 2, 3) being connected in parallel to the analysis unit (30) by a set of valve(s) (VM-04, VM-19), the second ends of the sampling conduits (1, 2, 3) being intended to be connected to different connection points of the distribution station (100).

10. Plate (10) according to the preceding claim, characterized in that each sampling conduit (1, 2, 3) comprises upstream of the set of valve(s) (VM-04, VM-19) a non-return valve (CA-1, CA-2, CA-3) intended to prevent communication of said conduit with the other sampling conduits (1, 2, 3).

11. A plate (10) according to any one of the preceding claims, characterized in that the analysis unit (30) comprises a plurality of analysis conduits (4, 5) each comprising an analyzer (AT) of a different type, the analysis conduits (4, 5) each comprising a first end and a second end, the first ends of the analysis conduits (4, 5) being connected in parallel to the sampling unit (20).

12. Station (100) for distributing a pressurized gas comprising a sampling and analysis plate (10) according to any one of the preceding claims.

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