Method and device for identifying non-electrolysis hydrogen
Patent Information
- Application Number
- AE202602834
- Authority / Receiving Office
- AE · AE
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-03-01
- Filing Date
- 2025-02-07
Smart Images
Figure ABST_ABST
Abstract
Description
Method and device for identifying non-electrolysis hydrogen The present invention relates to a method and an apparatus for identifying non-electrolysis hydrogen. Renewable or sustainable production of molecular hydrogen, H2, for industrial consumers or end consumers (referred to hereinafter as hydrogen production) is an essential component of the energy transition. In this context, it is customary to categorize hydrogen with a color coding according to the process for its production. For example, "gray hydrogen" is produced from fossil starting materials, for example by steam reforming from natural gas, with the carbon dioxide formed entering the Earth's atmosphere. "Blue hydrogen" is likewise of fossil origin, similarly to gray hydrogen, but is produced by steam reforming, except that the carbon dioxide formed is collected in the course of the production process, such that it does not enter the Earth's atmosphere. Turquoise hydrogen is produced by methane pyrolysis, resulting in solid carbon which – similarly to blue hydrogen – is processed further in such a way that no carbon dioxide enters the Earth's atmosphere. Green hydrogen is produced using exclusively renewable or sustainably produced energies and water by means of an electrolysis process and thus relates to a particularly sustainable form of hydrogen production. The hydrogen is thus electrolysis hydrogen. It is known that the source of hydrogen atoms can be distinguished by an isotope method by fossil or non-fossil origin. This is based on the concept that the isotope ratios, on account of isotope fractionation processes over the course of fossil storage for long periods, differ from the isotope ratio of surface water which is typically used for electrolysis. It is thus possible in principle to distinguish, for example, electrolysis hydrogen from blue hydrogen. However, isotope detection is very complex and costly from a metrological point of view. WO 2023 / 105261 A1 describes a method and a system comprising the taking of a sample of hydrogen gas, analyzing the chemical composition for impurities such as CO, N2, CH4 and deuterium, and using specific logic to certify the origin of the hydrogen gas, in particular assisted by blockchain technology. At present, there are no known methods or apparatuses for identifying non-electrolysis hydrogen or hydrogen of fossil origin which is supplied to a consumer on a large or industrial scale. Summary of the invention Proceeding from 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. This object is achieved by a process having the features of claim 1. Advantageous developments will be apparent from the dependent claims, the description and the figures. Accordingly a method of identifying non-electrolysis hydrogen by means of target substances from target groups is proposed, comprising the steps of: - defining a series of non-target groups, wherein each non-target group includes 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 characteristic in particular of a use of lubricants, plastic seals and / or extrinsic air for hydrogen transport; - updating the target groups by subtracting the defined series of non-target groups from the previous target groups; - providing a hydrogen sample; - checking whether the sample includes a target substance, where the target substance is a substance from the following target groups: hydrocarbons, carbon-containing gases, sulfur-containing gases, volatile amines, formates or oxygenates; - categorizing the sample as non-electrolysis hydrogen when the sample includes the target substance. What is meant in the present context by non-electrolysis hydrogen is a substance mixture which is commercially traded as molecular hydrogen, i.e. H2, and which is typically not classified as electrolysis hydrogen according to the examples and definitions mentioned above. Thus, "non-electrolysis hydrogen" includes all mixtures consisting essentially of hydrogen and produced from coal, natural gas or biomass. The step of "providing a hydrogen sample" can be effected, for example, in that the sample is taken from a hydrogen supply provided for a consumer. Furthermore, the sample can also remain within the hydrogen supply provided for a consumer, i.e. not be taken, and be provided in that optical or physical access to the sample situated within the hydrogen supply is provided. For example, optical access can be provided by means of a window at a measurement chamber or at a hydrogen feed conduit. Physical access can be provided via positioning of a sensor within the measurement chamber or the hydrogen feed conduit, such that the sensor is physically in contact with the sample. The step of "checking whether the sample includes a target substance" can be implemented by means of a measuring device set up to detect the target substance in the sample. Because the target substance to be detected in the sample comes from one of the abovementioned target groups, it is particularly easy to deduce a non-electrolysis production method, as explained hereinafter. Although electrolysis hydrogen may contain water, H2O, in the context of a "wet electrolysis", or may contain oxygen, O2, owing to entrainment of anode gases, it typically does not include any substance from the abovementioned target groups. In the context of the present invention, it has been recognized that non-electrolysis-hydrogen production processes cause characteristic accompanying products in the hydrogen. A study was then conducted as to which accompanying products are present in non-electrolysis-hydrogen preparation processes aside from hydrogen, the main product. The target groups mentioned were derived from this study. It has been recognized here that each non-electrolysis hydrogen production process characteristically has certain accompanying products that remain in detectable amounts in the product even in spite of hydrogen purification. This can be attributed to a further finding, namely that purification for removal of the accompanying products on an industrial scale is incomplete, as illustrated by the example that follows. For example, the purification of hydrogen for certain industries or applications may be controlled by standards. For example, standard ISO 14687-3 allows comparatively high tolerances for accompanying products in hydrogen for fuel cells in the stationary sector. Furthermore, ISO 14687-2, by contrast, envisages only limited maximum proportions of accompanying products in the hydrogen for PEM fuel cells in the automotive sector. In the context of the present invention, it has been recognized that conventional purification processes are designed to meet such or more comparable standards and specifications, such that the purifications typically do not give 100% pure H2. The target groups are specified further hereinafter on the basis of examples. The target group "hydrocarbons" especially comprises pure carbon-hydrogen compounds such as methane that has not been converted, for example, in a natural gas steam reforming operation or in a methane pyrolysis operation. In the present context, "pure carbon-hydrogen compounds" mean especially elemental hydrocarbons, i.e. compounds consisting solely of carbon and hydrogen, for example alkanes and alkenes. The target group "hydrocarbons" thus includes, for example, ethane, propane, butane and pentanes. The target group "carbon-containing gases" includes in particular carbon oxides, i.e. oxocarbons, for example carbon monoxide or carbon dioxide. In other words, the target group "carbon-containing gases" may include oxocarbons, i.e. compounds formed exclusively from carbon and oxygen. In the case of steam reforming, a typical combined proportion of CO + CO2 after a purification of the hydrogen is about 10 ppmv. The target group "sulfur-containing gases" includes in particular hydrogen sulfide and sulfur dioxide. Sulfur-containing substances may be present in natural gas or coal, such that sulfur-containing gases may firstly be indicative of a fossil, i.e. a non-electrolysis, hydrogen source. Secondly, sulfur-containing gases may be indicative of methane produced from biomass in order to be processed to hydrogen by methane reforming or methane pyrolysis. Hydrogen produced from biomass is likewise a non-electrolysis hydrogen and is sometimes referred to as orange hydrogen. The target group "volatile amines" includes amines which typically give off a fishy odor and are attributable to an amine scrubbing for controlled removal of carbon dioxide or hydrogen sulfide, for example methylamine, dimethylamine, trimethylamine. Amine scrubbing is typical of non-electrolysis hydrogen production processes in which the hydrogen atoms originate from coal, fossil methane or biomass methane. The target group "oxygenates" includes, for example, formaldehyde, acetaldehyde and the esters of formic acid. In the context of the present invention, it has been recognized that formaldehyde and / or formates in the case of methane production from biomass may be present as an accompanying product in non-electrolysis hydrogen. As described above, what is examined is whether the sample includes a target substance, where the target substance is a substance from said target groups. What is meant in the present context by a "substance" is a material or a chemical compound. Therefore, the checking may be provided for a single target substance. Furthermore, the checking may be provided for a number of target substances that come from one of the target groups or from a plurality of the target groups. For example, the checking may be provided solely for methane or solely for sulfur-containing gases. In this way, the checking can be simple and rapid, since the presence of methane or the presence of a sulfur-containing gas, according to the above insights, suggests that the sample originates from non-electrolysis hydrogen. In a further example, the checking may be provided for CO2 and for a volatile amine. This example tests for two potentially supplementary target groups: For example, if it was not possible to detect any CO2 in the sample, this could be attributable to thorough amine scrubbing of a hydrogen produced from fossil sources, and so this may be followed by additional checking for a volatile amine. Analogously, in a further example, the checking may be provided for hydrogen sulfide and for a volatile amine. In other words, the checking may relate to any combination of the target substances or substances from the target groups, where a combined check can be carried out in parallel, i.e. essentially simultaneously, or sequentially, i.e. downstream for example. The step of "categorizing the sample as non-electrolysis hydrogen when the sample includes the target substance" can be effected, for example in that a data set corresponding to the sample or to the hydrogen supply checked is given the attribute "non-electrolysis" or "positive", where "positive" marks the detection of one of the accompanying products described above. Furthermore, the method may comprise the following step: - n-fold repetition of the step of checking for a further target substance in each case in order to test the sample for a series of n target substances, where n is not less than 2. By way of example, the sample can be checked in a first checking step for a plurality of target substances in parallel, for example CO and CO2, and in a subsequent second checking step it is possible in turn to check in parallel for a plurality of target substances, for example, for H2S and SO2 volatile amines, and in a subsequent third checking step to check for volatile amines. In the case of sequential checking, the sample checked may be the same each time. Additionally or alternatively, a new hydrogen sample may be provided for each of the sequential checks. Furthermore, a combination of the above-described procedure can be implemented, for example in that the first and second checking steps are effected for a first sample provided and the third checking step is effected for a second sample provided. It may further be the case that an intended triple repetition of the step of checking in the case of a positive sample is terminated after the first or second testing step and the sample is immediately categorized as non-electrolysis hydrogen. Owing to the procedures described above, the method can be designed and adapted in a particularly simple manner for a specific set of target groups or target substances and for a sensor arrangement to be designed for performing of the checking steps. Furthermore, the method may comprise the following steps: - defining a reference pattern that specifies a range of proportions of the target substance, and in particular a range of proportions of the further target substances, in the sample; and - associating the reference pattern with at least one non-electrolysis hydrogen production method for which the reference pattern is characteristic. In the above step of "defining a reference pattern", the reference pattern may specify the range of proportions of a single target substance in the sample. Additionally or alternatively, the reference pattern may specify the range of proportions of a plurality of target substances in the sample. The latter is the case in particular if the step of "checking" is to be repeated for further, i.e. a plurality of, target substances. In any case, the reference pattern should be defined by means of the choice of target substances and respective ranges of proportions such that the reference pattern according to the insights described above is characteristic of a non-electrolysis hydrogen production method, i.e. of a particular form of non-electrolysis hydrogen. In the subsequent abovementioned step of "associating", the reference pattern is associated with at least one non-electrolysis hydrogen production method for which the reference pattern is characteristic. In this way, when the sample tests positive, i.e. when the sample includes one or more target substances, it is possible to deduce one or more possible non-electrolysis production methods. Following on from one of the above examples, in the case of steam reforming, a typical combined proportion of CO and CO2 after purification of the hydrogen may be about 10 ppmv. Accordingly, for example, a reference pattern that may be associated with the fossil-based production method of "steam reforming" specifies a range of proportions of the target substance CO of 0.01 to 10 ppmv and a range of proportions of the target substance CO2 of 0.01 to 10 ppmv in the same sample. The unit ppmv relates to the mixing ratio parts per million by volume. For example, 8 ppmv CO in hydrogen means the same as 8 microliters of CO per liter of hydrogen. As an alternative to ppmv, for example, µg / g (micrograms per gram) may be used to indicate a proportion or concentration of an accompanying product in hydrogen. In addition, for example, the non-electrolysis hydrogen production processes "methane from biomass", for example via reforming by means of supercritical water or via pyrolysis, can be associated with a reference pattern that specifies a range of proportions of the formaldehyde target substance of 0.001 to 100 ppmv, especially of 0.01 to 10 ppmv. In addition, a plurality of reference patterns may be combined and this combination may be associated with a specific non-electrolysis hydrogen production process. In addition, the method may comprise the following step: - repeating the above steps of "defining" and "associating" in order to create a series of associated reference patterns. Furthermore, the method may comprise the following steps: - ascertaining a proportion of the target substance in the sample; - matching the proportion ascertained with the range of proportions of the reference pattern; and - assigning the sample to the at least one non-electrolysis hydrogen production method, provided that the determined proportion lies within the range of proportions of the reference pattern. In addition, the method may comprise the following step: repeating the above steps of "matching" and "assigning" for the series of associated reference patterns. In other words, the "ascertaining of a proportion of the target substance in the sample" relates to the ascertaining of 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. Owing to the procedure described above, a multitude of relevant non-electrolysis hydrogen production methods can each be associated with reference patterns, such that one or more possible non-electrolysis hydrogen types can be deduced particularly easily via ascertaining, matching and assigning. In one development, the range of proportions of the target substance in the sample may be 0.001 to 100 ppmv, in particular 0.01 to 1 ppmv. In particular, the range of proportions, as described above, can be determined from the expected concentrations of one of the accompanying products characteristic of a non-electrolysis hydrogen production process. In this way, a specific range of proportions can be defined for a reference pattern for every target substance, i.e. for every accompanying product. By way of example, a particular target substance may be specified in different reference patterns with different ranges of proportions in each case. In this way, the reference patterns can be matched individually to respective non-electrolysis hydrogen production processes. In addition, the step "providing a hydrogen sample" may comprise: - continuous flow of sample gas past a measuring device. In addition, the step of "checking" may comprise: - constantly analyzing the sample gas flowing continuously past. In other words, the sample can be passed through the measuring device in a continuous hydrogen gas stream while the gas stream is being constantly analyzed, and therefore it is being tested whether the sample in the form of the gas stream includes the target substance. What is meant in the present context by constantly analyzing is that measurements or measurement events can be collected continuously or discretely without having to actively adjust the measurement arrangement of measuring device and sample. For example, the taking of a sample from a hydrogen tube or storage tank and feeding of the sample into a separate measurement chamber constitutes an active adaptation in the above sense and typically does not enable constant analyzing in the above sense. Owing to the procedure described above, the checking of the sample may be constant and thus can be used in particular in the case of hydrogen deliveries that are supplied continuously to a consumer by pipeline. Furthermore, the method may comprise the following step: - tracking categorized samples by means of a hydrogen certification module, in particular by means of a blockchain module for hydrogen certification. In other words, the step of "categorizing the sample" may be a categorized measurement event which, for the purpose of hydrogen certification, is sent to a data memory of a hydrogen certification module or of a blockchain module for hydrogen certification. This can be done in particular by associating the categorized measurement event with the hydrogen delivery sampled. Thus, the categorized measurement event is permanently safeguarded and invariably associated with the hydrogen delivery sampled. In this way, the categorizing of the sample or the result thereof is transparent and comprehensible to further groups of recipients, for example the hydrogen supplier, the hydrogen consumer, authorities and / or certification bodies. It may also be the case that the target substance is one of the following substances: CH4, CO, CO2, H2S, SO2, methylamine, dimethylamine, trimethylamine or formaldehyde. Furthermore, the step "checking whether the sample includes a target substance" can be effected using an absorption spectroscopic method in the near infrared (NIR) or mid infrared (MIR), in particular by diode laser absorption spectroscopy, which is also referred to as tunable diode laser absorption spectroscopy, referred to hereinafter as "TDLAS" for short. These methods are particularly suitable for detecting a plurality of gases selectively, i.e. without mutual influencing of the test result, and precisely with regard to the quantification of the gas concentration. The object stated above is also achieved by an apparatus having the features of claim 9. Advantageous developments of the method will be apparent from the present description and the figures. Accordingly, an apparatus for identifying non-electrolysis hydrogen by means of target substances from target groups is proposed, comprising - a measuring device set up to detect a target substance in a hydrogen sample, - an evaluation unit communicatively connected to the measuring device and set up to categorize the sample as non-electrolysis hydrogen when 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 includes 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 characteristic in particular of a use of lubricants, plastic seals and / or extrinsic air for hydrogen transport; and updating the target groups by subtracting the defined series of non-target groups from the previous target groups. The insights, technical effects and advantages elucidated above with respect to the proposed method are equally correspondingly applicable to the proposed apparatus. This relates in particular to the specification of the target substances and the target groups. Furthermore, the measuring device can include a measurement assembly or a combination of a plurality of measurement assemblies from the following list: infrared gas sensor, solid-state gas sensor, Nernst sensor, exothermicity sensor, gas chromatograph, quadrupole mass spectrometer, ion mobility spectrometer. Furthermore, the apparatus may comprise: - a cavity for storing or conveying hydrogen for a consumer, wherein the cavity is in particular in the form of a hydrogen storage tank or a hydrogen feed conduit, and - a measurement chamber which is coupled to the measuring device and is fluidically connectable to the cavity. What is meant in the present context by a cavity is a volume or space in which a measurement on a sample can be undertaken. This includes a pipeline, in which case the sample at the moment of measurement may be in an intended section, volume or space of the pipeline. What is meant in the present context by the measurement chamber is a space in which the sample can be provided, such that the sample can be tested by means of the measuring device. The measurement chamber may, for example, be a non-enclosed space within the cavity for storing or conveying hydrogen. Additionally or alternatively, the measurement chamber may be a space separate from the cavity, i.e. a separate measurement chamber outside the cavity. The measuring device may be coupled to the measurement chamber in that the measuring device has sensors, for example, on or within the measuring chamber. Furthermore, the measuring device may be coupled to the measurement chamber in that radiation emanating from or received by the measuring device passes through the measurement chamber. The fact that the measurement chamber is fluidically connectable to the cavity includes both arrangements in which the measurement chamber is by design arranged within the cavity and fluidically connected, and arrangements in which the measurement chamber is temporarily connected to the cavity via a temporary connecting conduit for the purpose of providing the sample. Furthermore, this relates to arrangements in which the sample is removed from the cavity by means of a separate transport vessel and fed to the measurement chamber, wherein a fluidic connection between the cavity and the transport vessel is separated before the transport vessel is fluidically connected to the measurement chamber. Additionally or alternatively, the apparatus may comprise an optically transparent window which is positionable on the cavity. What is meant in particular by the abovementioned hydrogen feed conduit is a pipeline by which a hydrogen supply is to be supplied to any desired consumer. The consumer may be a person or a technical unit that is to source electrolysis hydrogen from a hydrogen supplier. Because the optically transparent window is positionable, i.e. can be positioned, on the hydrogen feed conduit, for example, the above-described constant measuring of the sample gas continuously flowing past is possible, in particular using an infrared measuring device. It is thus possible to dispense with positioning of a sensor within the hydrogen feed conduit, as a result of which the sensor could possibly be contaminated. Furthermore, the optically transparent window may be positionable on the hydrogen storage tank, and so an infrared measuring device can be used in this case too. In this way, it is possible, for example, to dispense with sampling or provision of a separate measurement chamber. Alternatively, the cavity may not be encompassed by the apparatus. In general, and in this case in particular, the apparatus have an interface device for coupling of the measuring device to the cavity. The interface device may comprise the optically transparent window and / or a device for gas sampling. Furthermore, the apparatus may comprise a protective housing that accommodates the measuring device and / or the evaluation unit. The protective housing may be sealed by a seal. Additionally or alternatively, the protective housing may be sealed by a security seal. Furthermore, the apparatus, in particular the whole apparatus, may be enclosed by the protective housing. Owing to the protective housing, the risk of unwanted or even deliberate manipulation of the measuring device, of the evaluation unit or of the whole apparatus can be mitigated. By means of a seal or security seal, it is possible to prove that unwanted manipulation has been attempted. Furthermore, the apparatus may include a communication unit which is communicatively connected to the evaluation unit and which is set up for wireless or wired data communication. In particular, the evaluation unit may be set up to store a series of measurement events in a measurement protocol. The communication unit may be set up to communicate individual measurement events or the measurement protocol to external recipients. Such an external recipient may be the abovementioned hydrogen certification module or blockchain module or a receiving module for one of the abovementioned groups of recipients. The result of the categorizing of the sample can thus be communicated to external recipients or the groups of recipients. In this way, the non-electrolysis hydrogen can be identified and detected in a transparent and comprehensible manner and thus particularly robustly. In one development, the protective housing can have an opening sensor for detecting an opening of the protective housing. Furthermore, the opening sensor can be communicatively connected to the evaluation unit and / or to the communication unit. In this way, an unwanted manipulation attempt can be detected instantaneously. Furthermore, a detected manipulation attempt can thus be logged or communicated to the groups of recipients. Furthermore, the apparatus may have a recording unit communicatively connected to the measuring device for logging and storing measurement data from the measuring device. In particular, the recording unit may have a local, non-volatile data memory. Furthermore, the recording unit may be provided in a separate protective housing which protects the recording unit from fire, vibration, water and electric shock, for example. In other words, the recording unit can be provided analogously to a flight recorder. The recording unit may also be set up to log and store the above-described manipulation attempts, i.e. may be coupled to the opening sensor. Owing to the recording unit, measurement data can be retained in a robust and secure manner even in the event of technical faults or manipulations. Furthermore, the apparatus may have an energy supply device which is set up to supply the apparatus with electrical energy. The energy supply device may take the form of a primary main energy supply device or may take the form of a secondary energy supply device which, in the event of a failure of an external main energy supply device, supplies the apparatus with electrical energy in an alternative manner, for example in the manner of an emergency generator. In particular, the energy supply device may be positioned within the protective housing. In this way, the apparatus can be provided as an autonomous unit, which is also particularly secure with respect to manipulation. Furthermore, the measuring device may include a tunable laser diode, i.e. a tunable diode laser (TDL for short). In particular, the measuring device may be set up to employ the TDLAS mentioned further up. Brief description of the figures Preferred further embodiments of the invention are elucidated in detail by the description of the figures that follows. These show, in schematic form: Figure 1a method of identifying non-electrolysis hydrogen in a working example; Figures 2a,bin each case a working example of an apparatus for identifying non-electrolysis hydrogen; and Figures 3-ddetails of further examples of an apparatus for identifying non-electrolysis hydrogen; and Figure 4sensitivities for relevant target substances that are achievable by TDLAS. Detailed description of working examples Working examples are described hereinafter with reference to the figures. Identical, similar or equivalent elements in the different figures are given identical reference numerals, and repeated description of these elements is dispensed with to some extent in order to avoid redundancy. Figure 1 shows a method of identifying non-electrolysis hydrogen. More specifically, figure 1 shows various possible configurations of the method. A step S10 involves defining a reference pattern that specifies a range of proportions of a target substance, and in particular a range of proportions of further target substances, in the sample. The target substance or the further 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 may be one of the following substances: CH4, CO, CO2, H2S, SO2, methylamine, dimethylamine, trimethylamine or formaldehyde. After step S10, step S12 or even step S20 can optionally be conducted. Step S12 involves associating the reference pattern with at least one non-electrolysis hydrogen production method for which the reference pattern is characteristic. In the context of the present invention, various non-electrolysis hydrogen production processes were examined for typical accompanying products. This study was used to infer the abovementioned target groups or target substances that correspond to the typical accompanying products of non-electrolysis hydrogen. As elucidated further up, what is called green hydrogen is produced by electrolysis. This involves electrolytic cleavage of water by redox reactions at the anode and cathode: Cathode: 2 H2O + 2e- -> H2 + 2 OH-Anode: 4 OH- -> 2 H2O + O2+ 4 e-Electrons are released at the cathode and are taken up again by the anode. In the overall reaction, water thus forms virtually exclusively molecular hydrogen, H2, and molecular oxygen, O2, according to the overall reaction: 2 H2O -> 2 H2 + O2. The electrolysis is effected with demineralized water of high purity, such that, aside from the main H2 product, only H2O (in the case of wet electrolysis) and small amounts of O2 owing to entrainment of anode gases are to be expected. This applies to alkaline electrolysis, polymer electrolyte membrane electrolysis (PEM), and also to high-temperature electrolysis. It is thus to be expected that green hydrogen (apart from water and oxygen) will not include any accompanying products, especially any substances from the target groups or any of the target substances. In addition, in the context of the present invention, the non-electrolysis hydrogen preparation processes described below were examined. For example, hydrogen can be produced by steam reforming from fossil methane, for example natural gas. Methane is broken down here by supplied heat (endothermic process) and water to CO and H2 according to the following equation: CH4(g) + H2O(g) <-> CO(g) + 3 H2(g) The required enthalpy of reaction can also be applied by the partial oxidation; this process is exothermic: 2 CH4(g) + O2(g) <-> 2 CO(g) + 4 H2(g) The hydrogen yield can be increased by converting the carbon monoxide formed to 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 from 0.6% to 1.5% by volume, depending on the mode of operation of the water-gas shift reactor. Thus, small proportions of CO and unconverted CO2 are still present as accompanying products in what is called gray hydrogen, i.e. non-electrolysis hydrogen. Furthermore, it can be inferred from the above reaction equations that the gray hydrogen may contain unconverted CH4. Furthermore, it is possible to subject gray hydrogen to an amine scrub in order to scrub out the unconverted CO2 as completely as possible. In the context of the present invention, it has been recognized that the gray hydrogen still includes about 10 ppmv CO + CO2 even after an amine scrub. Furthermore, the invention, in the definition of the target groups or target substances, exploits the fact that, in general, the non-electrolysis hydrogen purified by amine scrubbing still includes traces of volatile amines. Furthermore, it has been recognized that fossil methane contains sulfur-containing constituents, the H2S and SOx derivatives of which are detectable in small amounts in the non-electrolysis hydrogen even after purification. In addition, non-electrolysis hydrogen can be produced, for example, from methane which is obtained from biomass. Such biomass may relate, for example, to solids such as wood, sewage sludge or municipal wastes that cannot be evaporated, and so the reforming here is effected under different conditions than in the case of methane from natural gas. For example, in the case of biomass, the reforming can be effected by means of supercritical water over a heterogeneous catalyst at 250–300 bar and 400–550°C with a large excess of water. The accompanying products in hydrogen to be expected here are firstly those mentioned in the case of fossil methane reforming. Furthermore, a wide range of simple hydrocarbons and oxygenates, including formaldehyde and formates, is to be expected because of the thermal cleavage of the biomass. Accordingly, these further accompanying products can be taken into account for the definition of the target groups or target substances. In addition, non-electrolysis hydrogen can be produced, for example, by methane pyrolysis, in particular thermally or by the Kværner process. This in turn relates firstly to fossil methane and secondly to methane from biomass. In thermal methane pyrolysis, the methane gas can be supplied with thermal energy, for example in that the methane gas is introduced at the base of an upright bubble column reactor and rises as bubbles in liquid metal within the reactor. The pyrolysis proceeds during the rising of the bubbles. When the bubbles arrive at the top end of the liquid metal reactor, they burst open and release a mixture of hydrogen, (solid) carbon and residual methane. This is followed by removal of the residual methane or purification of the hydrogen. The main reaction equations of the Kværner process or of the bubble column reactor describe the formation of hydrogen and carbon, which are present as main fractions in the product:Reaction equation: CH4 -> C + 2 H2In the general case: CnHm + energy -> n C + ½m H2 In the context of the present invention, however, it has been recognized that, owing to the use of natural gas as reactant, sulfur-containing gases, especially H2S and SOx, are to be expected in the product stream, and also that unconverted CH4, further hydrocarbons and H2O are typically present in the product stream. Furthermore, it has been recognized that the removal of or purification of these substances does not proceed to an extent of 100%, and so they are to be expected as accompanying products in this type of non-electrolysis hydrogen. Accordingly, these aforementioned accompanying products can be taken into account for the definition of the target groups or target substances. Again with regard to figure 1, a step S14 is effected, comprising defining S14 a series of non-target groups, where each non-target group includes at least one non-target substance, where the non-target substance is characteristic of transport-related contamination of the sample. The transport-related contamination may be characteristic of the use of lubricants, plastic seals and / or extrinsic air for hydrogen transport. Step S14, in terms of time of logic, may be performed before, after or in parallel to step S12. Regardless of this, in a step S13, the steps of defining S10 and associating S12 can be repeated in order to generate a series of associated reference patterns. For example, a first reference pattern may be directed to the identification of produced by coal gasification, a second reference pattern to the identification of blue hydrogen, and a third reference pattern to the identification of turquoise hydrogen (Kværner method). Furthermore, individual non-target substances may be identified and non-target groups may be inferred therefrom. Additionally or alternatively, non-target groups may be identified and specific non-target substances derived therefrom. Step S14 is based on the finding that even electrolysis hydrogen may have impurities on account of transport-related phenomena that could lead to a false-positive test result, i.e. to an unjustified categorization as "non-electrolysis" if these phenomena were not taken into account. The method can thus be made even more robust by means of step S14. For example, the following impurities may arise on the transport chain for hydrogen: traces of hydrocarbons (short- to long-chain hydrocarbons) that can be introduced into the hydrogen to be transported by lubricants (e.g. in the course of compression) and plastic seals. Significant air constituents N2, O2 or else moisture, which can be introduced into the hydrogen to be transported through use of previously unventilated pipes, pumps or leaks. For example, step S14 may comprise a calibration in that, in a test, high-purity hydrogen is supplied to the consumer by means of a specific transport chain, with detection and analysis of all the accompanying products and impurities, for example by means of high-resolution laboratory equipment. Furthermore, it may be the case that permitted ranges of proportions for the identified non-target substances are ascertained. For example, it might be possible to identify silicone oils as one of the non-target groups, and permitted ranges of proportions may be defined in each case for particular silicone oils. Furthermore, particular long-chain hydrocarbons, which may typically originate from lubricating oils, might be identified as one of the non-target groups and, for particular lubricating oils, permitted ranges of proportions may be defined in each case for particular long-chain hydrocarbons. After step S14, the target groups are updated in a step S16 by subtracting the defined series of non-target groups from the previous target groups. The previous target groups mean those from step S10 or S12. In addition, step S16 may comprise subtracting the defined series of non-target substances from the previous target substances. 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 ranges of proportions of non-targets newly identified in step S14 can be quantitatively subtracted from the previously defined ranges of proportions (of the targets). For example, a lubricating oil used in the transport chain could contain sulfur, for example a lubricating oil for lubricating a pump. In that case, by means of the proposed calibration, it may be recognized that extremely small amounts, for example less than 0.5 ppmv, of sulfur-containing gases are present in the electrolysis hydrogen - exclusively for transport reasons. In step S16, a previously defined range of proportions of 0.1 to 100 ppmv for sulfur-containing gases can then be updated to 0.5 to 100 ppmv. After step S10, optionally after step S12, S13 or S16, in a step S20, a hydrogen sample 12 is provided S20 for a measuring device 10. With regard to the reference numerals for the apparatus components, reference is made to figures 2a,b and 3a-d. The hydrogen provided for the consumer 52 is supplied by a hydrogen source 50 or hydrogen supplier 50 (see figures 2a,b, 3a). The delivery is effected by means of a cavity 16 for storing or conveying hydrogen for the consumer 52, where the cavity 16 is in the form of a hydrogen storage tank 16a (see figures 2b, 3b,c) or a hydrogen feed conduit 16b (see figures 2a, 3a,d). The providing S20 of the sample 12 can be effected, for example, in that the sample 12 is taken from the hydrogen feed conduit 16b and supplied to a separate measurement chamber 18 (see figure 2a), or in that the sample 12 is taken from the hydrogen storage tank 16a and supplied to the measurement chamber 18 (see figure 2b). Furthermore, the providing S20 can be effected 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, where the measuring device performs a checking S30 or measuring operation in a measurement 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), may be positioned at the cavity 16, through which the measuring device performs the checking / measuring operation in the measurement section 10d within the cavity 16. Alternatively, the providing S20 can be effected in that the measuring device 10 has a sensor, positioned within the cavity, for checking / measuring of the sample 12. After the sample 12 has been provided S20, the sample is checked in a step S30. More specifically, in the simplest variant, the checking ascertains whether the sample 12 includes any of the target substances or any substance from the target groups. Furthermore, the checking S30 may comprise a more accurate measurement, in particular a step S32 of ascertaining a proportion of the target substance in the sample 12. Optionally, steps S30 and / or S32 can be repeated in a step S31. In this way, the sample 12 can be examined for a plurality of target substances. If this is to be done sequentially, this can of course be done by another providing S20 of a fresh sample, without this being illustrated explicitly in figure 1. Step S32 of ascertaining is followed by a step S34 of matching (S34) of the ascertained proportion with the range of proportions of the reference pattern and by a step S36 of assigning the sample to the at least one non-electrolysis hydrogen production method if the ascertained proportion lies within the range of proportions of the reference pattern. Optionally, steps S34 and S36 can be repeated in a step S37 before the downstream step S40. The matching S34 and assigning S36 can thus be effected correspondingly for the plurality of samples checked or analyzed. Steps S32 to S37 can be performed using further components of the proposed apparatus 1, in particular an evaluation unit 14 which is communicatively connected to the measuring device 10 (see figures 2a,b) and which can be set up to perform step S40 and / or steps S32 to S36. After step S30 or after step S36, in a step S40, the sample 12 is categorized as non-electrolysis hydrogen if the sample 12 includes the target substance. In the simplest case, the categorizing can be effected merely in that a data set corresponding to the sample 12 or to the tested hydrogen delivery is given the attribute "non-electrolysis" or "positive", where "positive" indicates detection of one of the accompanying products described above. Furthermore, for example if steps S32 to S36 have been performed, the categorizing S40 may comprise storing further attributes in the form of the ascertained proportion according to S32, the result of the matching with the reference pattern according to S34, or the assigned production method according to S36 in the data set corresponding to the hydrogen delivery checked. Step S40 may be followed by a step S50 of tracking categorized samples 12 by means of a hydrogen certification module 30, in particular by means of a blockchain module 30a for hydrogen certification (see figures 2a,b). In particular, the measurement event described further up may be associated with the aforementioned attributes, with tracking of the resulting data record by means of the module 30 or 30a. Figures 2a,b each show a working example of an apparatus 1 for identifying non-electrolysis hydrogen, wherein the hydrogen according to figure 2a is supplied to the consumer 52 by means of the above-described feed conduit 16b and the hydrogen according to figure 2a is supplied to the consumer 52 by means of the above-described storage tank 16a. In principle, the apparatuses 1 of figures 2a to 3d are set up to implement the method proposed. Accordingly, the above description of figure 1 is applicable to the examples according to figures 2a to 3d. In order to avoid repetitions, the features addressed in particular hereinafter are those that have not been discussed or barely addressed. This is likewise applicable to figures 3a-d, which show details of further examples of an apparatus 1 for identifying non-electrolysis hydrogen. The apparatuses 1 according to figures 2a to 3d in particular have the following in common: The apparatus 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, a protective housing 22 accommodating the measuring device 10 and / or the evaluation unit 14, and the communication unit 24. 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 apparatus 1 comprises a recording unit 26, communicatively connected to the measuring device 10, for logging and storing measurement data from the measuring device 10, and an energy supply device (not shown in the figures) which is configured to supply the apparatus 1 with electrical energy, where the energy supply device is within the protective housing 22. According to figures 2a,b, the providing S20 is effected by sampling by means of an interface device 32. In the case of the feed pipe 16b, the interface device 32 may be positioned permanently, for example in a fixed manner, on the cavity 16 in the form of the feed pipe 16b. In the case of the storage tank 16a, the interface device 32 may be positioned detachably on the cavity 16 in the form of the storage tank 16a. After sampling, the sample 12 may relate, for example, to an amount of 100-5000 mlN (N = standard conditions) of hydrogen, which possibly includes the accompanying products described above. The apparatus 1 according to figures 2a,b comprises a measurement chamber 18 that includes the measuring device 10. The evaluation unit 24 may comprise a control unit (not shown) or be coupled to a control unit, where the evaluation unit 24 or the control unit controls the controlling of the apparatus 1, in particular the physical sampling and the data processing. Within the measurement chamber 18 is a selective gas detector which is encompassed by the measuring device 10 and which measures the proportion or the concentration of the abovementioned target substances and / or non-target substances (for example transport chain-related impurities). Before the performance of a further test / measurement in the measurement chamber, the sample 12 may be released to the environment, sent to a utilization or returned to the cavity 16, in particular the feed conduit 16b. For this purpose, the apparatus 1, in particular the interface unit 32, may have corresponding gas conduits and a pump unit (not shown). Furthermore, the interface unit 32 may be set up to expand the sample 12 from the comparatively high delivery pressure. In particular, the expansion can be effected to a pressure slightly above the atmospheric level, because this avoids potential penetration of ambient air into the measurement chamber 18 and hence measurement errors. Furthermore, the apparatus 1, in particular the interface unit 32, may have means of heating said gas conduits and the measurement chamber 18. In this way, it is possible to prevent condensation of somewhat heavier volatile constituents on the walls of the interface unit 32 and of the measurement chamber 18. Owing to the arrangement according to figure 2b, the checking S30 and categorizing S40 can be effected in particular before the hydrogen supply stored in the tank 16a is directed to the consumer, for example by coupling of connecting pieces 16c. In figures 2a,b, the apparatus 1 is shown schematically as a dashed box in order to make clear which components are encompassed by the apparatus 1. For example, the protective housing 22 may be sealed or security-sealed and may have such an extent that the interface apparatus 32 and further optionally the cavity 16 is accommodated. Furthermore, the blockchain module 30a for hydrogen certification may be encompassed by the apparatus 1 (figure 2a) or be present as an external entity (figure 2b), where the apparatus is configured for communication with the blockchain module 30a. This is analogously applicable to a general hydrogen certification module 30. In the examples according to figures 3a-d, the optics-based measuring device 10 has essentially no physical contact with the sample 12, but rather has an optically transparent window 20 or an input window 20a and an output window 20b. For simplification and for reasons of illustration, figures 3a-d are restricted to the illustration of possible measurement arrangements 10a, which relate essentially to the measuring device 10 and the cavity 16. The examples according to figures 3a-d relate in particular to a measurement arrangement 10a that enables the employing of TDLAS. According to figure 3a, the window 20 is positioned on the cavity 16 in the form of the feed conduit 16b. The measuring device 10 emits light, in particular by means of a tunable laser diode 28, TDL, through the window 20 into a measurement section 10 within the feed conduit 16b. The light is reflected at 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 measurement assembly 10a particularly effectively enables continuous checking / measuring of sample gas 12 flowing continuously past, as described further up. In the measurement arrangement 10a according to figure 3b, an inlet window 20a and an outlet 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 by a photodetector 10c via the input window 20a through the storage tank 16a and via the output window 20b. In the measurement assembly 10a according to figure 3c, the storage tank has a reflection wall 16d in the interior, such that only a single measurement window 20 is required. In this way, the reflection-based method according to figure 3a or 3d can also be employed for a storage tank 16a. Figure 3d also shows that the interface device 32 may include 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. Furthermore, the interface device according to figure 3d includes a heating element 34 for heating the wall 16c of the cavity 16. Figure 4 shows sensitivities achievable by TDLAS in the wavelength range of relevance for a target substance. TDLAS can be performed very efficiently with commercially available VCSL or DFB laser diodes in the near infrared range (NIR range) for target substances such as CH4, CO, CO2, H2S, SO2. The gaseous target or non-target substances can efficiently and selectively be detected separately from one another in the NIR range. In order to achieve even higher sensitivities, quantum cascade lasers (QCL) can be used, for example, at the start of the mid-infrared range (MIR range). Where applicable, all the individual features shown in the working examples can be combined with and / or exchanged for one another without leaving the scope of the invention. By way of example, the measurement arrangements 10a illustrated in figures 3a-d can be used not only for the cavity 16, but also analogously for the measurement chamber 18 according to figures 2a,b. In addition, the specifications of the target substances, non-target substances, target groups and non-target groups can likewise be used in the proposed method and in the proposed apparatus. List of reference signs: 1 apparatus10 measuring device10a measurement assembly10b laser diode10c photodetector / sensor10d measurement section12 hydrogen sample14 evaluation unit16 cavity16a hydrogen storage tank16b hydrogen feed conduit16c wall16d inner wall18 measurement chamber20 optically transparent window 20a input window20b output window22 protective housing22a opening sensor24 communication unit26 recording unit 28 tunable laser diode 30 hydrogen certification module30a blockchain module32 interface device 34 heating element50 hydrogen source / supplier52 hydrogen consumer54 groups of recipients
Claims
1. A method of identifying non-electrolysis hydrogen by means of target substances from target groups, comprising the steps of:- defining (S14) a series of non-target groups, wherein each non-target group includes 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 characteristic in particular of a use of lubricants, plastic seals and / or extrinsic 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) includes a target substance, wherein the target substance is a substance from the following target groups: hydrocarbons, carbon-containing gases, sulfur-containing gases, volatile amines, formates or oxygenates;- categorizing (S40) the sample (12) as non-electrolysis hydrogen when the sample (12) includes the target substance. 2. The method as claimed in claim 1, comprising: - n-fold repetition (S31) of the step of checking (S30) for a further target substance in each case in order to test the sample (12) for a series of n target substances, where n is not less than 2. 3. The method as claimed in claim 1 or 2, comprising: - defining (S10) a reference pattern that specifies a range of proportions of the target substance, and in particular a range of proportions of the further target substances, in the sample; - optionally: associating (S12) the reference pattern with at least one non-electrolysis hydrogen production method for which the reference pattern is characteristic; and - optionally: repeating (S13) the steps of defining (S10) and associating (S12) in order to generate a series of associated reference patterns. 4. The method as claimed in any of the preceding claims, comprising:- ascertaining (S32) a proportion of the target substance in the sample (12); - matching (S34) the proportion ascertained with the range of proportions of the reference pattern; - assigning (S36) the sample (12) to the at least one non-electrolysis hydrogen production method, provided that the determined proportion lies within the range of proportions of the reference pattern; - optionally: repeating (S37) the steps of matching (S34) and assigning (S36) for the series of linked reference patterns. 5. The method as claimed in claim 3 or 4, wherein the range of proportions of the target substance in the sample (12) is 0.001 to 100 ppmv, in particular 0.01 to 1 ppmv. 6. The method as claimed in any 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 checking (S30) comprises: - constantly analyzing the sample gas flowing continuously past. 7. The method as claimed in any 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. The method as claimed in any 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. The method as claimed in any of the preceding claims, wherein the step of checking (S30) whether the sample includes a target substance is effected using absorption spectroscopy in the near- or mid-infrared region, in particular diode laser absorption spectroscopy. 10. An apparatus (1) for identifying non-electrolysis hydrogen by means of target substances from target groups, comprising - a measuring device (10) set up to detect the target substance in a hydrogen sample (12), - an evaluation unit (14) communicatively connected to the measuring device (10) and set up to categorize the sample (12) as non-electrolysis hydrogen when 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 set up to define a series of non-target groups, wherein each non-target group includes 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 characteristic in particular of a use of lubricants, plastic seals and / or extrinsic air for hydrogen transport; and updating the target groups by subtracting the defined series of non-target groups from the previous target groups. 11. The apparatus as claimed in claim 10, wherein the measuring device (10) includes a measurement assembly (10a) or a combination of a plurality of measurement assemblies (10a) from the following list: infrared gas sensor, solid-state gas sensor, Nernst sensor, exothermicity sensor, gas chromatograph, quadrupole mass spectrometer, ion mobility spectrometer. 12. The apparatus as claimed in claim 10 or 11, comprising: - a cavity (16) for storing or conveying hydrogen for a consumer (52), wherein the cavity (16) is in particular in the form of a hydrogen storage tank (16a) or a hydrogen feed conduit (16b), and - a measurement chamber (18) which is coupled to the measuring device (10) and is fluidically connectable to the cavity (16). 13. The apparatus (1) as claimed in claim 10 or 11, comprising: - a cavity (16) for storing or conveying hydrogen for a consumer (52), wherein the cavity (16) is in particular in the form of a hydrogen storage tank (16a) or a hydrogen feed conduit (16b), and - an optically transparent window (20) positionable on the cavity (16). 14. The apparatus (1) as claimed in any of claims 10 to 13, comprising a protective housing (22) accommodating the measuring device (10) and / or the evaluation unit (14), in particular wherein the protective housing (22) has been sealed by means of a seal and / or security seal. 15. The apparatus (1) as claimed in any of claims 11 to 15, having a communication unit (24) which is communicatively connected to the evaluation unit (14) and which is set up for wireless or wired data communication. 16. The apparatus (1) as claimed in claim 14 or 15, wherein the protective housing (22) has an opening sensor (22a) for detecting 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. The apparatus (1) as claimed in any of claims 10 to 16, comprising - a recording unit (26), communicatively connected to the measuring device (10), for logging and storing of measurement data (10a) from the measuring device (10), in particular wherein the recording unit (26) has a local, non-volatile data memory, and / or- an energy supply device, in particular a secondary energy supply device, which is set up to supply the apparatus (1) with electrical energy and which is positioned in particular within the protective housing (22). 18. The apparatus as claimed in any of claims 10 to 17, wherein the measuring device (10) includes a tunable laser diode (28).