Patent Application
20250012769
The invention relates to a method and system for determining and ensuring the origin of hydrogen.
The use of environmentally friendly, low greenhouse gas (GHG) intensity hydrogen is presently considered as one of the key elements in fighting against climate change. Such hydrogen can be used as a substitute for coal, oil or gas in industry applications that cannot directly be powered by electricity.
Thus, in the near future hydrogen is forecast to be one of the main energy sources for the industry.
Hydrogen can be produced by different processes and from different feedstocks and energy sources used. Thus, hydrogen is typically differentiated by its origin, indicating the feedstock, energy source and the production process. The origin of the hydrogen is sometimes indicated by different “colors” of the hydrogen. An exemplary differentiation of the origin of hydrogen and its GHG footprint is shown in Table 1:
In the future, hydrogen of various origins will likely be available on the market at various prices. In general, the lower the GHG footprint of the hydrogen, the higher the production cost and the price will be.
Presently, green hydrogen which is produced from water by electrolysis with power from a renewable energy source, like wind, solar, hydro, geothermal or tidal energy, is considered as the most environmentally friendly form of hydrogen. Thus, it has the best GHG footprint as shown in Table 1.
On the other side of the scale black hydrogen that is produced out of black coal by gasification is considered to have a high GHG footprint.
Since the price of the hydrogen of different origins is likely to differ considerably, it is desirable for a customer to ensure that the hydrogen received is of the acquired origin and has the desired GHG footprint. Mixing various types of origins might help to reduce the cost of production, e.g. from 7$/kg to 1$/kg. Therefore, the origin of purchased hydrogen should be monitored.
Further, hydrogen might be delivered from the producer to the consumer through pipelines or classical transportation in high-pressure tanks which do not easily allow differentiation of its origin.
Therefore, it is an object of the present invention to provide a method and a system that enables to verify the origin of hydrogen, in particular to differentiate between hydrogen produced by electrolysis and hydrogen produced directly from fossil fuels.
The above-mentioned object is solved by a method for assessing and certifying the origin of hydrogen according to claim 1 and a system for assessing and certifying the origin of hydrogen according to claim 9.
Preferably, the above-mentioned object is solved by a method for assessing and certifying the origin of hydrogen, the method comprising the following steps:
Thus, the method assesses and certifies the origin of hydrogen gas. First, a quantity of hydrogen gas is sampled, preferably measured by different measuring means to obtain certain chemical or physical information about the hydrogen gas. Preferably, the sampling step can be used to determine if a certain chemical element or composition is contained in the gas. Further, from these sampling results the origin of the hydrogen gas is assessed. Preferably, a specific logic can be used to interpret the sampling results to assess the origin of the hydrogen gas with a specific certainty. Finally, the origin of the hydrogen gas is certified. For this certification for example smart certificates for example by using blockchains can be used to ensure correctness of certification.
Preferably, in a first embodiment the step of assessing the origin of the hydrogen gas from the sample comprises:
By such an assessment procedure, a simple and fast assessment of electrolytic hydrogen is possible with some certainty. However, it may be difficult to differentiate electrolysis-produced hydrogen from highly-purified hydrogen from fossil fuels based on CO determination alone. Further, it is possible to detect grey or blue hydrogen but it is difficult to distinguish grey from blue hydrogen. The presence of impurities in hydrogen fuel depends on the feedstock and production process used. Carbon monoxide can be found in hydrogen produced using steam methane reforming or gasification processes. Thus, a CO positive determination in the hydrogen gas sample indicates that the hydrogen is gray or blue. The presence of CO in the hydrogen comes from the steam reforming process. This process can also generate some CO2 (through the “Water Gas Shift” reaction) which is easier to purify through a “Pressure Swing Adsorption” (PSA) unit. Therefore, the assessment of CO in the sample could be replaced by an assessment of CO2 in the sample or an assessment of CO and CO2 in the sample.
Further, since by this assessment procedure the source of electrical energy used for electrolysis production cannot be determined, the electrolytic hydrogen can also be purple/pink hydrogen—made with nuclear power—or yellow hydrogen made with mixed-grid energy, see Table 1.
Preferably, in a second embodiment the step of assessing from the sample the origin of the hydrogen gas comprises:
The assessment procedure of the second embodiment improves the certainty in the determination of electrolytic hydrogen. In this embodiment it is possible to differentiate electrolytic hydrogen from more purified hydrogen produced from fossil feedstocks or a mix of electrolytic and fossil-derived hydrogen. Further, it is possible to identify hydrogen from fossil feedstocks but it is not possible to distinguish grey from blue hydrogen. Further, the electrolytic hydrogen can also be purple, pink or yellow hydrogen.
Preferably, in a third embodiment the step of assessing from the sample the origin of the hydrogen gas comprises:
By the assessment procedure of the third embodiment a further improved assessment of electrolytic hydrogen is possible with better certainty based on the detection of additional impurities, preferably still existing methane (CH4) in the hydrogen sample. In this embodiment it is possible to differentiate electrolytic hydrogen or a mix of electrolytic hydrogen with hydrogen of other origin with higher certainty. Further, it is possible to detect grey or blue hydrogen but it is not possible to distinguish grey from blue hydrogen. Further, the electrolytic hydrogen can also be purple, pink or yellow hydrogen.
Preferably, in a fourth embodiment the step of assessing from the sample the origin of the hydrogen gas comprises:
By the assessment procedure of the fourth embodiment a further improved assessment of electrolytic hydrogen is possible with better certainty based on the additional detection of isotopes, preferably deuterium. In this embodiment it is possible to differentiate electrolytic hydrogen from a mix of electrolytic hydrogen with hydrogen of other origins with even higher certainty. This embodiment is based on the recognition that isotopes of hydrogen, particularly deuterium, are highly reduced in the hydrogen derived solely from water by electrolysis compared to deuterium in hydrogen derived at least partly from natural gas.
Further, it is possible to detect gray or blue hydrogen but it may not be possible to fully distinguish gray from blue hydrogen. Further, the electrolytic hydrogen can also be purple, pink or yellow hydrogen.
Preferably, the step of sampling of the quantity of hydrogen gas comprises one or more of the following analyses:
Preferably, the step of sampling of the quantity of hydrogen gas comprises:
Preferably, the step of certifying the origin of the hydrogen gas is done in an authenticated immutable manner. Thus, the certification step is done preferably fully automatic without the possibility for manipulation.
The above-mentioned problem is also solved by a system for assessing and certifying the origin of hydrogen, wherein the origin of hydrogen describes the of the hydrogen, the system comprises a sampling device, for sampling a quantity of hydrogen gas; an assessing device, for assessing from the sample the origin of the hydrogen; and a certifying device, for certifying the origin of the hydrogen.
Preferably, the sampling device comprises a chromatography device, for performing chromatography of the sample of hydrogen gas; and/or a spectroscopy device, for performing spectroscopy of the sample of hydrogen gas; and/or an optical analysis device, for an optical analysis of the hydrogen gas.
Preferably, the optical analysis device comprises a laser absorption device.
Preferably, the chromatography device comprises a gas chromatography device coupled with pulsed discharge helium ionization detector (GC-PDHID) or a gas chromatography coupled with thermal conductivity detector (GC-TCD). The gas chromatograph coupled with a pulsed discharge helium ionization detector (GC-PDHID) relies on the ionization of compounds by a plasma of helium (done by a pulsed DC discharge). In a GC-TCD gas chromatography device a thermal conductivity detector (TCD) measures the difference of thermal conductivity between the pure carrier gas (usually hydrogen or helium) and the carrier gas with sample compounds with a Wheatstone bridge. The temperature of a filament changes in presence of the sample compounds, leading to a variation of the resistance and of the voltage.
A GC-PDHID gas chromatography device or a GC-TCT gas chromatography device is particularly capable to measure the amount of nitrogen, methane and carbon monoxide in hydrogen.
An optical analysis device preferably comprises an optical spectroscopy device. Optical spectroscopic methods are an alternative to chromatographic methods for hydrogen analysis. In these methods, the intensity of light at a specific wavelength after absorption by matter is measured. The wavelength is typically selected to be specific to the selected chemical compound but some interference might exist. Several different spectroscopic methods can be used including cavity ring-down spectroscopy (CRDS), optical feedback cavity enhanced absorption spectroscopy (OFCEAS), Fourier transform infrared spectroscopy (FTIR), and laser-based direct absorption spectroscopy (DAS).
In CRDS, the light source is a laser emitting at a specific wavelength in an optical resonator composed of two reflective mirrors. The decay time until the light reaches a fraction of its initial intensity is measured. This time decreases when the concentration of the compound absorbing the wavelength increases. This technique allows sensitive detection, down to ppt, due to a high path length of typically several kilometers. However, the analytes which can be measured are limited by the available laser and mirrors wavelengths.
Optical Feedback Cavity Enhanced Absorption Spectroscopy (OFCEAS) is a variant of CRDS with a long optical path at low pressure, below 100 mbar absolute, enabling sampling at low pressure and a reduction of the needed sample volume. Analysis over a range of wavelengths can be performed quickly. With OFCEAS it is particularly possible to optically measure methane and carbon monoxide in hydrogen.
The paper Review and Survey of Methods for Analysis of Impurities in Hydrogenfor Fuel Cell Vehicles According to ISO 14687:2019 of Beurey C, Gozlan B, Carré M, Bacquart T, Morris A, Moore N, Arrhenius K, Meuzelaar H, Persijn S, Rojo A and Murugan A., Frontiers in Energy Research, February 2021, Volume 8, Article 615149 describes various methods of measuring impurities in hydrogen for fuel cell vehicle applications.
A hydrogen isotope analysis to determine the deuterium (D) content in the hydrogen can be preferably done with a gas chromatography combustion isotope ratio mass spectrometry (GC/C/IRMS) device.
Preferably, the sampling device is capable to perform CO measurement and/or N2 measurement and/or CH4 measurement; and/or isotopes measurement, preferably deuterium measurement.
It can be noted here that the detection process according to the invention can be circumvented, if the of the hydrogen is not electrolytic, by means of increased purification of the hydrogen produced in a process using fossil feedstocks to lower the level of impurities. However, this increases the cost of the produced hydrogen and creates a disincentive for such adulteration. Therefore, this further justifies the present invention.
Preferably, depending on the level of certainty of assessment the following measurements are made:
Therefore, an adaptive system is provided that depending on the desired level of certainty or doubt adds further measuring steps to the sampling of the sample of hydrogen gas.
Preferably, the certifying device provides a digital certificate in an authenticated immutable manner, preferably in form of a blockchain.
The above mentioned problem is also solved by a system as described above for performing the method as described above.
In the following, preferred embodiments of the invention are disclosed by reference to the accompanying figure, in which shows:
In the following, preferred embodiments of the invention are described in detail with respect to the figures.
The sampling step 110 may comprise the sub-steps of:
In a first embodiment the sampling step 110 comprises the sub-step of assessing the occurrence of CO in the sample 112. Based on such a sampling the origin of the hydrogen gas can be assessed according the logic of Table 2:
In a second embodiment, the sampling step 11o comprises the sub-steps of assessing the occurrence of CO in the sample 112 and assessing the content of N2 in the sample 114. Based on such a sampling the origin of the hydrogen gas can be assessed according the logic of Table 3:
In a third embodiment, the sampling step 110 comprises the sub-steps of assessing the occurrence of CO in the sample 112, assessing the content of NZ in the sample 114, and assessing the occurrence of CH4 in the sample. Based on such a sampling the origin of the hydrogen gas can be assessed according the logic of Table 4:
In a fourth embodiment, the sampling step 110 comprises the sub-steps of assessing the occurrence of CO in the sample 112, assessing the content of N2 in the sample 114, assessing the occurrence of CH4 in the sample, and assessing the ratio of deuterium to hydrogen in the sample. Based on such a sampling the origin of the hydrogen gas can be assessed according the logic of Table 5:
Where + and ++ indicate increased certainty in the determination that the hydrogen does not originate from electrolysis or is from multiple origins.
The threshold TD of deuterium D in the hydrogen be preferably a value in the range of 30-140 ppmmol, 40-100 ppmmol, 50-75 ppmmol or similar as determined for the specific location and application, with TD being defined as the ratio of number of mol of deuterium to the number of mol of hydrogen (protium). Other ratio can also be used for instance normalized ratio of deuterium/hydrogen proportion compared to the deuterium/hydrogen proportion in see water.
Preferred specific deuterium thresholds TD may be 30, 40, 50, 60, 70, 80, 90, 100, 110 or 120 ppmmol. Particularly preferred is a deuterium threshold of 50 ppmmol. As per the article “Deuterium separation by combined Electrolysis Fuel cell, Energy (2018), doi:10.1016/j.energy.2018.02.014”, the deuterium content of hydrogen originating from electrolysis is significantly reduced (divided roughly per 8) compared to the deuterium content of water itself (150 ppmmol/8=19 ppmmol) whereas the deuterium content of hydrogen originating from fossil feedstocks contains a higher proportion of deuterium coming from the fossil feedstock itself and from water (approximately 150 ppmmol) through the water gas shift reaction.
Preferably, depending on the degree of certainty that is desired with respect to the origin of the hydrogen, further rare impurities generated by fossils processes like Helium, Arsenic, Argon can be determined to enforce the probability of detecting not electrolytic hydrogen.
The certifying step 130 certifies the origin of the assessed hydrogen preferably in an authenticated immutable manner. Thus, as digital smart certificate 50, for example in the form of a blockchain 52 may be used for such a certification (see
The sampling device 10 receives a quantity of hydrogen gas 40 and performs measurements on the hydrogen gas 40 to determine impurities that are characteristic for the or origin of the hydrogen.
To perform such measurements the sampling device 10 may comprise a chromatography device 12, for performing chromatography of the sample of hydrogen gas. Preferably the chromatography device 12 is a GC-PDHID gas chromatography device or a GC-TCT gas chromatography device, as such gas chromatography devices are capable to measure the amount of nitrogen, methane and carbon monoxide in the hydrogen sample 40.
Further, the sampling device 10 may comprise a spectroscopy device 14, for performing spectroscopy of the sample of hydrogen gas. Several different spectroscopic methods can be used including cavity ring-down spectroscopy (CRDS), optical feedback cavity enhanced absorption spectroscopy (OFCEAS), Fourier transform infrared spectroscopy (FTIR).
Further, the sampling device may comprise an optical analysis device 16, for an optical analysis of the hydrogen gas. Such an optical analysis device 16 may comprise a laser absorption device. Particularly, a laser-based direct absorption spectroscopy (DAS) device can be used to sample the hydrogen for impurities.
The sampling results are transmitted from the sampling device 10 to the assessing device 20. The assessing device comprises at least one calculation means 22, which can be a processor, computer, cloud computing device, or the like, which interprets the sampling results and determines the origin of the hydrogen according a specific logic as shown in the Tables 2 to 4.
The origin of the sampled hydrogen 40 is transmitted from the assessing device 20 to the certifying device 30. The certifying device 30 also comprises at least one calculation means 32, which can be a processor, computer, cloud computing device, or the like. The certifying device 30 certifies the origin of the hydrogen gas, by providing a digital certificate in an authenticated immutable manner. Preferably, certifying device 30 calculates the digital smart certificate 50 which is contained within an electronic data file, for example in the form of a blockchain 52.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2021/061365 | 12/6/2021 | WO |
