EP4363637A1

EP4363637A1 - System for carrying out electrolysis

Info

Publication number: EP4363637A1
Application number: EP22737710.8A
Authority: EP
Inventors: Dietmar Neubacher; Sebastian GOTTHARDT
Original assignee: H2i Greenhydrogen GmbH
Current assignee: H2i Greenhydrogen GmbH
Priority date: 2021-07-01
Filing date: 2022-06-29
Publication date: 2024-05-08
Also published as: WO2023272326A1; US20240318322A1; CN117616155A; CA3224894A1; AT524442A4; AU2022301888A1; AT524442B1

Abstract

The invention relates to a system for carrying out electrolysis to produce oxygen and hydrogen. Said system comprises at least two electrolysis devices (1), and these electrolysis devices (1) can be supplied with an electrolyte by a common electrolyte supply device (2). Furthermore, these electrolysis devices (1) each have an electrolyte inlet (3) and an electrolyte outlet (4), which electrolyte inlets (3) and electrolyte outlets (4) are coupled to the common electrolyte supply device (2) to provide an electrolyte stream through each of the electrolysis devices (1). The system also comprises at least one electronic control device (5) and at least one flow state detection device (6) to detect the flow states of the electrolyte stream through at least one of the electrolysis devices (1). The control device (5) is designed to control at least one actuator (7) to influence the electrolyte stream through at least one of the electrolysis devices (1) using detection values from the at least one flow state detection device (6). In this way a system is created, by means of which the process of electrolysis for producing oxygen and hydrogen can be carried out in an effective manner. At the same time the system is designed for a flexible design of the process of electrolysis with at the same time high efficiency and extended service life of the individual components of the system.

Description

PLANT FOR PERFORMING AN ELECTROLYSIS

The invention relates to a plant for carrying out an electrolysis for the production of oxygen and hydrogen, as specified in the claims. The system is designed for a flexible design of the process of electrolysis for the production of oxygen and what hydrogen with high efficiency and / or extended service life of the individual components of the system.

EP1866996B9 presents a system consisting of one or more electrolysis cell subsystems and one or more fuel cell subsystems and one or more liquid modules, which system can be expanded with regard to the one or more fuel cell subsystems or the one or more electrolysis cell subsystems. In this system, at least one or at least several electrolysis cell subsystems are in fluidic and electrical communication with at least one or more liquid modules, the fluidic and electrical communication connections of the system not being limited to a specific number. Furthermore, a control device is described which activates or monitors or adjusts or deactivates all aspects of the connection between the functional parts of the system, in particular between subsystems and fluid modules. The control means is intended to detect fluctuations in individual functional parts of the system during operation and to automatically compensate for such fluctuations directly and/or indirectly, making it possible for subsystems with different technologies or from different manufacturers or types are usable. Furthermore, the control means is provided so that the system can be transferred to maintenance mode, in which a modular exchange process of subsystems of the system can be carried out. However, the usability and operating ergonomics of this known system are only partially satisfactory.

CN 111826669A describes a plant with electrolytic devices of modular design. The system shows a modularization based on the repeated construction of electrolysis devices, these electrolysis devices in turn contain several electrolysis modules, which electrolysis modules have different power ranges exhibit. The supply of an electrolyte is configured separately for each electrolysis module in this system. With regard to the supply of electrolyte, the usability of the electrolysis modules and the operating ergonomics in this system are only partially satisfactory.

The object of the present invention is to overcome the disadvantages of the prior art and to provide an electrolysis system in which the design and the process of the electrolysis for generating oxygen and hydrogen is improved.

This object is achieved by a system for carrying out an electrolysis to produce oxygen and hydrogen according to the claims.

The system according to the invention comprises at least two electrolysis devices, which electrolysis devices can be supplied with an electrolyte from a common electrolyte supply device, which at least two electrolysis devices each have an electrolyte inlet and an electrolyte outlet, which electrolyte inlets and electrolyte outlets are connected to the common electrolyte supply device to build up an electrolyte flow fluidly coupled through each of the electrolyzers, and at least one electronic controller. It should be noted at this point that, for reasons of legibility, the term electrolyte used, as is customary in technical jargon, includes both media that are considered electrolytes and alcohols or ultrapure water. At least one flow condition detection device is designed to detect the flow conditions of the electrolyte flow through at least one of the electrolysis devices. The control device is set up to control at least one actuator for influencing the electrolyte flow through at least one of the electrolysis devices on the basis of values detected by the at least one flow state detection device.

Such a system is particularly practicable because the electrolytic generation of oxygen and hydrogen by an electrical power specified for the system by an electrolysis device with the aid of the flow condition detection device with the control device by the actuator for influencing the electrolyte flow with regard to the electrolysis process in an improved manner can be carried out. In particular, an optimal process control is also possible through the disclosed system when the specified electrical power to maintain the electrolysis is not constant. hold is. In such cases, the electrolyte flow can be adapted by the actuator in a simple yet effective manner for optimal supply of the electrolysis devices. With regard to the optimal supply of the electrolysis devices, determined detection values of the flow status detection device are used to draw conclusions about the operating status of the electrolysis devices and thus subsequently identify deteriorations or changes in the electrolysis process of the electrolysis device at an early stage and counteract them with control technology. This status monitoring based on the flow status detection device is also advantageously set up to detect gradual process-related changes such as degradation of chemically active materials that are required to carry out the electrolysis over a longer period of observation, in particular over several hours, several days or several months contribute, or insufficient chemi cal reactivities of the electrolysis devices, to be able to detect reliably and easily at the same time by evaluating the recorded values.

The disclosed configuration of the system is particularly advantageous since at least two electrolysis devices can be supplied with an electrolyte from a common electrolyte supply device. Apart from the constructional and technical advantages of a joint supply by the electrolyte due to a reduced number of individual components, the electrolysis process can be improved by influencing the electrolyte flow through the claimed design of the system with at least one flow status detection device with control device and actuator, for the electrolysis devices to be supplied are precisely controlled with regard to an optimal electrolyte flow. Thus, the jointly used electrolyte supply device does not have to be matched directly to the electrolytic devices in terms of its size and supply capacity. A detection of flow conditions and reactions initiated or derived from the control device, which are carried out or implemented via the actuator, enables the electrolytic devices to be supplied in accordance with their requirements. In addition, it is advantageous that the electrolytic devices are protected against insufficient or excessive flow of electrolyte. The electrolyte flow through the individual electrolysis devices can be controlled in terms of process technology by the design of the claimed system and thus the operational safety and functional availability of the electrolytic process and the entire system. Therefore, the electrolyte supply device can also be inherently redundant and/or oversized for the respective system, for example with regard to the fluidic pressure ranges or flow rates, with the protection of the implemented electrolysis devices still being ensured by the claimed technical features.

The electrolyte supply device is therefore designed independently of the electrolysis devices with regard to the supply capacity of the electrolyte supply device, which occurs as a mutually decoupled interaction and brings with it far-reaching further advantages of the system: In addition to the number of electrolytic devices used, it can also the technological configurations or the types of electrolysis device used vary with regard to the electrolysis process for different systems, and an identically constructed or uniform electrolyte supply device can nevertheless be used for such diversely constructed systems. This advantage is primarily of economic benefit, since variants of different systems are possible with the electrolyte supply device remaining the same, which different systems are used specifically for different predetermined power ranges.

Also advantageous is an embodiment according to which it can be provided that the at least two electrolysis devices are structurally different, the different structural design of the electrolysis devices resulting in different operating ranges with regard to the electrical power of the electrolysis devices. This characteristic creates the possibility that more specific requirements for different operating strategies and thus an extended use of the system can be implemented. By way of example, a first electrolysis device with a first operating range in a first electrical power range, which is higher relative to a second electrolysis device, is used in order to use an electrical base load that is constant over a first period of time for the electrolytic production of oxygen and hydrogen; whereas the second electrolysis device is used in a second operating range in order to use electrical peak loads that additionally occur over a second period of time for the electrolytic production of oxygen and hydrogen. Overall, the overall efficiency of the system is increased over a period of time with repeatedly changing electrical load profiles, since the electrolysis devices work or are operated in their respective optimum operating or load range due to the structural measures mentioned. Another advantage of this configuration is that the second electrolysis device with a second operating range by means of the interaction of the flow state detection device, the control device and the actuator during operation to cover an electrical base load in an idle mode or standby mode, in particular a rinsing operation for a peak load that may occur with a minimal electrolyte flow can be transferred and thus the readiness to perform of the second electrolysis device is ensured, which increases the reaction speed for the provision of control services on the part of a connected electrical power network for the ready position of the electrical power.

An embodiment of the system with electrolysis devices with different operating ranges in terms of electrical power is particularly advantageous since the fluidic interaction between different electrolysis devices in terms of the electrical power and one actuator is used to influence the electrolyte flow when a new operating point of the system settles in . Since the provision of electrolyte to the electrolysis devices is delayed in time due to the inertia of the electrolyte compared to the provision of electrical power to the electrolysis devices, anticipatory control of the actuator based on the detection values of the flow condition detection device, taking into account a required electrolyte current for the respective electrolysis devices counteracted a short-term lower overall efficiency of the system. In an operation for the provision of control services with frequent coverage of peak loads, a significantly higher overall efficiency of the system is thus achieved over a longer period of operation, which makes the disclosed system as an energy storage power plant with control capacities for the electrically connected power grid particularly distinguished.

According to one development, it is possible for the at least two structurally different electrolysis devices to be fluidly connected in parallel with regard to the inflowing and outflowing electrolyte flow. This advantageous embodiment of the system means that each of the at least two electrolysis devices can be supplied directly with electrolyte from the electrolyte supply device. A precise controllability of the system, especially when the electrical wiring of the at least two electrolysis devices is designed in parallel, serial or interchangeable form. Since changing the electrical wiring from electrical parallel connection to series connection of the electrolysis devices, or in reverse order, results in changing demands on the electrolyte flow from and/or to the at least two electrolysis devices due to the change in the electrolysis process within the electrolysis devices, each of the at least two electrolysis devices can be supplied with electrolyte optimally or as required by means of the detected values via the control of the at least one actuator due to the fluidic parallel connection, in particular because the fluidic parallel connection within the electrolyte flow causes fluidly communicating repercussions in the electrolyte flow through the Change in the electrolysis process arise, which is clearly detected on the flow condition detection device and subsequently on the at least one actuator, in particular at least an electromechanical valve, can be at least partially compensated or compensated for. Another advantage is that electrolytic devices that have or cause different dynamic pressures in relation to the electrolyte flows due to their design and/or due to gradual changes in process parameters can be optimized and operated with as little failure as possible.

According to an advantageous development, it can be provided that each of the electrolytic devices is assigned a flow state detection device for detecting the electrolytic flow through the individual electrolytic devices. This creates the possibility for the electrolyte flow through the respective electrolysis device to be optimally adjustable using the at least one actuator while the at least two electrolysis devices are in operation, based on the detection values of the flow state detection devices for each of the at least two electrolysis devices. At the same time, feedback by the detection values from the flow condition detection devices about the electrolyte flow is used to ensure operational safety. In particular, the possibility of detecting incorrect operating behavior of each of the at least two electrolysis devices is created. A further advantageous effect of this further development is that, especially in the case of transient loading, the at least two electrolysis devices are operated in a specific manner, ie tailored to each of the at least two electrolysis devices, with the at least one actuator Electrolyte flow is adjusted. This is particularly advantageous if, due to demands on the system caused by a power provided by an electrical supply network that changes over time, the load requirements for the at least two electrolysis devices are different and vary over time and acceleration or Delays in the electrolyte flow while operation is continued in the optimum operating range at the same time is carried out by appropriate control of the actuator. A further advantage of this development is that the pulsations of the electrolyte flow induced by at least one actuator can be used in a targeted manner, which promotes gas bubble detachment from the components delimiting the electrolyte, while at the same time, based on the detection values of the flow condition detection devices for the individual electrolysis devices, operational safety is guaranteed. This improved detachment of gas bubbles from components adjacent to the electrolyte increases the overall efficiency of the system, since the reactivity of electrochemically active surfaces in the electrolysis devices is increased.

Furthermore, it can be expedient for the control device to be set up to use the detection values of the at least one flow condition detection device to control the at least one actuator in such a way that each of the electrolysis devices is operated within its respective predefined volume flow operating range. This embodiment of the invention has the advantage that according to the specific flow resistance of the electrolytic devices, the electrolyte flow through the respective electrolytic devices is adjusted in such a way that a flow through the electrolytic device that is optimal in terms of process technology with regard to the electrolytic process is guaranteed, while at the same time being within the respectively predefined volume flow -Operating range a component protection, in particular an overload protection with regard to electrolyte pressures, is guaranteed. Another effect of this configuration is the possibility of an individual reaction to an operational load of an electrolysis device and, associated with this, the possibility of individual regulation of the respective electrolyte flow within the respective predefined volume flow operating range for each of the electrolysis devices in order to respond to operational requirements for the process heat within an electrolysis device on the one hand to ensure or increase the operational safety and on the other hand to ensure a high efficiency of the respective electrolysis device. To- With this embodiment, the advantageous effect of a gentle operation with regard to the service life can be implemented by means of an optimal electrolyte volume flow when idling.

According to an expedient embodiment, the flow state detection device can comprise at least one pressure sensor. This makes it possible for the electrolyte volume flow to be recorded with high temporal resolution, with the result that the electrolyte flow through the at least two electrolysis devices is adapted in a particularly fast-reacting manner with regard to transient operation of the electrolysis devices and the resulting pulsations by means of the at least one actuator can. With regard to the operational safety of the system, this also has the advantageous effect that the pressure of the electrolyte can also be monitored by the flow state detection device and that safety-critical operating points or threshold values of the at least two electrolysis devices can be monitored directly by the at least one actuator can be reacted to. In addition, the possibility of more precisely detecting the flow rate of the electrolyte via a pressure measurement of the at least one pressure sensor has the advantage that the convective heat transport for targeted temperature regulation of the at least two electrolysis devices can be optimally adjusted by means of the actuator. Structurally, the use of the at least one pressure sensor results in the advantage that this at least one pressure sensor is relatively inexpensive while at the same time having high measuring accuracy, in particular in comparison to volume flow sensors.

In addition, it can be provided that the flow state detection device comprises at least one temperature sensor, which is particularly advantageous with regard to the detection of the amounts of heat absorbed or released by the electrolyte from the at least two electrolysis devices. Thus, by regulating the electrolytic flow by means of the at least one actuator, it is possible or adjustable for the at least two electrolytic devices to have an optimal or control-technically predetermined process temperature. In addition to a high degree of efficiency of an electrolysis device in operation, this has the further positive effect that another electrolysis device can then be transferred more quickly from a rinsing operation to an optimal operation by setting the optimum process temperature. Furthermore, from the standpoint of operational safety, the use of at least one temperature sensor is advantageous because Overstressing of the at least two electrolysis devices is detected and corresponding protective mechanisms are triggered by means of the at least one actuator, in particular when insufficient gas bubble detachment from the components wetted by the electrolyte threatens thermal overstressing due to the electrochemical process of the electrolysis and thus permanent damage to the system can be prevented. Structurally, the use of the at least one temperature sensor results in the advantage that this at least one temperature sensor is available as a cost-effective standard sensor with high measuring accuracy at the same time. In addition, it can also be used for chemically relatively aggressive or problematic electrolytes. A possible replacement of the at least one temperature sensor is also advantageous in terms of costs compared to other sensors for detecting the flow state.

According to one development, it is possible for at least one of the electrolysis devices to include at least two electrolysis modules that are fluidically coupled with respect to the electrolyte flow. According to this embodiment, the advantage of possible adjustments to the electrolysis process within an electrolysis device results from a changeable electrical connection of the individual electrolysis modules while the electrolyte is guided through the electrolysis modules at the same time and/or unchanged. The power spectrum of an electrolysis device can thus be changed, which has far-reaching advantages, especially in terms of recurring optimization of the entire system when the general conditions of use of the system change.

Furthermore, this embodiment of the system enables electrochemical compression and/or gas purification of hydrogen by arranging electrolysis modules in a row within an electrolysis device. This is possible through appropriate fluidic routing of the media within the electrolysis modules, with the electrolysis modules advantageously being fluidically connected in series within an electrolysis device and the at least two electrolysis devices being able to be supplied as independently operable units from the shared electrolyte supply device.

According to one development, it is possible for at least one of the at least two electrolysis modules to comprise at least one anion exchange membrane which divides a cell chamber of the at least one electrolysis module. An anion exchange membrane as charge-selective filter for the separation of anions from the electrolyte brings the decisive advantage of lower power densities with regard to the overall system, compared to PEM electrolysers, for example. The lower power density increases the safety of the entire system, since the system pressures and temperature gradients in the electrolyte flow are lower, and at the same time materials for components of electrolysis systems with anion exchange membranes can be produced in a comparatively more resource-efficient manner than, for example, materials for components of electrolysis systems with proto nominal exchange membrane. However, for an effective electrolysis process design, very thin anion exchange membranes are used, which makes sensitive monitoring and control of the electrolyte flow expedient. This problem is solved in a simple and effective manner by means of the at least one flow state detection device in combination with the at least one actuator for influencing the electrolyte flow, whereby a mutually interacting positive effect for a better overall efficiency of the system is achieved.

According to one particular embodiment, it is possible for the at least two electrolysis devices to have different electrolysis modules with regard to the cell cross section and/or with regard to a different number of cell chambers. A positive effect of this characteristic is the realization of different pressure stages of the electrolysis products. Another positive effect is that electrolytic modules that are connected in series in a fluidic manner are matched to one another according to the process-related change in the properties of the electrolyte by adjusting the number and size of cells, with the effectiveness of an electrolytic device being increased. At the same time, the at least two electrolysis devices can be coordinated with one another in terms of performance and with regard to the supply requirements for the electrolyte flow, which has the advantage that overall improved control of the system by the at least one actuator with the aid of the detection values of the at least a flow condition detection device is possible.

Furthermore, it can be provided that the electrolyte supply device comprises a storage tank for the electrolyte and an electrolyte preparation device for the electrolyte, with the storage tank ensuring the provision of the electrolyte for the at least two electrolysis devices. With this embodiment, the system is In view of the electrolyte, it can be operated as a closed system, which brings with it the advantages of a closed encapsulation in terms of plant safety. Furthermore, this embodiment is advantageous because the electrolyte supply device with the one storage tank and corresponding auxiliary elements for ensuring the supply, in particular pumps, can be implemented redundantly. At the same time, the effect occurs that the control requirement of the at least one actuator is covered by a corresponding dimensioning of the storage tank. Furthermore, it is ensured that the electrolyte in the storage tank is prepared by means of the electrolyte preparation device with simultaneous mixing in the storage tank in accordance with the process engineering specifications and thus in turn the flow state of the electrolyte stream in accordance with the requirements of the electrolysis devices for the at least two electrolysis devices by means of the actuator in optima ler way can be controlled. As an expanding synergy effect of this embodiment, the state of the electrolyte is monitored over several minutes or over several hours by means of the flow state detection device in order to estimate a necessary preparation of the electrolyte by means of the electrolyte preparation device and to trigger this necessary preparation for the system in a centralized manner by means of the control device.

In addition, it can be provided that the electrolyte supply device comprises a heat transfer device, the heat transfer device being set up to supply or extract heat from the electrolyte. The heat transfer device according to the embodiment has the advantage of the centralized, optimized preparation of the electrolyte. The heat transfer device thus enables component protection of all components wetted with electrolyte within the system on the one hand, and on the other hand heat management has a positive effect on the flow state detection device, as a reference of the state of the electrolyte collected centrally in the storage tank according to the detection values of the Flow condition detection device acts as a base. This enables the electrolytic devices to be matched all the more precisely to the operating ranges of the at least two electrolytic devices in each case by means of the at least one actuator. At the same time, the heat transfer device can also be used in conjunction with the electrolyte preparation device for the preparation and conditioning of the electrolyte. In particular, it can be advantageous if the control device is set up to specify an operating range or an operating point for at least one of the electrolysis devices and to transmit it to the at least one electrolysis device for implementation. This results in the advantageous effect that the electrolyte supply device can be operated independently of the number and power of the at least two electrolysis devices and the at least one electrolysis device can be operated accordingly in an independent mode of operation in the system.

According to one development, it is possible for the at least one electrolyte drain to be connected to the electrolyte supply device flow s via at least one return line, so that circulation of electrolyte between the electrolyte supply device and the at least one electrolysis device can be established. According to this embodiment, it is ensured that components within one of the at least two electrolysis devices that are wetted with the electrolyte are protected from excessive stress, in particular if a malfunction of another of the at least two electrolysis devices occurs and the electrolyte flow leads to a Malfunction-related feedback should come from, for example, excessive pressures. Furthermore, the amount of heat to be supplied or removed to or from the at least one electrolysis device is positively influenced, since the electrolyte is not mixed through the guaranteed circulation between the electrolyte supply device and the at least one electrolysis device. With regard to the flow state detection device, optimal control of the at least one actuator is thus possible.

In addition, it is expedient if the electrolyte outlet of the at least one electrolytic device is flow-connected to the one storage tank for the electrolyte by means of the at least one return line. The fluidic connection of the at least one return line to the one storage tank ensures the defined return of the electrolyte, which prevents an uncontrolled and/or unwanted influence on the flow of the electrolyte and the at least two electrolytic devices according to the requirements for the operating ranges of the at least two electrodes rolysis devices are optimally controlled by means of the at least one actuator.

Furthermore, it can be advantageous that the at least one electrolyte drain can be coupled to the at least one return line by means of the at least one actuator. This With regard to the electrolysis device, this measure has the decisive advantage that the electrolyte flow can be optimally adjusted with regard to the flow state via the at least one actuator, so that the electrolysis process is carried out in accordance with the requirements of the operating range of the electrolysis device. For example, a required pressure can be set in the at least one electrolyte outlet, while at the same time a required electrolyte flow is maintained by the electrolyte supply device.

In addition, it can be provided that the electrolyte flow through the at least one electrolysis device can be diverted or decoupled from a circulation line for the electrolyte by means of the at least one actuator. This has the advantageous effect that the supply of electrolyte can be provided by the electrolyte supply device regardless of the number and structural differences between the at least two electrolysis devices. This creates the possibility that the electrolyte supply device can also be oversized in a redundant manner, which does not result in any negative influence on the at least two electrolysis devices. Any supply elements for supplying electrolyte, such as pumps, can also be operated in an optimal operating range, since the circulation of electrolyte in the one circulation line can be decoupled from the supply situation of the at least two electrolysis devices through the one circulation line by means of the at least one actuator. A decisive further advantage of this configuration results from the possibility of expanding the system with further electrolysis devices, with the electrolyte supply device being able to be operated essentially independently of a gradual expansion up to a maximum possible electrolyte flow.

An advantageous development of the system is characterized in that the at least one actuator connects an electrolyte inlet of the at least one electrolysis device to the circulation line. This configuration has the advantage that an actuator reacts directly to the supply situation of the at least one electrolysis device. As a result, optimal reactions to load changes can be mapped by the at least one electrolysis device, which overall contributes to a higher overall efficiency of the system, since the electrical supply power provided is utilized in an optimal manner. At the same time, flow accelerations and/or flow decelerations wrestled, which are induced by any changes in the supply situation of the electrolyte Versor supply device, adjustable in a gradual manner, which increases the protection of the structural and associated with the electrolyte components of the at least one electro lysis device.

Also advantageous is an embodiment in which the at least one actuator can be switched to a blocked state, in which an electrolyte flow to the at least one electrolysis device can be completely suppressed. With regard to operational safety, this results in the advantage that the at least one electrolysis device downstream of the actuator in the direction of flow can be protected from the at least one actuator in the blocking state in terms of process technology, or that, conversely, the system is protected in terms of process technology in the event of a malfunction of the at least one electrolysis device. Furthermore, the automatically controllable or semi-automatically initiated blocking state enables parts of the system to be easily replaced and/or expanded, even during continued operation of the electrolyte supply device.

Provision can also be made for the at least one actuator to be formed by a controllable throttle valve line-connected to the control device, an electromagnetically actuatable directional valve, in particular a proportionally controlled directional valve, or a switching valve. An embodiment of the at least one actuator as a proportionally controlled directional control valve can be particularly advantageous, since correspondingly precise changes in the electrolyte flow can be implemented, whereby the already mentioned effects of the at least one actuator are favored and can be implemented in a particularly favorable manner in accordance with the above-mentioned embodiments.

According to an advantageous development, it can be provided that the control device is set up to receive a target operating range for the system for carrying out the electrolysis from a supply system. It can be particularly advantageous if the supply system is a large installation, by means of which several installations are operated and supplied for carrying out an electrolysis. This results in the advantageous effect that, with the aid of the detection values of the flow condition detection device, the at least one actuator operates and/or protects the system for carrying out the electrolysis independently despite a specification of the target operating range. In particular, it can be advantageous that the control device is set up to to transmit detection values of the at least one flow condition detection device to a supply system. This transmission of the recorded values means that the components of the system for carrying out the electrolysis can be protected in an extended manner. For example, a feedback can be implemented through detection values on target operating range specifications, whereby a control loop is realized with the supply system and the operation of the system for carrying out the electrolysis by means of the at least one actuator is carried out with regard to an ideal utilization of the capacities of the system.

For a better understanding of the invention, it is explained in more detail with reference to the following figures.

They each show in a greatly simplified, schematic representation:

1 shows a schematic representation of a plant for carrying out an electrolysis for the production of oxygen and hydrogen in a first embodiment;

2 shows a schematic representation of a plant for carrying out an electrolysis for the production of oxygen and hydrogen in a second embodiment;

3 shows a schematic representation of a plant for carrying out an electrolysis for the production of oxygen and hydrogen in a third embodiment;

4 shows a schematic representation of a plant for carrying out an electrolysis for the production of oxygen and hydrogen in a fourth embodiment.

As an introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numbers or the same component designations, and the disclosures contained throughout the description can be transferred to the same parts with the same reference numbers or the same component designations. The position information selected in the description, such as top, bottom, side, etc., is related to the directly described and illustrated figure and these position information are to be transferred to the new position in the event of a change in position. In Fig. 1, a first possible embodiment of a system for implementing an electrolysis for the production of oxygen and hydrogen is shown schematically. This system is set up to generate oxygen and hydrogen using an electrical load through the electrochemical process of electrolysis with the aid of an electrolyte, with the primary purpose of the system being the generation of hydrogen for further use, storage or feeding into a corresponding infrastructure is. The system shown can be operated independently or equally within a large system as a semi-autonomous system. In any case, the system serves the purpose of generating hydrogen, whereby the oxygen produced by the electrolysis process does not have to be provided for any specific further use. In particular, the system can be used to convert electrical power from renewable energies into so-called “green” hydrogen.

The illustrated configuration of the system for carrying out an electrolysis to generate oxygen and hydrogen comprises at least two electrolysis devices 1, in particular a first electrolysis device la and a second electrolysis device lb, which are preferably identical in construction, although they do not necessarily have to be identical in construction. However, the use of several electrolytic devices 1 of identical construction would result in an economic advantage, since individual components can be mass-produced at low cost. The electrolysis devices 1 can be supplied with an electrolyte from a common electrolyte supply device 2 , the electrolysis devices 1 each having an electrolyte inlet 3 and an electrolyte outlet 4 . The respective electrolyte inlet 3 and the respective electrolyte outlet 4 are coupled to the common electrolyte supply device 2 so that an electrolyte flow can be built up through the respective electrolysis device 1 . The electrolyte flow is thus provided by the electrolyte supply device 2 through the electrolysis devices 1 , with the electrochemical process of the electrolysis being carried out by the electrolysis device 1 in each case.

Furthermore, the configuration of the system shown comprises at least one electronic control device 5, which controls the system. This electronic control device 5 can have a communication connection 21 and an electrical supply line 22 . Thus, the electronic control device 5 can control the facility according to a specification of an operating range for the facility and according to the specification of an electric load for the facility. As mentioned above, this can be advantageous if the illustrated Embodiments of the system are integrated as a subsystem within a large system, with corresponding specifications being provided by the large system by means of the communication link 21 and the electrical supply line 22 .

The system also includes a flow condition detection device 6 for detecting the flow conditions of the electrolyte flow through at least one of the electrolysis devices 1. The control device 5 of the system is also set up to use the detected values of the at least one flow condition detection device 6 to detect at least one actuator 7 for Influencing the electrolyte flow through at least one of the electrolysis devices 1 to control. For this purpose there are corresponding control connec tions 23 between the control device 5 and the respective components of the system.

An electrolyte flow can thus advantageously be set up according to the operating ranges or operating points of the at least two electrolysis devices 1, monitored using the at least one flow state detection device 6 and/or manipulated using the at least one actuator 7 or influenced in terms of process technology. The electrolyte thus provided in the electrolysis devices 1 is used in order, with the aid of an electrical load provided on the electrolysis devices 1 by means of the control connections 23, to carry out an electrolysis for generating oxygen and hydrogen. In accordance with the advantageous effects described above, this creates the possibility of operating the system in an optimal manner, whereby the possibility can also be created that the system, in accordance with the specifications of the communication link 21 and the electrical supply line 22, can perform electrolysis by inherently independent operation but in conjunction with a large scale facility.

According to the configuration of the system shown in FIG. 1, a product gas collection line 15 can be used to remove the hydrogen produced from the electrolysis devices 1 for any further use. The product gas collection line 15 can also make it possible for the electrolysis devices 1 to be flushed with fluid.

The electrolyte supply device 2 can comprise a storage tank 10 for the electrolyte and an electrolyte preparation device 11 for the electrolyte. So can the provision of the electrolyte for the at least two electrolysis devices 1 can be ensured by means of the storage tank 10 . Provision can also be made for the at least one electrolyte outlet 4 to be flow-connected to the electrolyte supply device 2 via at least one return line 13, so that circulation of electrolyte between the electrolyte supply device 2 and the at least one electrolysis device 1 can be established. In one possible configuration of the system, the electrolyte can thus be fed from the electrolysis devices 1 into the storage tank via at least one return line 13

10 are returned, since the electrolyte outlet 4 of the at least one electrolysis device 1 can be flow-connected to the one storage tank 10 for the electrolyte by means of the at least one return line 13 . There is thus the possibility that the electrolyte is fed back into the storage tank 10 from the electrolysis devices 1 and that the oxygen produced by the electrolysis can be discharged from the storage tank 10 by means of an oxygen line 16 . Since the chemical properties of the electrolyte are changed by the electrolysis, the electrolyte processing device 11 can be used to process the electrolyte again, with a corresponding additive supply line 17 being able to be used.

Furthermore, the electrolyte supply device 2 can include a heat transfer device 12, wherein the heat transfer device 12 is set up to supply or extract heat from the electrolyte. This heat transfer device 12 can be used according to the advantages described above. As a further advantageous additional function, the heat transfer device 12 can support the preparation of the electrolyte by means of the electrolyte preparation device

11 be made more performant. For example, by using the heat transfer device 12, the electrolyte can be stimulated by heating to a material separation by evaporation, as a result of which the chemical properties of the electrolyte can be changed. Further advantageous effects of this embodiment are the component protection of the components wetted with electrolyte and the increase in the reaction speed of the electrolysis devices 1 and, as a result, more efficient operation of the same.

In order to extend the functionality of the heat transfer device 12 and the storage tank 10, the system can be supplemented by a heat exchange medium supply line 18 and a heat exchanger medium discharge line 19 and a storage tank emptying line 20 will. Thus, the heat transfer device 12 can be operated in an effective manner with the aid of a heat exchange medium. The storage tank 10 can also be completely emptied in order, for example, to completely exchange the electrolyte or to prepare it externally. Furthermore, a possible embodiment is conceivable in which at least two storage tanks are used if multi-flow operation with, for example, two electrolytes with different or the same chemical properties is used. With regard to this possible embodiment, it should be noted that other necessary structural measures, such as at least two electrolyte inlets and outlets, must be provided. With regard to the storage tank 10, a possible embodiment is also conceivable, in which the additive supply line 17 as a multiple use can both allow the supply of the additive and also allow the storage tank 10 to be emptied.

This embodiment of the system, as shown in Fig. 1, enables effective operation of the system, in particular since the control device 5 is set up to control the at least one actuator 7 based on the detection values of the at least one flow condition detection device 6 in such a way that each of the Electrolytic devices 1 can be operated within half of their respective predefined or optimal volume flow operating range. The flow state detection device 6 can include at least one pressure sensor and/or one temperature sensor. As already described above, the use of these sensors can be advantageous for the system due to a number of effects.

In Fig. 2, a further and possibly for itself independent embodiment of the situation is shown, again for the same reference numerals or component designations as in the previous Fig. 1 are used for the same parts. In order to avoid unnecessary repetitions, reference is made to the detailed description of the preceding FIG. 1 and the preceding introduction to the description. As shown in FIG. 2, a possible configuration of the system can be that the electrolyte flow through the at least one electrolysis device 1c can be diverted/decoupled from a circulation line 14 for the electrolyte by means of the at least one actuator 7a. Provision can be made here for the at least one actuator 7a to connect an electrolyte inlet 3 which connects at least one electrolysis device 1c to the circulation line 14 . Correspondingly, the effects described above result from this configuration of the system several advantages in terms of their operation. Furthermore, the system can contain a pumping device 24 for supplying the electrolytic devices 1 with electrolyte in a redundant manner. For the pump device 24 it should be noted that it can be installed on the suction side or on the pressure side in relation to the direction of flow for supplying the electrolytic devices with electrolyte. As already described above, the circulation line 14 enables the electrolyte to be supplied by the electrolyte supply device 2 regardless of the number and structural differences between the at least two electrolysis devices 1 . For example, the pumping device 24 can also be oversized in order to ensure that the system can be expanded with several electrolytic devices 1 while at the same time complying with all the requirements of the electrolytic devices 1 for the electrolyte flow, particularly in terms of flow technology. In the same way, the pump device 24 can be expanded in a possible embodiment to include a pump for the constant overturning and/or circulation of the electrolyte. Such a configuration has the advantageous effect that the flow of electrolyte is kept in constant motion, and thus the accumulation of gas bubbles on surfaces wetted by the electrolyte is advantageously reduced or prevented.

It is also conceivable that in a possible advantageous embodiment the at least one actuator 7b is provided in the return of the circulation line. Thus, for example, if the internal resistances of the electrolysis devices 1 are known, an ideal operating point of the at least two electrolysis devices 1 with regard to the efficiency can be set. Above all, this can bring far-reaching advantages in conjunction with a corresponding control of the pump device 24, since this enables an extremely precise dosing of the electrolyte flow. It should also be noted that the arrangement of the at least one actuator 7b shown in FIG. 2 is an example of an embodiment, so the possibility of arranging this actuator in the inlet of the circulation line can also be advantageous. At this point it should also be noted that the pumping device 24 can be designed to suck or pump with respect to the direction of supply with electrolytes and that no preferred arrangement is provided with respect to the direction of supply with electrolytes. This is to be noted above all in relation to FIG. 1 . With regard to a structurally different design of the electrolysis devices 1, it can be provided that the different structural design of the electrolysis devices 1 results in a different operating range with regard to the electrical power of the electrolysis devices 1. As shown in FIG. 2, an embodiment of the system can also be advantageous in which at least one of the electrolysis devices 1, for example the electrolysis device 1d as shown, comprises at least two electrolysis modules 8 fluidically connected in series with regard to the electrolyte flow. This results in advantageous effects, as already described above. It can also be advantageous that the different electrolysis modules 8 are designed with regard to the cell cross-section and/or with regard to a different number of cell chambers, with at least one of the at least two electrolysis modules 8 comprising at least one anion exchange membrane 9 which divides the cell chamber. Thus, with the configuration of the system shown, an increased degree of flexibility can be created with regard to covering a broad operating range of the system. This can also create further advantageous properties of the system, such as processing the hydrogen gas in terms of its pressure level and purity within an electrolysis device 1. For example, the possibility of processing can be created by the described serial arrangement of the electrolysis modules 8, it being conceivable that an electrolysis module 8 can also contain a large number of anion exchange membranes 9, which anion exchange membranes 9 can thus carry out an electrolytic process in a number of cell chambers lined up next to one another. In this way, the advantageous configuration can be created that the routing of the electrolyte and the routing of the electrolysis products is designed within an electrolysis module 8 in such a way that hydrogen gas can be generated with increased purity and at increased pressure compared to an electrolysis with only one cell chamber.

FIG. 3 shows a further embodiment of the system, which may be independent in itself, with the same reference numbers or component designations as in the previous FIGS. 1 and 2 being used for the same parts. In order to avoid unnecessary repetitions, reference is made to the detailed description of the preceding FIGS. 1, 2 and the preceding introduction to the description. As shown in Fig. 3, a possible embodiment of the system can be that by means of the at least one actuator 7, the at least one electrolyte outlet 4 with the at least one Return line 13 can be coupled. As already described, this advantageous configuration allows the electrolyte flow to be controlled in an effective manner. As already mentioned in the introduction to the description and in FIG are fluidly connected in series. According to the schematic representation, the electrolysis module 8c and the electrolysis module 8d can differ with regard to the cell cross section and/or with regard to a different number of cell chambers. As already described in detail above, this possible embodiment of the system can have several advantageous effects. On the one hand, due to the structural differences between the electrolysis modules 8, different requirements for the electrolysis process can be mapped. For example, by suitably lining up cell chambers with a first cell cross-section, different pressure stages and degrees of purity of the hydrogen gas can be implemented. On the other hand, with regard to the serial arrangement of the at least two electrolysis modules 8, the second electrolysis module 8d, which is serial in the flow direction of the electrolyte, can be operated in a high-performance manner by suitably adapting the number of cells and cell cross-section, even if the electrolyte already contains process-related gases may include from the first electrolysis module 8c. Furthermore, by suitably adapting the number of cells and cell cross-sections of the at least two electrolysis modules 8, the operating range and/or the most effective operating point of the electrolysis device lf can be optimally matched to the requirements of the system, for example if the system is integrated into a large-scale system as a Unit with specific requirements is to be integrated. At this point, reference should also be made to the above-described advantageous effects of the system according to the invention, with regard to optimal coordination based on specifications for a variable electrical load on the part of a connected electrical network and the resulting control capability of the system.

4 shows another embodiment of the system, which may be independent in itself, with the same reference numbers or component designations as in the previous FIGS. 1, 2 and 3 being used for the same parts. In order to avoid unnecessary repetition, reference is made to the detailed description of the previous ones Fig.l, Fig. 2, Fig. 3 and the previous introduction to the description pointed out or Be taken train. As shown in Fig. 4, a possible configuration of the system can be that at least one actuator 7 can be converted into a blocking state in which an electrolyte flow to the at least one electrolysis device 1, to which the at least one actuator 7 is assigned, completely is preventable. An example of such a possible embodiment is illustrated by actuator 7f in FIG System can remain operable in an optimal manner without restrictions. In addition to the advantageous effects already described, this can open up the possibility of maintenance work or ensure the interchangeability of electrolysis devices 1 with continued operation, with the operating range of the system still being able to be kept in high-performance operation in accordance with the inventive design of the system.

Furthermore, the possible configuration of the system in FIG. 4 shows the possibility of expanding the system according to the invention. For example, the system can comprise a plurality of electrolysis devices 1g, 1f and 1h, with these electrolysis devices 1 in turn being able to contain a plurality of electrolysis modules 8e to 81, which are also structurally different. With this possible constellation, a gradual and precise tuning of the system to operational requirements can take place, while at the same time an extension with additional electrolytic devices 1 up to the utilization limit of the electrolytic supply device 2 is not ruled out. In addition to the advantages already described above, this embodiment shown schematically can be particularly favorable if the disclosed system is operated in a semi-autonomous manner in the network of a large system by means of a higher-level system that can take over control and load distribution tasks. This possible embodiment is indicated by the exemplary supply system 25 shown in FIG. 4 . As described, the supply system 25 can be provided by a large system.

The exemplary embodiments show possible variants, it being noted at this point that the invention is not limited to the specifically illustrated variants of the same ben, but rather that various combinations of the individual variants are possible and this possibility of variation is due to the The teaching of technical action through a concrete invention lies within the ability of the person skilled in the art working in this technical field.

The scope of protection is determined by the claims. However, the description and drawings should be used to interpret the claims. Individual features or combinations of features from the different exemplary embodiments shown and described can represent independent inventive solutions. The task on which the independent inventive solutions are based can be found in the description.

According to the list of reference numbers, terms from the list of reference numbers are used with and/or without a specific index in the description of the disclosure. If an exact differentiation of the terms with regard to their specific form is not necessary, no indices are used. Conversely, for example, an electrolysis device lg is differentiated from an electrolysis device lf according to the respective description, with both still being electrolysis devices 1 .

All information on value ranges in the present description is to be understood in such a way that it also includes any and all sub-ranges, e.g. the information 1 to 10 is to be understood as including all sub-ranges, starting from the lower limit 1 and the upper limit 10 i.e. all sub-ranges start with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

Finally, for the sake of clarity, it should be pointed out that some elements are shown not to scale and/or enlarged and/or reduced in order to better understand the structure. List of reference numbers Electrolysis device Electrolyte supply device Electrolyte inlet Electrolyte outlet Control device Flow state detection device Actuator Electrolysis module Anion exchange membrane Storage tank Electrolyte treatment device Heat transfer device Return line Circulation line Product gas collection line Oxygen line Additive feed line Heat exchange medium supply line Heat exchange medium discharge line Storage tank emptying line Communication connection Electrical supply line Control connections Pumping device supply system

Claims

P atentClaims

1. Plant for carrying out an electrolysis to produce oxygen and hydrogen, comprising at least two electrolysis devices (1), which electrolysis devices (1) from a common electrolyte supply device (2) can be supplied with an electrolyte, which electrolysis devices (1) at least each have an electrolyte inlet (3) and an electrolyte outlet (4), which electrolyte inlets (3) and electrolyte outlets (4) are fluidically coupled to the common electrolyte supply device (2) to build up an electrolyte flow through each of the electrolysis devices (1), and at least one electronic control device (5), characterized in that at least one flow condition detection device (6) is designed to detect the flow conditions of the electrolyte stream through at least one of the electrolysis devices (1), and in that the control device (5) is set up to detection values of the least s a flow state detection device (6) to control at least one actuator (7) for influencing the flow of electrolyte through at least one of the at least two electrolytic devices (1).

2. System according to claim 1, characterized in that the at least two electrolysis devices (1) are structurally different, the different structural design of the electrolysis devices (1) resulting in a different operating range with regard to the electrical power of the electrolysis devices (1). .

3. Plant according to claim 1 or claim 2, characterized in that the at least two electrolysis devices (1) are fluidically connected in parallel with regard to their inflowing and outflowing electrolyte streams.

4. Plant according to one of the preceding claims, characterized in that each of the electrolysis devices (1) is assigned a flow state detection device (6) for detecting the solution of the electrolyte flow through the individual electrolysis devices (1).

5. System according to one of the preceding claims, characterized in that the control device (5) is set up to control the at least one actuator (7) based on the detection values of the at least one flow condition detection device (6) in such a way that each of the electrolysis devices (1) is operated within its respective predefined volumetric flow operating range.

6. Installation according to one of the preceding claims, characterized in that the flow condition detection device (6) comprises at least one pressure sensor.

7. Installation according to one of the preceding claims, characterized in that the flow condition detection device (6) comprises at least one temperature sensor.

8. Plant according to one of the preceding claims, characterized in that at least one of the electrolysis devices (1) comprises at least two electrolysis modules (8) which are fluidically coupled with respect to the electrolyte current.

9. Plant according to claim 8, characterized in that at least one of the at least two electrolysis modules (8) comprises at least one anion exchange membrane (9) which divides a cell chamber of the at least one electrolysis module (8).

10. Plant according to claim 8, characterized in that the at least two electrolysis devices (1) have different electrolysis modules (8) with regard to the cell cross-section and/or with regard to a different number of cell chambers.

11. System according to one of the preceding claims, characterized in that the electrolyte supply device (2) comprises a storage tank (10) for the electrolyte and an electrolyte preparation device (11) for the electrolyte, the storage tank (10) providing of the electrolyte for the at least two electrolysis devices (1).

12. Plant according to one of the preceding claims, characterized in that the electrolyte supply device (2) comprises a heat transfer device (12), wherein the heat transfer device (12) is set up to supply and/or extract heat from the electrolyte.

13. System according to one of the preceding claims, characterized in that the control device (5) is set up to specify an operating range or operating point for at least one of the electrolysis devices (1) and to transmit it to the at least one electrolysis device (1) for implementation.

14. System according to one of the preceding claims, characterized in that the at least one electrolyte outlet (4) via at least one return line (13) with the electrolyte supply s device (2) is flow-connected, so that a circulation of electrolyte between the Electrolyte supply device (2) and the at least one electric lysis device (1) can be built up.

15. Plant according to claim 14, characterized in that the electrolyte outlet (4) of the at least one electrolysis device (1) is flow-connected by means of the at least one return line (13) to a storage tank (10) for the electrolyte.

16. Plant according to claim 14, characterized in that the at least one electrolyte outlet (4) can be coupled to the at least one return line (13) by means of the at least one actuator (7).

17. Plant according to one of the preceding claims, characterized in that the electrolyte flow through the at least one electrolysis device (1) by means of the at least one actuator (7) from a circulation line (14) for the electrolyte can be branched off / coupled.

18. Plant according to claim 17, characterized in that the at least one actuator (7) connects an electrolyte inlet (3) of the at least one electrolysis device (1) to the circulation line (14).

19. Plant according to one of the preceding claims, characterized in that the at least one actuator (7) can be converted into a blocked state in which an electrolyte flow to the at least one electrolysis device (1) can be completely suppressed.

20. System according to one of the preceding claims, characterized in that the at least one actuator (7) is formed by a controllable throttle valve connected to the control device (5), an electromagnetically actuable directional valve, in particular a proportionally controlled directional valve, or a switching valve .

21. Plant according to one of the preceding claims, characterized in that the control device (5) is set up to receive a target operating range for the plant for carrying out the electrolysis from a supply system (25).

22. Plant according to one of the preceding claims, characterized in that the control device (5) is set up to transmit detection values of the at least one flow state detection device (6) to a supply system (25).