Method and device for identifying non-electrolysis hydrogen

Abstract

The invention relates to a method for identifying non-electrolysis hydrogen, comprising the steps of: providing (S20) a hydrogen sample (12); checking (S30) whether the sample (12) has a target substance, wherein the target substance is a substance of the following target groups: hydrocarbons, carbon-containing gases, sulphur-containing gases, volatile amines, oxygenates or formates; defining (S14) a series of non-target groups, wherein each non-target group has at least one non-target substance, wherein the non-target substance is characteristic of a transport-related contamination of the sample (12), wherein the transport-related contamination is in particular characteristic of a use of lubricants, plastic seals and / or external air for hydrogen transport; updating (S16) the target groups by subtracting the defined series of non-target groups from the previous target groups, and categorising (S40) the sample (12) as non-electrolysis hydrogen if the sample (12) has the target substance. The invention relates to a corresponding device (1).

Description

[0001] Description

[0002] Method and apparatus for identifying non-electrolysis hydrogen

[0003] The present invention relates to a method and apparatus for identifying non-electrolysis hydrogen.

[0004] The regenerative and sustainable production of molecular hydrogen, H2, for industrial or end users (hereinafter referred to as hydrogen production) is an essential building block of the energy transition. In this context, it is common practice to categorize hydrogen according to its production process using color coding. For example, so-called “grey hydrogen” is produced from fossil feedstocks, for example by steam reforming natural gas, whereby the resulting carbon dioxide is released into the Earth’s atmosphere. “Blue hydrogen” is similar to grey hydrogen and is also of fossil origin but is produced by steam reforming, whereby the resulting carbon dioxide is captured during the production process so that it does not enter the Earth’s atmosphere.Turquoise hydrogen is produced by methane pyrolysis, producing solid carbon which – similar to blue hydrogen – is further processed in such a way that no carbon dioxide enters the Earth's atmosphere.

[0005] Green hydrogen is produced exclusively using renewable or sustainably produced energy and water through an electrolysis process, making it a particularly sustainable form of hydrogen production. It is therefore called electrolysis hydrogen.

[0006] It is known to distinguish the source of hydrogen atoms based on fossil or non-fossil origin using an isotope method. This is based on the idea that the isotope ratios differ due to isotope fractionation processes during long fossil storage compared to the isotope ratio of surface water, which is typically used for electrolysis. This makes it fundamentally possible to distinguish, for example, electrolysis hydrogen from blue hydrogen. However, isotope detection is very complex and costly in terms of measurement technology.

[0007] Currently, no methods or devices are known for identifying non-electrolysis hydrogen or hydrogen of fossil origin that is delivered to a consumer on a large-scale or industrial basis.

[0008] Summary of the invention

[0009] Based on the known prior art, it is an object of the present invention to provide an efficient method and an efficient apparatus for identifying non-electrolysis hydrogen.

[0010] The problem is solved by a method having the features of claim 1. Advantageous further developments emerge from the subclaims, the description and the figures.

[0011] Accordingly, a method for identifying non-electrolysis hydrogen using target substances from target groups is proposed, comprising the steps:

[0012] - Defining a series of non-target groups, each non-target group comprising at least one non-target substance, the non-target substance being characteristic of a transport-related contamination of the sample, the transport-related contamination being particularly characteristic of the use of lubricants, plastic seals, and / or external air for hydrogen transport; - Updating the target groups by subtracting the defined series of non-target groups from the previous target groups;

[0013] - Providing a hydrogen sample;

[0014] - Check whether the sample contains a target substance, where the target substance is a substance from the following target groups: hydrocarbons, carbon-containing gases, sulphur-containing gases, volatile amines, formates or oxygenates;

[0015] - Categorize the sample as non-electrolysis hydrogen if the sample contains the target substance.

[0016] In this context, non-electrolysis hydrogen refers to a mixture of substances that is traded commercially as molecular hydrogen, i.e., H2, and which, according to the examples and definitions mentioned above, is typically not classified as electrolysis hydrogen. Thus, "non-electrolysis hydrogen" includes all mixtures consisting essentially of hydrogen that are produced from coal, natural gas, or biomass.

[0017] The step of “providing a hydrogen sample” can, for example, be performed by taking the sample from a hydrogen supply intended for a consumer. Furthermore, the sample can also remain within the hydrogen supply intended for a consumer, i.e., not be taken, and can be provided by providing optical or physical access to the sample within the hydrogen supply. For example, optical access can be provided by means of a window on a measuring chamber or on a hydrogen supply line. Physical access can be provided by arranging a sensor within the measuring chamber or the hydrogen supply line so that the sensor is in physical contact with the sample.

[0018] The step of "checking whether the sample contains a target substance" can be performed using a measuring device designed to detect the target substance in the sample. Because the target substance to be detected in the sample comes from one of the aforementioned target groups, it is particularly easy to conclude that the production process is non-electrolytic, as explained below.

[0019] Electrolysis hydrogen may contain water, H2O, in the course of so-called wet electrolysis or oxygen, O2, due to carryover of anode gases, but typically does not contain any substance from the target groups mentioned above.

[0020] In the course of the present invention, it was recognized that non-electrolysis hydrogen production processes cause characteristic by-products in the hydrogen. Subsequently, it was investigated which by-products non-electrolysis hydrogen production processes have in addition to the main product, hydrogen. The aforementioned target groups were derived from this investigation. It was recognized that every non-electrolysis hydrogen production process characteristically has certain by-products that remain in the product in detectable amounts even despite hydrogen purification. This can be attributed to a further finding, namely that purification to separate the by-products is not complete on an industrial scale, as the following example illustrates.

[0021] For example, the purification of hydrogen for specific industries or applications may be regulated by standards. For example, the ISO 14687-3 standard allows comparatively high tolerances for byproducts in hydrogen for stationary fuel cells. Furthermore, ISO 14687-2, in contrast, only specifies limited maximum levels of byproducts in hydrogen for PEM fuel cells in the automotive sector. In the course of the present invention, it was recognized that conventional purification processes are designed to meet such or comparable standards and specifications, so that the purification processes typically do not deliver 100% pure H2.

[0022] The target groups are further specified below using examples. The target group "hydrocarbons" includes, in particular, pure carbon-hydrogen compounds such as methane, which, for example, has not been converted in natural gas steam reforming or methane pyrolysis. In this context, "pure carbon-hydrogen compounds" refers in particular to elemental hydrocarbons, i.e., compounds consisting only of carbon and hydrogen, such as alkanes and alkenes. Thus, the target group "hydrocarbons" includes, for example, ethane, propane, butane, and pentanes.

[0023] The target group "carbon-containing gases" includes, in particular, carbon oxides, i.e., oxocarbons, such as carbon monoxide or carbon dioxide. In other words, the target group "carbon-containing gases" can include oxocarbons, i.e., compounds composed exclusively of carbon and oxygen. In the case of steam reforming, a typical combined CO + CO2 content after hydrogen purification is approximately 10 ppmV.

[0024] The target group "sulfur-containing gases" includes, in particular, hydrogen sulfide and sulfur dioxide. Sulfur-containing substances can be present in natural gas or coal, so sulfur-containing gases can be indicative of a fossil, i.e., non-electrolysis, hydrogen source. Sulfur-containing gases can also be indicative of methane produced from biomass to be processed into hydrogen by methane reforming or methane pyrolysis. Hydrogen produced from biomass also counts as non-electrolysis hydrogen and is sometimes referred to as orange hydrogen.

[0025] The target group "volatile amines" includes amines that typically emit a fishy odor and are the result of amine scrubbing for the targeted removal of carbon dioxide or hydrogen sulfide, such as methylamine, dimethylamine, and trimethylamine. Amine scrubbing is typical for non-electrolysis hydrogen production processes in which the hydrogen atoms originate from coal, fossil methane, or biomass methane.

[0026] The target group "oxygenates" includes, for example, formaldehyde, acetaldehyde, and formic acid esters. In the course of the present invention, it was discovered that formaldehyde and / or formates can be present as byproducts in non-electrolysis hydrogen in the case of methane production from biomass.

[0027] As described above, the sample is tested to determine whether it contains a target substance, which is a substance from the aforementioned target groups. In this context, a "substance" is understood to mean a substance or chemical compound.

[0028] Thus, testing can be intended for a single target substance. Furthermore, testing can be intended for a series of target substances that originate from one or more of the target groups.

[0029] For example, testing may be carried out only for methane or only for sulfur-containing gases. In this way, testing can be carried out quickly and easily, since the presence of methane or the presence of a sulfur-containing gas, according to the above findings, implies that the sample originates from non-electrolysis hydrogen. According to another example, testing may be carried out for CO2 and for a volatile amine. In this example, two possibly supplementary target groups are tested: If, for example, no CO2 could be detected in the sample, this could be due to thorough amine washing of hydrogen produced from fossil sources, so that additional testing for a volatile amine can be carried out downstream. Analogously, testing for hydrogen sulfide and a volatile amine may be provided in another example.

[0030] In other words, the testing can concern any combination of the target substances or substances from the target groups, whereby a combined test can be carried out in parallel, i.e. essentially simultaneously, or sequentially, i.e., for example, subsequently.

[0031] The step of "categorizing the sample as non-electrolysis hydrogen if the sample contains the target substance" can be performed, for example, by assigning the attribute "non-electrolysis" or "positive" to a data set corresponding to the sample or to the hydrogen delivery being tested, where "positive" indicates the detection of one of the accompanying products described above.

[0032] Furthermore, the procedure may include the following step:

[0033] - Repeating the test step n times for each additional target substance to test the sample for a series of n target substances; where n is greater than or equal to 2.

[0034] For example, the sample can be tested in parallel for several target substances in a first test step, for example CO and CO2. In a subsequent second test step, several target substances can again be tested in parallel, for example H2S and SO2, volatile amines. And in a subsequent third test step, volatile amines can be tested. In the case of sequential testing, the same sample can always be tested. Additionally or alternatively, a new hydrogen sample can always be provided for each sequential test. Furthermore, a combination of the procedures described above can be used, for example by carrying out the first and second test steps for a first provided sample and the third test step for a second provided sample.

[0035] Furthermore, it can be provided that a planned three-fold repetition of the testing step is aborted in the case of a positive sample after the first or second test step and the sample is immediately categorized as non-electrolysis hydrogen.

[0036] Thanks to the procedures described above, the method can be particularly easily designed and adapted for a specific set of target groups or target substances as well as for a sensor arrangement to be designed to carry out the test steps.

[0037] Furthermore, the procedure may include the following steps:

[0038] - Defining a reference pattern which specifies a range of the target substance, and in particular a range of the other target substances, in the sample; and

[0039] - Linking the reference sample to at least one non-electrolysis hydrogen production process for which the reference sample is characteristic.

[0040] According to the above step "Defining a Reference Pattern," the reference pattern can specify the range of concentrations of a single target substance in the sample. Additionally or alternatively, the reference pattern can specify the range of concentrations of multiple target substances in the sample.

[0041] The latter is particularly the case if the "testing" step is to be repeated for further, i.e., multiple, target substances. In any case, the reference sample must be defined by selecting target substances and respective proportion ranges in such a way that the reference sample is characteristic of a non-electrolysis hydrogen production process, i.e., for a specific form of non-electrolysis hydrogen, according to the findings described above.

[0042] In the subsequent "linking" step mentioned above, the reference sample is linked to at least one non-electrolysis hydrogen production process for which the reference sample is characteristic. In this way, if the sample tests positive, i.e., if the sample contains one or more target substances, one or more possible non-electrolysis production processes can be deduced.

[0043] Following on from one of the above examples, in the case of steam reforming, a typical combined proportion of CO and CO2 after hydrogen purification can be approximately 10 ppmV. Accordingly, for example, a reference sample can be linked to the fossil-based production process "steam reforming," which specifies a proportion range of the target substance CO from 0.01 to 10 ppmV and a proportion range of the target substance CO2 from 0.01 to 10 ppmV in the same sample. The ppmV specification refers to the volume mixing ratio parts per million. For example, 8 ppmV of CO in hydrogen means 8 microliters of CO per liter of hydrogen. As an alternative to ppmV, pg / g (micrograms per gram) can be used to specify a proportion or concentration of a byproduct in hydrogen.

[0044] Furthermore, a reference sample can be linked to the non-electrolysis hydrogen production process "methane from biomass", for example via reforming using supercritical water or via pyrolysis, which specifies a content range of the target substance formaldehyde from 0.001 to 100 ppmV, in particular from 0.01 to 10 ppmV. Furthermore, several reference samples can be combined and this combination can be linked to a specific non-electrolysis hydrogen production process.

[0045] In addition, the procedure may include the following step:

[0046] - Repeat the "Define" and "Link" steps above to create a series of linked reference patterns.

[0047] Furthermore, the procedure may include the following steps:

[0048] - Determining the proportion of the target substance in the sample;

[0049] - comparing the determined proportion with the proportion range of the reference sample; and

[0050] - Assigning the sample to at least one non-electrolysis hydrogen production process, provided that the determined proportion lies within the proportion range of the reference sample.

[0051] Additionally, the method may comprise the step of repeating the above steps of "matching" and "assigning" for the set of linked reference patterns.

[0052] In other words, "determining a proportion of the target substance in the sample" refers to determining a concentration of the proportion of the target substance in the sample by means of a measuring device or by means of a gas sensor.

[0053] Thanks to the procedure described above, a large number of relevant non-electrolysis hydrogen production processes can be linked to reference samples, so that one or more possible non-electrolysis hydrogen types can be easily determined via determination, comparison and assignment.

[0054] According to a further development, the proportion range of the target substance in the sample can be 0.001 to 100 ppmV, in particular 0.01 to 1 ppmV. In particular, the proportion range can be determined, as described above, based on the expected concentrations of one of the by-products characteristic of a non-electrolysis hydrogen production process. In this way, a specific proportion range can be determined for each target substance, and thus for each by-product, for a reference sample. For example, a certain target substance can be specified in different reference samples, each with different proportion ranges. In this way, the reference samples can be individually adapted to the respective non-electrolysis hydrogen production process.

[0055] Furthermore, the step “providing a hydrogen sample” may include:

[0056] - continuous flow of sample gas past a measuring device.

[0057] Additionally, the "Check" step may include:

[0058] - continuous measurement of the continuously flowing sample gas.

[0059] In other words, the sample can be passed through the measuring device in a continuous hydrogen gas stream, while the gas stream is continuously measured, thus checking whether the sample in the form of the gas stream contains the target substance. Continuous measurement is understood here to mean that measurements or measurement events can be recorded continuously or discretely without the need to actively adjust the measuring arrangement of the measuring device and sample. For example, taking a sample from a hydrogen pipe or storage tank and feeding the sample into a separate measuring chamber represents active adjustment in the above sense and typically does not allow for continuous measurement in the above sense.

[0060] Thanks to the procedure described above, the sample can be tested continuously and can therefore be used in particular for hydrogen deliveries that are continuously delivered to a consumer via pipeline.

[0061] Furthermore, the procedure may include the following step:

[0062] - Tracking categorized samples using a hydrogen certification module, in particular a blockchain module for hydrogen certification.

[0063] In other words, the "Categorizing the Sample" step can result in a categorized measurement event that is transferred to a data storage system of a hydrogen certification module or a blockchain module for hydrogen certification for the purpose of hydrogen certification. This can be done, in particular, by linking the categorized measurement event to the sampled hydrogen delivery.

[0064] Thus, the categorized measurement event is permanently saved and inalterably linked to the sampled hydrogen delivery. This makes the categorization of the sample and its results transparent and traceable for other recipients, such as the hydrogen supplier, the hydrogen consumer, authorities, and / or certification bodies.

[0065] Furthermore, it can be provided that the target substance is one of the following substances: CH4, CO, CO2, H2S, SO2, methylamine, dimethylamine, trimethylamine or formaldehyde.

[0066] Furthermore, the step of "checking whether the sample contains a target substance" can be carried out using an absorption spectroscopic method in the near (NIR) or mid (MIR), in particular with diode laser absorption spectroscopy, which is also referred to as tunable diode laser absorption spectroscopy, hereinafter referred to as "TDLAS". These methods are particularly suitable for detecting several gases selectively, i.e., without mutual influence on the measurement result, as well as precisely with regard to the quantification of the gas concentration.

[0067] The above-mentioned object is further achieved by a device having the features of claim 9.

[0068] Advantageous developments of the method will become apparent from the present description and the figures. Accordingly, a device for identifying non-electrolysis hydrogen using target substances from target groups is proposed, comprising

[0069] - a measuring device designed to detect a target substance in a hydrogen sample,

[0070] - an evaluation unit communicatively connected to the measuring device, which is set up to categorize the sample as non-electrolysis hydrogen if the target substance is detected in the sample by means of the measuring device, wherein the target substance is a substance from the following target groups: hydrocarbons, carbon-containing gases, sulfur-containing gases, volatile amines, formates or oxygenates, wherein the evaluation unit is set up to define a series of non-target groups, wherein each non-target group has at least one non-target substance, wherein the non-target substance is characteristic of a transport-related contamination of the sample, wherein the transport-related contamination is in particular characteristic of the use of lubricants, plastic seals and / or external air for hydrogen transport;and to update the target groups by subtracting the defined series of non-target groups from the existing target groups.;

[0071] The findings, technical effects, and advantages explained above for the proposed method apply equally to the proposed device. This particularly concerns the specification of the target substances and target groups.

[0072] Furthermore, the measuring device can have a measuring arrangement or a combination of several measuring arrangements from the following list: infrared optical gas sensor, solid-state gas sensor, Nernst sensor, catalytic sensor, gas chromatograph, quadrupole mass spectrometer, ion mobility spectrometer.

[0073] Furthermore, the device may comprise:

[0074] - a cavity for storing or conveying hydrogen for a consumer, wherein the cavity is designed in particular in the form of a hydrogen storage tank or a hydrogen supply line, and

[0075] - a measuring chamber coupled to the measuring device, which can be fluidically connected to the cavity.

[0076] In this context, a cavity is defined as a volume or space in which a measurement can be taken on a sample. This includes a pipeline, where the sample can be located in a designated section, volume, or space of the pipeline at the time of measurement.

[0077] In this context, the measuring chamber is understood to be a space in which the sample can be provided so that the sample can be tested using the measuring device. The measuring chamber can, for example, be an open space within the cavity for storing or conveying hydrogen. Additionally or alternatively, the measuring chamber can be a space separate from the cavity, i.e., a separate measuring chamber outside the cavity.

[0078] The measuring device can be coupled to the measuring chamber, for example, by having sensors arranged on or within the measuring chamber. Furthermore, the measuring device can be coupled to the measuring chamber by allowing radiation emitted or received by the measuring device to pass through the measuring chamber. The fluidic connection of the measuring chamber to the cavity includes both arrangements in which the measuring chamber is arranged in the cavity by design and fluidically connected, as well as arrangements in which the measuring chamber is temporarily connected to the cavity via a temporary connecting line for the purpose of providing the sample.Furthermore, this concerns arrangements in which the sample is taken from the cavity and fed to the measuring chamber by means of a separate transport vessel, whereby the fluidic connection between the cavity and the transport vessel is separated before the transport vessel is fluidically connected to the measuring chamber.

[0079] Additionally or alternatively, the device may comprise an optically transparent window that can be arranged on the cavity. The aforementioned hydrogen supply line is understood, in particular, to be a pipeline through which a supply of hydrogen is to be delivered to any consumer. The consumer may be a person or a technical unit that is to obtain electrolysis hydrogen from a hydrogen supplier.

[0080] Because the optically transparent window can be arranged on the hydrogen supply line, the above-described continuous measurement of the continuously flowing sample gas can be performed, particularly using an infrared optical measuring device. This eliminates the need to install a sensor inside the hydrogen supply line, which could potentially expose the sensor to contamination.

[0081] Furthermore, the optically transparent window can be arranged on the hydrogen storage tank, allowing the use of an infrared optical measuring device. This way, for example, sampling or the provision of a separate measuring chamber can be dispensed with.

[0082] Alternatively, the cavity may not be included in the device. Generally, and especially in this case, the device may comprise an interface device for coupling the measuring device to the cavity. The interface device may comprise the optically transparent window and / or a device for sampling gas.

[0083] Furthermore, the device can comprise a protective housing in which the measuring device and / or the evaluation unit is / are accommodated. The protective housing can be sealed. Additionally or alternatively, the protective housing can be sealed with a lead seal. Furthermore, the device, in particular the entire device, can be enclosed by the protective housing.

[0084] Thanks to the protective enclosure, the risk of unintentional or deliberate tampering with the measuring device, the evaluation unit, or the entire device can be mitigated. Sealing or lead-sealing allows for evidence of any unintentional tampering attempt.

[0085] Furthermore, the device can have a communication unit communicatively connected to the evaluation unit, which is configured for wireless or wired data communication. In particular, the evaluation unit can be configured to store a series of measurement events in a measurement log. The communication unit can be configured to communicate individual measurement events or the measurement log to external receivers. Such an external receiver can be the aforementioned hydrogen certification module or blockchain module, or a receiving module of one of the aforementioned receiver groups. Thus, the result of the sample categorization can be communicated to external receivers or the receiver groups. In this way, the identification or detection of non-electrolysis hydrogen can be transparent and traceable, and thus particularly robust.

[0086] According to a further development, the protective housing can have an opening sensor for detecting the opening of the protective housing. Furthermore, the opening sensor can be communicatively connected to the evaluation unit and / or the communication unit. In this way, an unwanted tampering attempt can be detected instantly. Furthermore, a detected tampering attempt can be logged or communicated to the receiving circuits.

[0087] Furthermore, the device can comprise a recording device communicatively connected to the measuring device for logging and storing measurement data from the measuring device. In particular, the recording device can comprise a local, non-volatile data memory. Furthermore, the recording device can be provided in a separate protective housing that protects the recording device, for example, against fire, vibrations, water, and electric shock. In other words, the recording device can be provided analogously to a so-called "flight recorder." The recording device can further be configured to log and store the manipulation attempts described above, i.e., be coupled to the opening sensor. Thanks to the recording device, measurement data can be stored robustly and securely even in the event of technical malfunctions or manipulation.

[0088] Furthermore, the device can

[0089] A power supply device configured to supply the device with electrical energy. The power supply device can be configured as a primary main power supply device or as a secondary power supply device that, in the event of a failure of an external main power supply device, supplies the device with electrical energy as an auxiliary device, for example, in the form of an emergency generator. In particular, the power supply device can be arranged within the protective housing. In this way, the device can be provided as a self-sufficient unit that is also particularly tamper-proof.

[0090] Furthermore, the measuring device can have a tunable laser diode, i.e. a so-called Tunable Diode Laser (short "TDL"). In particular, the

[0091] Measuring device must be set up to apply the TDLAS mentioned above.

[0092] Short description of the characters

[0093] Preferred further embodiments of the invention are explained in more detail in the following description of the figures. These schematically show:

[0094] Figure 1 Method for identifying non-

[0095] Electrolysis hydrogen according to an embodiment;

[0096] Figures 2a, b each show an embodiment of a device for identifying non-electrolysis hydrogen; and

[0097] Figures 3-d show sections of further examples of a device for identifying non-electrolysis hydrogen; and

[0098] Figure 4: Sensitivities achievable using TDLAS for relevant target substances.

[0099] Detailed Description of Embodiments Embodiments are described below with reference to the figures. Identical, similar, or equivalent elements in the different figures are provided with identical reference symbols, and a repeated description of these elements is partially omitted to avoid redundancies.

[0100] Figure 1 illustrates a method for identifying non-electrolysis hydrogen. More specifically, Figure 1 shows various possible configurations of the method.

[0101] In step S10, a reference pattern is defined that specifies a range of the concentrations of a target substance, and in particular a range of the concentrations of other target substances, in the sample. The target substance or the other target substances is a substance from the following target groups: hydrocarbons, carbon-containing gases, sulfur-containing gases, volatile amines, or oxygenates. In particular, a target substance can be one of the following substances: CH4, CO, CO2, H2S, SO2, methylamine, dimethylamine, trimethylamine, or formaldehyde.

[0102] After step S10, step S12 or step S20 can optionally be performed. In step S12, the reference pattern is linked to at least one non-electrolysis hydrogen production process for which the reference pattern is characteristic. In the course of the present invention, various non-electrolysis hydrogen production processes were investigated for typical byproducts. From this investigation, the above-mentioned target groups or target substances were derived, which correspond to the typical byproducts of non-electrolysis hydrogen.

[0103] As explained above, so-called green hydrogen is produced by electrolysis. Here, water is electrolytically split through redox reactions at the anode and cathode:

[0104] Cathode: 2 H2O + 2e~ -> H2 + 2 OH~ Anode: 4 OH -> 2 H2O + 02 + 4 e~ Electrons are released at the cathode and taken up again by the anode.

[0105] In the overall reaction, water thus produces almost exclusively molecular hydrogen, H2, and molecular oxygen, O2, according to the overall reaction: 2 H2O -> 2 H2 + O2. Electrolysis is carried out with ultrapure, demineralized water, so that in addition to the main product, H2, only H2O (in the case of wet electrolysis) and small amounts of O2 due to carryover of anode gases are to be expected. This applies to alkaline electrolysis, polymer electrolyte membrane electrolysis (PEM), and high-temperature electrolysis.

[0106] It is therefore expected that green hydrogen (apart from water and oxygen) does not contain any byproducts, in particular no substances from the target groups or none of the target substances.

[0107] Furthermore, in the course of the present invention, the non-electrolysis hydrogen production processes described below were investigated.

[0108] For example, hydrogen can be produced from fossil methane, such as natural gas, by steam reforming. In this process, methane is decomposed into CO and H2 by added heat (endothermic process) and water according to the following equation: CH4(g) + H2O(g) <-> CO(g) + 3 H2(g) The required reaction enthalpy can also be generated by partial oxidation; this process is exothermic: 2 CH4(g) + O2(g) <-> 2 CO(g) + 4 H2(g) To increase the hydrogen yield, the resulting carbon monoxide is converted into carbon dioxide and further hydrogen in a further reaction (water gas shift reaction): CO(g) + H2O(g) <-> CO2(g) + H2(g) The CO content can be reduced to 0.6 to 1.5 vol.% depending on the operating mode of the water gas shift reactor. Thus, small amounts of CO and unconverted CO2 are still present as byproducts in the so-called grey hydrogen, i.e. non-electrolysis hydrogen.Furthermore, it can be deduced from the above reaction equations that the grey hydrogen may contain unreacted CH4.

[0109] Furthermore, it is possible to subject gray hydrogen to an amine scrub to remove the unreacted CO2 as completely as possible. In the course of the present invention, it was discovered that gray hydrogen, even after an amine scrub, still contains approximately 10 ppmV CO + CO2. Furthermore, when defining the target groups or target substances, the invention takes advantage of the fact that non-electrolytically purified hydrogen, purified by amine scrubbing, generally still contains traces of volatile amines. Furthermore, it was discovered that fossil methane contains sulfur-containing components, the derivatives of which are H2S and SO2. X , can be detected in small amounts in non-electrolysis hydrogen even after purification.

[0110] Furthermore, non-electrolysis hydrogen can be produced, for example, from methane obtained from biomass. Such biomass can be solid materials such as wood, sewage sludge, or municipal waste, which cannot be vaporized, so reforming takes place under different conditions than for methane from natural gas.

[0111] For example, in the case of biomass, reforming can be carried out using supercritical water over a heterogeneous catalyst at 250–300 bar and 400–550 °C with a large excess of water. In this case, the byproducts mentioned in fossil methane reforming are to be expected in the hydrogen. Furthermore, a wide range of simple hydrocarbons and oxygenates, including formaldehyde and formates, are to be expected due to the thermal decomposition of the biomass. Accordingly, these additional byproducts can be considered for the definition of the target groups or target substances.

[0112] Furthermore, non-electrolysis hydrogen can be produced, for example, by methane pyrolysis, particularly thermally or using the Kvarner process. This applies, in turn, to both fossil methane and methane from biomass.

[0113] In thermal methane pyrolysis, thermal energy can be added to the methane gas, for example, by introducing the methane gas at the bottom of an upright bubble column reactor and allowing it to rise as bubbles in liquid metal within the reactor. Pyrolysis occurs as the bubbles rise. When the bubbles reach the top of the liquid metal reactor, they burst and release a mixture of hydrogen, (solid) carbon, and residual methane. The residual methane is then separated or the hydrogen is purified.

[0114] According to the main reaction equations of the Kvarner process or the bubble column reactor, the formation of hydrogen and carbon, which are the main components in the product, is described as follows:

[0115] Reaction equation: CH4-> C + 2 H2

[0116] In the general case: C n H m + Energy -> n C + H2

[0117] However, in the course of the present invention it was recognized that due to the use of natural gas as a starting material, sulfur-containing gases, in particular H2S and S0 x, are to be expected in the product stream, and furthermore, that unconverted CH4, other hydrocarbons, and H2O are typically present in the product stream. Furthermore, it was recognized that the separation or purification of these substances is not 100% complete, so they are to be expected as byproducts in this type of non-electrolysis hydrogen. Accordingly, these aforementioned byproducts can be considered for the definition of the target groups or target substances.

[0118] Referring again to Figure 1, a step S14 is carried out, comprising defining S14 a series of non-target groups, each non-target group comprising at least one non-target substance, the non-target substance being characteristic of a transport-related contamination of the sample. The transport-related contamination may be characteristic of the use of lubricants, plastic seals, and / or external air for hydrogen transport. Step S14 can be carried out chronologically or logically before, after, or parallel to step S12. Independently of this, the steps of defining S10 and linking S12 can be repeated in a step S13 to generate a series of linked reference patterns.For example, a first reference pattern may be directed to the identification of hydrogen produced by coal gasification, a second reference pattern may be directed to the identification of blue hydrogen, and a third reference pattern may be directed to the identification of turquoise hydrogen (Kvarner process).

[0119] Furthermore, individual non-target substances can be identified, and non-target groups can be inferred from them. Additionally or alternatively, non-target groups can be identified, and specific non-target substances can be derived from them. Step S14 is based on the realization that even electrolysis hydrogen can contain impurities due to transport-related phenomena, which could lead to a false-positive test result, i.e., an unjustified categorization as "non-electrolysis," if these phenomena were ignored. Thus, the method can be made even more robust using step S14.

[0120] For example, the following contaminants can arise in the hydrogen transport chain:

[0121] Traces of hydrocarbons (short to long chain hydrocarbons) that can be introduced into the hydrogen to be transported by lubricants (e.g. during compression) and plastic seals.

[0122] - Significant air components N2, 02or moisture, which can be introduced into the hydrogen to be transported by using previously unventilated pipes, pumps or leaks.

[0123] For example, step S14 can comprise a calibration in which high-purity hydrogen is delivered to the consumer on a test basis via a specific transport chain, with all accompanying products and impurities being detected and analyzed, for example, using high-resolution laboratory equipment. Furthermore, it can be provided that permissible content ranges for the identified non-target substances are determined. For example, silicone oils could be identified as one of the non-target groups, and permissible content ranges can be defined for specific silicone oils. Furthermore, certain long-chain hydrocarbons, which can typically originate from lubricating oils, could be identified as one of the non-target groups, and permissible content ranges for specific long-chain hydrocarbons can be defined for specific lubricating oils.

[0124] After step S14, the target groups are updated in step S16 by subtracting the defined series of non-target groups from the existing target groups. The existing target groups are those from steps S10 and S12, respectively. Furthermore, step S16 may include subtracting the defined series of non-target substances from the existing target substances.

[0125] In other words, in step S16, the set of non-targets can be qualitatively subtracted from the set of targets. Additionally or alternatively, the permitted non-target share ranges newly identified in step S14 can be quantitatively subtracted from the previously defined share ranges (of the targets).

[0126] For example, a lubricating oil used in the transport chain could contain sulfur, such as a lubricating oil for lubricating a pump. The proposed calibration can then be used to detect that—due solely to transport—extremely small amounts, for example, less than 0.5 ppmV, of sulfur-containing gases are present in the electrolysis hydrogen. In step S16, a previously defined range of 0.1 to 100 ppmV for sulfur-containing gases can then be updated to 0.5 to 100 ppmV.

[0127] After step S10, optionally after step S12, S13 or S16, a hydrogen sample 12 is provided S20 for a measuring device 10 in a step S20. With regard to the reference numerals for the device components, reference is made to Figures 2a, b and 3a-d.

[0128] The hydrogen intended for the consumer 52 is supplied by a hydrogen source 50 or supplier 50 (see Figures 2a, b, 3a). The supply takes place by means of a cavity 16 for storing or conveying hydrogen for the consumer 52, wherein the cavity 16 is designed in the form of a hydrogen storage tank 16a (see Figures 2b, 3b, c) or a hydrogen supply line 16b (see Figures 2a, 3a, d). The provision S20 of the sample 12 can take place, for example, by the sample 12 being taken from the hydrogen supply line 16b and being supplied to a separate measuring chamber 18 (see Figure 2a), or by the sample 12 being taken from the hydrogen storage tank 16a and being supplied to the measuring chamber 18 (see Figure 2b).

[0129] Furthermore, the provision S20 can take place while the sample 12 remains in the cavity 16 (see Figures 3a-d). In these cases, the sample 12 or the sample gas flows continuously past the measuring device 10, wherein the measuring device performs a testing S30 or measurement in a measuring section 10d within the cavity 16. For example, an optically transparent window 20, or an input window 20a and an output window 20b (see Figure 3b) can be arranged on the cavity 16, via which the measuring device performs the testing / measurement in the measuring section 10d within the cavity 16.

[0130] Alternatively, the provision S20 can be carried out by the measuring device 10 having a sensor arranged within the cavity for testing / measuring the sample 12.

[0131] After sample 12 is provided S20, the sample is tested in step S30. More precisely, in the simplest variant, the test determines whether sample 12 contains one of the target substances or a substance from the target groups.

[0132] Furthermore, the testing S30 can comprise a more precise measurement, in particular a step S32 determining a proportion of the target substance in the sample 12. Optionally, according to a step S31, the steps S30 and / or S32 can be repeated. In this way, the sample 12 can be examined for several target substances. If this is to be done sequentially, this can of course be done by making a fresh sample available again S20, without this being explicitly shown in Figure 1. After the step S32 determining, a step S34 comparing (S34) the determined proportion with the proportion range of the reference sample takes place, and a step S36 assigning the sample to the at least one non-electrolysis hydrogen production process takes place, provided the determined proportion lies within the proportion range of the reference sample. Optionally, the steps S34 and S36 can be repeated in a step S37 before the downstream step S40.Thus, the comparison S34 and assignment S36 can be carried out accordingly for the several tested or measured samples.

[0133] To carry out steps S32 to S37, further components of the proposed device 1 can be used, in particular an evaluation unit 14 communicatively connected to the measuring device 10 (see Figures 2a, b), which can be configured to carry out step S40 and / or steps S32 to S36.

[0134] After step S30 or after step S36, sample 12 is categorized as non-electrolysis hydrogen in step S40 if sample 12 contains the target substance. In the simplest case, categorization can be performed simply by assigning the attribute "non-electrolysis" or "positive" to a data set corresponding to sample 12 or to the tested hydrogen delivery, where "positive" indicates the detection of one of the accompanying products described above.

[0135] Furthermore, for example, if steps S32 to S36 have been performed, the categorization S40 may include storing further attributes in the data set corresponding to the tested hydrogen delivery in the form of the determined proportion according to S32, the result of the comparison with the reference sample according to S34, or the associated manufacturing process according to S36. After step S40, a step S50 may be performed to track categorized samples 12 using a hydrogen certification module 30, in particular using a blockchain module 30a for hydrogen certification (see Figures 2a, b). In particular, the measurement event described above may be linked to the aforementioned attributes, with the resulting data set being tracked using module 30 or 30a.

[0136] Figures 2a, b each show an embodiment of a device 1 for identifying non-electrolysis hydrogen, wherein the hydrogen according to Figure 2a is supplied to the consumer 52 by means of the supply line 16b described above and the hydrogen according to Figure 2a is supplied to the consumer 52 by means of the storage tank 16a described above.

[0137] In principle, the devices 1 of Figures 2a to 3d are configured to carry out the proposed method. Accordingly, the above description of Figure 1 applies to the examples according to Figures 2a to 3d. To avoid repetition, the following describes in particular those features that were not discussed above or were discussed only briefly. This also applies to Figures 3a-d, which show sections of further examples of a device 1 for identifying non-electrolysis hydrogen.

[0138] The devices 1 according to Figures 2a to 3d have the following in common: The device 1 comprises a measuring device 10, an evaluation unit 14 communicatively connected to the measuring device 10, a communication unit 24 communicatively connected to the evaluation unit 14, and a protective housing 22 in which the measuring device 10 and / or the evaluation unit 14 are accommodated and the communication unit 24 is / are located. The protective housing 22 has an opening sensor 22a for detecting an opening of the protective housing 22. The opening sensor 22a is communicatively connected to the evaluation unit 14 and / or to the communication unit 24.Furthermore, the device 1 comprises a recording device 26 which is communicatively connected to the measuring device 10 for logging and storing measurement data of the measuring device 10, as well as a power supply device (not shown in the figures) which is designed to supply the device 1 with electrical energy, wherein the power supply device is arranged within the protective housing 22.

[0139] The provision S20 is carried out according to Figures 2a, b by sampling using an interface device 32. In the case of the supply pipe 16b, the interface device 32 can be permanently arranged, for example, stationary, on the cavity 16 in the form of the supply pipe 16b. In the case of the storage tank 16a, the interface device 32 can be detachably arranged on the cavity 16 in the form of the storage tank 16a.

[0140] Sample 12 can, for example, contain a quantity of 100-5000 mlN (N=normal conditions) hydrogen, which may contain the accompanying products described above. The device 1 according to Figures 2a, b comprises a measuring chamber 18 containing the measuring device 10. The evaluation unit 24 can comprise a control unit (not shown) or be coupled to a control unit, wherein the evaluation unit 24 or the control unit controls the control of the device 1, in particular the physical sampling and the data processing.

[0141] A selective gas detector, encompassed by the measuring device 10, is arranged in the measuring chamber 18 and measures the proportion or concentration of the aforementioned target substances and / or non-target substances (e.g., contaminants resulting from the transport chain). Before performing a further test / measurement in the measuring chamber, the sample 12 can be released into the environment, recycled, or returned to the cavity 16, in particular the supply line 16b. For this purpose, the device 1, in particular the interface unit 32, can have corresponding gas lines and a pump unit (not shown). Furthermore, the interface unit 32 can be configured to relieve the sample 12 from the comparatively high delivery pressure.In particular, the pressure can be released to a pressure slightly above atmospheric level, as this prevents the potential penetration of ambient air into the measuring chamber 18 and thus measurement errors. Furthermore, the device 1, in particular the interface unit 32, can comprise means for heating said gas lines and the measuring chamber 18. In this way, condensation of slightly less volatile components on the walls of the interface unit 32 and the measuring chamber 18 can be prevented.

[0142] Thanks to the arrangement according to Figure 2b, the checking S30 and categorizing S40 can be carried out in particular before the hydrogen supply stored in the tank 16a is supplied to the consumer, for example by coupling connecting pieces 16c.

[0143] In Figures 2a, b, the device 1 is schematically shown as a dashed box to clarify which components are comprised by the device 1. For example, the protective housing 22 can be sealed and can extend such that the interface device 32 and optionally the cavity 16 are enclosed. Furthermore, the blockchain module 30a for hydrogen certification can be comprised by the device 1 (Figure 2a) or be present as an external entity (Figure 2b), wherein the device is configured to communicate with the blockchain module 30a. This applies analogously to a general hydrogen certification module 30. In the examples according to Figures 3a-d, the optically based measuring device 10 has essentially no physical contact with the sample 12, but has an optically transparent window 20 or an input window 20a and an output window 20b.For simplification and for illustrative purposes, Figures 3a-d are limited to the representation of possible measuring arrangements 10a, which essentially concern the measuring device 10 and the cavity 16. The examples according to Figures 3a-d relate in particular to a measuring arrangement 10a that enables the application of TDLAS.

[0144] According to Figure 3a, the window 20 is arranged on the cavity 16 in the form of the supply line 16b. The measuring device 10 emits light through the window 20 into a measuring section 10 within the supply line 16b, in particular by means of a tunable diode laser 28 (TDL). The light is reflected by the inner wall 16d opposite the window 20 (see Figure 3d) and guided through the window 20 back to a photodetector 10c or sensor of the measuring device 10. This measuring arrangement 10a particularly effectively enables continuous testing / measurement of continuously flowing sample gas 12, as described above.

[0145] In the measuring arrangement 10a according to Figure 3b, an input window 20a and an output window 20b are arranged opposite one another on the wall of a cavity 16 in the form of a storage tank 16a, so that light from a laser diode 10b can be detected via the input window 20a through the storage tank 16a and via the output window 20b by a photodetector 10c.

[0146] In the measuring arrangement 10a according to Figure 3c, the storage tank has a reflection wall 16d inside, so that only a single measuring window 20 is required. In this way, the reflection-based method according to Figure 3a or 3d can also be applied to a storage tank 16a.

[0147] Figure 3d further illustrates that the interface device 32 may comprise optical means for connecting the laser diode 10b and the photodetector 10c to the cavity 16 or to one of the windows 20, 20a, or 20b, respectively. Furthermore, the interface device according to Figure 3d comprises a heating element 34 for heating the wall 16c of the cavity 16.

[0148] Figure 4 illustrates the sensitivities achievable using TDLAS in the wavelength range relevant for a target substance. TDLAS can be performed very effectively with commercially available VCSL or DFB laser diodes in the near-infrared (NIR) range for target substances such as CH4, CO, CO2, H2S, and SO2. The gaseous target or non-target substances can be easily and selectively detected separately in the NIR range. To achieve even higher sensitivities, quantum cascade lasers (QCLs) can be used, for example, in the early mid-infrared (MIR) range.

[0149] Where applicable, all individual features presented in the exemplary embodiments can be combined and / or interchanged without departing from the scope of the invention. For example, the measuring arrangements 10a shown in Figures 3a-d can be used not only for the cavity 16, but also analogously for the measuring chamber 18 shown in Figures 2a and 2b. Furthermore, the specifications of the target substances, non-target substances, target groups, and non-target groups can be used equally in the proposed method and device. List of reference symbols:

[0150] 1 device

[0151] 10 Measuring device

[0152] 10a Measuring arrangement

[0153] 10b laser diode

[0154] 10c Photodetector / Sensor lOd Measuring section

[0155] 12 Hydrogen sample

[0156] 14 Evaluation unit

[0157] 16 cavity

[0158] 16a Hydrogen storage tank

[0159] 16b Hydrogen supply line

[0160] 16c wall

[0161] 16d interior wall

[0162] 18 Measuring chamber

[0163] 20 optically transparent windows

[0164] 20a Entrance window

[0165] 20b Exit window

[0166] 22 Protective enclosure

[0167] 22a Opening sensor

[0168] 24 Communication unit

[0169] 26 Recording device

[0170] 28 tunable laser diodes

[0171] 30 Hydrogen Certification Module

[0172] 30a Blockchain module

[0173] 32 Interface setup

[0174] 34 Heating element

[0175] 50 hydrogen sources / suppliers

[0176] 52 hydrogen consumers

[0177] 54 recipient groups

Claims

Patent claims 1. A method for identifying non-electrolysis hydrogen using target substances from target groups, comprising the steps: - defining (S14) a series of non-target groups, each non-target group comprising at least one non-target substance, the non-target substance being characteristic of a transport-related contamination of the sample (12), the transport-related contamination being in particular characteristic of the use of lubricants, plastic seals and / or external air for hydrogen transport; - Updating (S16) the target groups by subtracting the defined series of non-target groups from the previous target groups; - Providing (S20) a hydrogen sample (12); - checking (S30) whether the sample (12) contains a target substance, wherein the target substance is a substance from the following target groups: hydrocarbons, carbon-containing gases, sulphur-containing gases, volatile amines, formates or oxygenates; - Categorizing (S40) the sample (12) as non-electrolysis hydrogen if the sample (12) contains the target substance.

2. The method according to claim 1, comprising: - repeating (S31) the testing step (S30) n times for each further target substance in order to test the sample (12) for a series of n target substances, where n is greater than or equal to 2.

3. A method according to claim 1 or 2, comprising: - defining (S10) a reference pattern which specifies a proportion range of the target substance, and in particular a proportion range of the other target substances, in the sample; - optionally: linking (S12) the reference sample with at least one non-electrolysis hydrogen production process for which the reference sample is characteristic; and - optional: Repeat (S13) the steps Define (S10) and Link (S12) to create a series of linked reference patterns.

4. A method according to any one of the preceding claims, comprising: - determining (S32) a proportion of the target substance in the sample ( 12 ); - comparing (S34) the determined proportion with the proportion range of the reference sample; - Assigning (S36) the sample (12) to the at least one non-electrolysis hydrogen production process, provided that the determined proportion lies within the proportion range of the reference sample; - optional: Repeat (S37) the steps of matching (S34) and assigning (S36) for the series of linked reference patterns.

5. The method according to claim 3 or 4, wherein the proportion range of the target substance in the sample (12) is 0.001 to 100 ppmV, in particular 0.01 to 1 ppmV.

6. Method according to one of the preceding claims, wherein the providing (S20) of the sample (12) comprises: - continuous flow (S22) of sample gas past a measuring device (10); and wherein the testing (S30) comprises: - continuous measurement of the continuously flowing sample gas .

7. A method according to any one of the preceding claims, comprising: - Tracking (S50) categorized samples (12) by means of a hydrogen certification module (30), in particular by means of a blockchain module (30a) for hydrogen certification.

8. Method according to one of the preceding claims, wherein the target substance is one of the following substances: CH4, CO, CO2, H2S, SO2, methylamine, dimethylamine, trimethylamine or formaldehyde.

9. Method according to one of the preceding claims, wherein the step of checking (S30) whether the sample contains a target substance is carried out using absorption spectroscopy in the near or mid-infrared range, in particular diode laser absorption spectroscopy.

10. Device (1) for identifying non-electrolysis hydrogen by means of target substances from target groups, comprising - a measuring device (10) which is designed to detect the target substance in a hydrogen sample (12), - an evaluation unit (14) communicatively connected to the measuring device (10) which is designed to evaluate the sample (12) as non-electrolysis hydrogen if the target substance is detected in the sample (12) by means of the measuring device (10), wherein the target substance is a substance from the following target groups: hydrocarbons, carbon-containing gases, sulfur-containing gases, volatile amines, oxygenates or formates, wherein the evaluation unit (14) is designed to define a series of non-target groups, wherein each non-target group has at least one non-target substance, wherein the non-target substance is characteristic of a transport-related contamination of the sample (12), wherein the transport-related contamination is particularly characteristic of the use of lubricants, plastic seals and / or external air for hydrogen Transport; and to update the target groups by subtracting the defined set of non-target groups from the existing target groups.

11. Device according to claim 11, wherein the measuring device (10) is a measuring arrangement (10a) or a combination of several Measuring arrangements (10a) from the following list: infrared optical gas sensor, solid state gas sensor, Nernst sensor, catalytic converter sensor, gas chromatograph, quadrupole mass spectrometer, ion mobility spectrometer.

12. Device according to claim 11 or 12, comprising - a cavity (16) for storing or conveying hydrogen for a consumer (52), wherein the cavity (16) is designed in particular in the form of a hydrogen storage tank (16a) or a hydrogen supply line (16b), and - a measuring chamber (18) coupled to the measuring device (10) which can be fluidly connected to the cavity (16).

13. Device (1) according to claim 11 or 12, comprising - a cavity (16) for storing or conveying hydrogen for a consumer (52), wherein the cavity (16) is designed in particular in the form of a hydrogen storage tank (16a) or a hydrogen supply line (16b), and - an optically transparent window (20) which can be arranged on the cavity (16).

14. Device (1) according to one of claims 11 to 14, comprising a protective housing (22) in which the measuring device (10) and / or the evaluation unit (14) is / are accommodated, in particular wherein the protective housing (22) is sealed by means of a seal and / or is sealed by means of a lead seal.

15. Device (1) according to one of claims 11 to 15, comprising a communication device (14) which is communicative connected communication unit (24) which is set up for wireless or wired data communication.

16. Device (1) according to claim 15 or 16, wherein the protective housing (22) has an opening sensor (22a) for detecting an opening of the protective housing (22), in particular wherein the opening sensor (22a) is communicatively connected to the evaluation unit (14) and / or to the communication unit (24).

17. Device (1) according to one of claims 11 to 17, comprising - a recording device (26) communicatively connected to the measuring device (10) for logging and storing measurement data (10a) of the measuring device (10), in particular wherein the recording device (26) has a local, non-volatile data memory, and / or - a power supply device, in particular a secondary power supply device, which is designed to supply the device (1) with electrical energy and which is arranged in particular within the protective housing (22).

18. Device according to one of claims 11 to 18, wherein the measuring device (10) comprises a tunable laser diode (28).

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