Water supply preparation method and water supply preparation system for alkaline electrolytic cell systems

Abstract

A water supply preparation system for a water electrolytic cell, comprising a product gas adjustment system adapted to produce hydrogen and oxygen in one or more pressurized electrolytic cell stacks (2) using alkaline water, and having a safety valve blowout material flow pipe (11) connected to a water supply container (9), and / or a reduced pressure flow pipe (31) from a gas washing container connected to a water supply container (9).

Description

Technical Field

[0001] The present invention relates to a method for preparing feed water for an alkaline water electrolysis system and a feed water preparation system in a water electrolysis cell, which is adapted to generate hydrogen and oxygen in one or more pressurized electrolyzer stacks using alkaline water and also includes a product gas conditioning system.

Background Art

[0002] In a water electrolysis cell that generates hydrogen and oxygen by splitting water, particularly in a cell that uses a pressurized, alkaline-rich aqueous solution as an electrolyte, it is desirable that the alkaline portion of the electrolyte remains within the electrolysis system and is not washed out of the unit with the product gases of hydrogen and oxygen. In such systems today, a design pressure of up to 50 bar is common, and system pressures of about 35 - 40 bar are often seen. Also, systems with a maximum of 90 - 120 bar have been designed. The high pressures in such systems allow the generated gases to exit the electrolysis unit at system pressure, and users of one or more gases prefer to receive hydrogen or oxygen at elevated pressure. Safety measures such as safety valves are necessary to ensure that pressure can be released if the system pressure or design pressure is exceeded, for example due to valve failure, and typically the blow-off material flow from such valves is released directly to the atmosphere. Attempts to capture the alkaline components and / or fluids in such blow-off material flows have failed. Also, when this type of system is set to a safe state, nitrogen or a similarly inert gas is conventionally introduced into the pipes and vessels so that trace amounts of oxygen and hydrogen do not remain within the plant. This so-called purge process can also wash away any alkaline particles that may have crystallized along a particular length of piping, and this alkaline component is usually lost as all purge gases are conventionally discharged directly to the atmosphere. Further, such systems may include high-pressure gas-containing vessels that need to be depressurized to put the system in a safe state, and if such depressurized gas is discharged to the atmosphere, trace amounts of alkaline components may escape with such gas flow.

Summary of the Invention

[0003] In the above-described type of alkaline electrolytic cell system, a water supply preparation method is provided, wherein one or more electrolytic cell stacks each have at least one diaphragm separating oxygen-generating half cells from hydrogen-generating half cells, and all further oxygen-generating half cells deliver an oxygen-electrolyte mixture, and all hydrogen-generating half cells deliver a hydrogen-electrolyte mixture, thereby further separating each of the above mixtures into a stream mainly of oxygen-generating gas and an electrolyte stream depleted of oxygen, and a stream mainly of hydrogen-generating gas and an electrolyte stream depleted of hydrogen, thereby replenishing the electrolyte stream with water from a water supply container.

[0004] According to the present invention, the water supply container receives a discharge material flow from at least one safety valve when the valve is activated, and / or receives a discharge material flow from the depressurization of a pressurized container holding the generated gas when the depressurization of the system is initiated.

[0005] If the safety valve in question is a separator container safety valve, the material flow blown out from it is likely to contain a high proportion of alkali-rich water mixed with the respective generated gases. Entering the inside of a water tank provides a means for at least partial separation between the fluid and gaseous portions of such a material flow, and it is relatively easy to retain the liquid portion inside the water container, thereby also retaining the alkaline component of the flow.

[0006] A similar opportunity arises from a material flow that naturally occurs when the process vessel, which is part of the gas regulating line downstream of the separator, needs to be depressurized. This need arises whenever the system needs to be shut down and brought to a safe state. Similarly, to avoid introducing alkaline elements into the environment outside the system, the material flow resulting from a depressurization event is also piped to a feedwater tank, thereby easily trapping any liquid containing potentially trace amounts of alkaline components, as well as any potentially solid particles in the material flow, inside the feedwater tank.

[0007] In one embodiment, the discharge material flow is directed tangentially onto the inner cylindrical surface inside the water supply container, causing it to form a cyclone, which allows any solids and liquids to settle on the inner cylindrical surface, and further, allows gases to exit the container through an outlet pipe positioned coaxially with the central axis of the inner cylindrical surface.

[0008] The task of separating liquid and / or solid elements from a gas can be performed in any number of ways, but in this case, when the blown material flow and / or depressurized flow reach the feedwater tank at a considerable speed, the formation of a cyclone flow is relatively easy to achieve and occupies less space compared to other types of separation methods.

[0009] In one embodiment of the water supply preparation method, the water supply container receives alkali-containing drain resulting from filtration and drying processes performed for each generated gas stream.

[0010] This provision also helps ensure that alkali-containing substances are maintained within the system. Several drains are typically embedded in the system's gas regulator, each supplying the optimal components to the flow of liquid material containing at least trace amounts of alkaline components from the electrolyte, piped back to the water tank to ensure that the alkaline portion is not lost from the system. The return of the drains to the water tank also helps keep water consumption low and closer to the ideal minimum corresponding to the hydrogen and oxygen produced.

[0011] In one embodiment of the water supply preparation method, the water supplied from the water supply container and any alkaline materials that may be dissolved therein are pressurized and used in the generated gas washing process in the gas washing container, and any alkaline substances that may be carried in the generated gas stream are dissolved in the pressurized water, thereby the water, which has thus become even more alkaline, flows into each separator to replenish the water lost during the electrolysis process in the half cell.

[0012] Within the washing container, the generated gas is completely mixed with the fluid inside the container, thereby trapping electrolyte and alkaline component particles and / or droplets within the washing container fluid. One way to achieve mixing is by allowing small gas bubbles to permeate the liquid column. In this case, the liquid water comes from a water tank, and the water in the washing container is further enriched with alkaline components, thereby keeping these alkaline components trapped within the system.

[0013] In one embodiment of the water supply preparation method, a first water supply container receives fluid and gas from a hydrogen preparation system and delivers water to a hydrogen gas cleaning process, and a second water supply container receives fluid and gas from an oxygen preparation system and delivers water to an oxygen gas cleaning process.

[0014] In some electrolytic cell systems, the alkaline liquid stream, depleted of gas from the gas separator, is mixed before being reinjected into one or more electrolytic cell stacks. In such systems, water from a scrubbing vessel can be pumped into this mixed stream from two separators. However, in this example, there are two separate electrolyte streams, a hydrogen-producing stream and an oxygen-producing stream, and each product gas stream is further equipped with an equivalent gas conditioning process. Thus, each conditioning process is provided with a gas scrubbing vessel, which then delivers a stream of water with increased alkalinity to its respective separator. In this way, cross-contamination between gases in the electrolyte is minimized.

[0015] In one embodiment, the object of the present invention is obtained by a feedwater preparation system in an alkaline water electrolysis system, which is adapted to produce hydrogen and oxygen in one or more pressurized electrolytic cell stacks using alkaline water, each stack having at least one diaphragm separating the oxygen-producing half-cell from the hydrogen-producing half-cell, thereby adapting all oxygen-producing half-cells to deliver an oxygen-electrolyte mixture, and all hydrogen-producing half-cells to deliver a hydrogen-electrolyte mixture, thereby sending each of the mixtures by pipe to its respective separator, where it is separated into an electrolyte flow mainly consisting of oxygen-producing gases and an oxygen-depleted electrolyte flow, and a electrolyte flow mainly consisting of hydrogen-producing gases and a hydrogen-depleted electrolyte flow, thereby replenishing the electrolyte flow with water from a feedwater container, and the alkaline water electrolysis system further comprises a product gas preparation system.

[0016] According to this aspect of the present invention, the safety valve discharge material flow pipe is connected to a water supply container, and / or the pressure reduction flow pipe from the gas cleaning container is similarly connected to a water supply tank.

[0017] Both the blow-off flow and the depressurized flow from the safety valve may contain materials with trace amounts of alkaline components in the electrolyte. Therefore, the connection between these two alkaline material sources and the water container ensures that the amount of alkaline material lost from the system is minimized. The alkaline component is conventionally potassium or sodium. In this example, potassium is used.

[0018] In one embodiment of the water supply preparation system, the safety valve pipe and material flow are tangentially connected to the cylindrical portion inside the water supply container to discharge the material flow along the inner cylindrical surface inside the water supply tank, and the outlet pipe is provided coaxially with the cylindrical axis of the inner cylindrical surface inside the water supply container and is directly connected to the atmosphere.

[0019] This configuration ensures a cyclone-like flow pattern for the gases and fluids added to the feedwater tank. This cyclone-like flow pattern also helps ensure that solids or liquids in the material flow entering the feedwater container settle on the cylindrical portion within the container, flow down from the cylindrical portion through the cyclone opening into the liquid held in the feedwater tank, thereby remaining within the container and not being washed away by the gas flow exiting the container through coaxially arranged pipes. The pressure difference between the incoming discharge material and the low pressure within the feedwater container also ensures the cyclone effect. This low pressure within the feedwater container is also maintained by having an outlet pipe that opens to the atmosphere, and this outlet pipe has a flow area at least several times larger than the flow area of ​​the safety valve pipe. The low pressure maintained within the feedwater tank also ensures that the alkaline-containing water in the tank does not flow back into the pure water pipe and the pure water treatment system, which is also connected to the feedwater tank, under any circumstances.

[0020] In one embodiment of the water supply preparation system, the water supply container is connected to a drain from a further gas regulator in the gas preparation system.

[0021] By installing these additional connections, it is ensured that only small amounts of alkaline components leave the system.

[0022] In one embodiment of the water supply preparation system, a water outlet pipe from the bottom of the water supply container is connected to a water supply pressure pump and adapted to supply a water supply material flow into a gas scrubbing container. Furthermore, the pipe interconnects the gas scrubbing container and a gas separator, so that water from the water supply container is sent through the pipe through the gas scrubbing device and flows into the gas separator as an alkaline water flow, thereby replenishing the water lost in the water electrolysis process and ensuring that any alkaline substances that may have escaped from the gas separator container with the gas flow are returned to the system's electrolyte.

[0023] A pressure pump is inserted into the pipe between the feedwater container and the gas scrubbing container when the feedwater container is open to the atmosphere and therefore maintained at ambient pressure, while the gas scrubbing container is maintained at system pressure, thereby increasing the pressure of the feedwater material flow supplied to the gas scrubbing container. The fluid flow from the gas scrubbing container into the separator ensures that the alkaline components washed away from the generated gas are returned to the electrolyte flow entering and leaving the stack.

[0024] In one embodiment of the water supply preparation system, a first water supply container is connected to the drain and filter of a hydrogen gas preparation system and further connected to a hydrogen gas cleaning container to supply water thereto, and a second water supply container is connected to the drain and filter of an oxygen gas preparation system and further connected to an oxygen gas cleaning container to supply water thereto.

[0025] In both hydrogen gas and oxygen gas scrubbing systems, the use of a water container ensures that alkaline components are not washed away from the system. In many cases, the generated oxygen gas is not used for industrial purposes and is released into the atmosphere. However, scrubbing of this generated gas may still be necessary, and therefore it is advantageous to recover the alkaline components that escape the separation process along with the generated oxygen.

[0026] Various exemplary and non-limiting embodiments relating to both structure and operation, along with their additional purposes and advantages, will be best understood from the following description of specific exemplary and non-limiting embodiments, when read in conjunction with the accompanying drawings.

[0027] When used herein, the terms “comprises,” “comprising,” and “comprised of” are to be interpreted as specifying the presence of the described features, integers, steps, or components, but it should be emphasized that this does not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof.

[0028] Hereinafter, the present invention will be described in more detail by referring to the embodiments shown in the accompanying drawings. It should be emphasized that the embodiments shown are for illustrative purposes only and should not be used to limit the scope of the present invention.

Brief Description of the Drawings

[0029] [Figure 1] It is a flowchart with a water supply container and the main components and material flows associated with the shown container. [Figure 2] It is a horizontal sectional view from above the water supply tank. [Figure 3] It is a 3D vertical sectional view of the tank. [Figure 4] It is a schematic diagram of the main part of the sectional view of the tangential inflow path. [Figure 5] It is a schematic diagram of an alkaline water electrolysis system. [Figure 6] It is an ideal diagram of the built-in cyclone inside the water supply tank. [Figure 7] It is a schematic diagram of an electrolytic cell having only a single cell 22. [Figure 8] It is a diagram showing an electrolytic cell system as shown in FIG. 5 but including only the hydrogen adjustment part of the system.

Modes for Carrying Out the Invention

[0030] Figure 5 schematically shows some of the main components of the alkaline water electrolysis system 1. Four electrolytic cell stacks 2 are shown, labeled “cell stack 1,” “cell stack 2,” “cell stack 3,” and “cell stack 4.” Each cell stack 2 comprises several single cells 22. Figure 7 schematically shows one such cell. Each single cell 22 comprises an oxygen-producing half-cell 4 and a hydrogen-producing half-cell 5, and a diaphragm 3 that separates the two half-cells 4 and 5 and ensures that the gases produced by the cells 22, i.e., oxygen and hydrogen, are not mixed. The electrolytic cell stack 2 preferably comprises a predetermined number of cells 22, and the electrolyte and product flow entering and leaving the cells 22 within each stack 2 is piped to each half-cell 4 and 5 through four stack internal manifolds (not shown), as is well known in the art.

[0031] As shown in Figure 5, the stack external delivery manifold pipes the deliveries of oxygen-producing gas and electrolyte mixture 27 and hydrogen-producing gas and electrolyte mixture 28 from each stack 2 to their respective separator containers 23, 24. A similar supply manifold ensures that the depleted electrolytes 25, 26 are returned to the stacks 2. The stack external manifold structure is seen positioned between the stacks in Figure 5, and this manifold structure allows four stacks 2 to be driven by only two common separator containers 23, 24. Any number of stacks can be used with two separators, but increased piping length is usually a limitation, and in one embodiment, as shown in Figure 8, six stacks 2 are disclosed with one separator 24. A second separator 23 must also be part of such a system, but is not shown in Figure 8.

[0032] The electrolyte supplied to stack 2 is replenished with alkaline water 13, which is piped from each gas scrubbing container to separators 23 and 24. Figures 5 and 8 show the gas scrubbing container 21, which receives and exits the hydrogen-producing gas stream 7 from the hydrogen separator container 24, but where trace amounts of alkali content are substantially removed from the electrolyte. The alkali content in the hydrogen (and oxygen)-producing gas streams 7 and 6 directly from separators 23 and 24 is too high for most uses of the hydrogen and oxygen-producing gases. However, by capturing this alkali content in the aqueous phase within the gas scrubbing container 21, the produced gases will not contain this alkali content. By further supplying alkaline water 13 from the scrubbing container 21 to the separator 24 to replenish the water lost in the electrolysis process, the alkaline components in the electrolyte stream remain within the alkaline water electrolysis system 1.

[0033] In Figures 8, 5, and 1, a water supply container 9 is disclosed, which is the recipient of the blown material flow 11 from the safety valve 12 of the hydrogen gas treatment system, and also the recipient of one or more fluid drain outflows 8 resulting from the hydrogen gas treatment. The water supply container 9 also delivers water 20 to the hydrogen gas scrubbing container 21, and the further alkaline water flow 13 is piped from the gas scrubbing container 21 to the hydrogen gas separator 24 as described above.

[0034] Similarly, the oxygen gas separator container 23 is configured to deliver oxygen via a pipe to an oxygen cleaning container (not shown, but corresponding to a cleaning container 21 for hydrogen and connected to the oxygen separator container 23), and is further connected via this oxygen cleaning container to an oxygen water supply container (not shown, but corresponding to a hydrogen water supply container 9 and delivering water to the oxygen cleaning container), which is the recipient of the gas and / or water streams resulting from the oxygen treatment, as well as the blown-out material streams from one or more safety valves in the oxygen treatment system, such as a safety valve (not shown) on the oxygen gas separator 23.

[0035] At every closure of the system, depressurization is required for safety reasons, and containers such as the gas scrubbing container 21 also need to be depressurized. This generates a material flow 31 containing trace amounts of water from the scrubbing container 21 and trace amounts of alkali in the electrolyte used therein. This flow 31 is then added to the flow line or pipe 11 originating from the safety valve 12 on the separator in question. This is shown in Figures 8 and 5.

[0036] Both the hydrogen-producing gas and the oxygen-producing gas are processed in several steps, firstly, a separation step in separators 23 and 24, followed by gas washing in their respective gas washing containers, and then, for the hydrogen side, further gas regulators such as filters, dryers, and coolers shown by container 32 in Figure 8, can be used to ensure gas delivery 33 outside the system according to a given customer quality requirement, or environmental requirements if the destination of the gas, such as oxygen, is the atmosphere. Some of these processes, such as drying, result in by-products such as water containing trace amounts of alkaline components. All such by-products are safely piped back to their respective water containers, thereby ensuring that no alkaline components are lost through the gas stream 33 delivered to the customer.

[0037] The pure water supply line 10 is arranged to deliver pure water through pipes into the water supply container 9 to supplement the water consumption in the electrolysis system. The water is treated to dehydrate it from non-aqueous substances such as calcium and other contaminants, as such contaminants can accumulate in the system. Since the water supply container 9 is directly connected to the atmosphere via a coaxially arranged outlet pipe 16, the pure water supply source 10 can operate at a pressure only slightly above atmospheric pressure, for example, 1 bar above atmospheric pressure, and still remain protected against the possibility of backflow of alkaline-containing water from the water supply container 9.

[0038] However, any blown material flows 11, 31 arriving from the safety valve or depressurization process may reach or even exceed the system pressure in the pressurized stack, separator container, and gas handling system, and therefore the feedwater container 9 should ideally be sized to withstand such high pressures.

[0039] Figures 2 and 3 show the upper part of the water supply container 9, which, as seen, has an inner cylindrical surface 14. A pipe stub indicates the access point for material flows 11, 31 directed into the container 9, and the pipe stub has an inclined outlet opening intended to give the material flows a tangential inflow direction to the cylindrical surface 14. This is intended to generate a vortex or cyclone material flow along the cylindrical surface 14. Figure 4 shows a somewhat elaborate tangential inflow of material flow 11 into the cylindrical part of the water supply container. This design is likely to cause more particles and fluid to settle on the inner cylindrical surface of the container 9. The desired cyclone effect is enhanced in both cases by an outlet pipe 16, which is positioned such that its central axis 17 is coaxial with the cylindrical axes of the cylindrical parts 14, 15 within the container 9. Preferably, the outlet pipe extends downward within the container 9 to a point somewhat lower than the inlet point of the material flow 11, but has a lower edge that is higher than the water level in the water supply container 9.

[0040] In Figure 6, the cylindrical surface 15 is schematically shown as an insert element within the container 9, and as seen in the figure, the insert has a tapering, downward-facing conical portion 30 that ends at a cyclone outlet 29 into the water supply container 9. The conical portion or cyclone surface 30 causes the material flow 11 tangentially directed onto the cylindrical surface 15 to rotate while increasing in velocity toward the outlet 29. This promotes the sedimentation of material portions having a higher density than the gas phase in the material flows 11, 31. The outlet pipe 16 is positioned coaxially with the cylindrical surface 15 and, in this embodiment, does not need to be aligned with the longitudinal axis of the water supply container 9. Preferably, the pipe 16 has a lowest extension that is somewhat above the outlet opening 29 of the conical cyclone reinforcement surface 30. An advantage of this embodiment is that obstacles to the rotation of the material flow 11, 31 on the inner surface of the water supply container 9, such as inspection openings or further inlets into the container, do not obstruct the cyclone flow along the cyclone surface 30 and / or cylindrical portion 15 inside the water supply container 9.

[0041] A safety valve 12 is schematically disclosed in Figure 8. Also shown is a main pump 34 capable of driving the alkaline electrolyte flow 26 and the hydrogen-generating gas and electrolyte flow 28 to and from the array of stack 2. A heat exchanger 35 is inserted into the electrolyte flow between separators 24, 23 and stack 2 to ensure that the stack receives the electrolyte at a constant temperature.

[0042] A water supply pressure pump 19 is shown in Figures 8 and 5, and this pump is adapted to raise the water supply pressure from the water supply container to the system pressure, so that this water can flow into the washing container 21 at the system pressure.

[0043] Currently, alkaline water electrolysis cells are operated at pressures between 30 and 40 bar. However, systems operating at pressures up to 120 bar are expected to be used in the future.

[0044] It should be noted that the drawings and the above description provide a simple and schematic representation of exemplary embodiments. Many of the specific mechanical details are not shown because those skilled in the art should be familiar with them, and these details would only unnecessarily complicate this description. [Explanation of Symbols]

[0045] 1. Alkaline water electrolysis system 2 Electrolytic cell stack 3 Diaphragm 4 Half Cells / Oxygen-Generating Half Cells 5 Half Cells / Hydrogen-Generating Half Cells 6. Oxygen-generating gas flow 7. Hydrogen-generating gas flow 8. Fluid drain effluent 9. Water container 10 Pure water source 11. Discharge material flow 12 Safety valve 13. Water flow with increased alkalinity 14. Cylindrical section inside the water tank 15 Inner cylindrical surface 16 Coaxially arranged outlet pipes 17. Central axis of the cylindrical part inside the water tank 18. Excessive gas flow 19. Water supply pressure pump 20. Water supply material flow and outlet pipes 21 Gas washing container 22 (Single cell in a cell stack) 23. Oxygen gas separator 24 Hydrogen gas separator 25. Oxygen-depleted electrolyte flow 26 Hydrogen-depleted electrolyte flow 27. Oxygen-producing gas and electrolyte mixture 28. Hydrogen-producing gases and electrolyte mixtures 29 Cyclone Exit 30 Cyclone surface 31 Gas washing container reduced pressure flow 32 Further gas regulators 33 Gas delivery 34 Main pump

Claims

1. A method for preparing feedwater for an alkaline water electrolysis system (1), wherein the alkaline water electrolysis system (1) comprises one or more electrolytic cell stacks (2), and each stack (2) has at least one diaphragm (3) that separates oxygen-generating half cells (4) from hydrogen-generating half cells (5), thereby all oxygen-generating half cells (4) deliver an oxygen-electrolyte mixture (27), and all hydrogen-generating half cells (5) deliver a hydrogen-electrolyte mixture (28), thereby each of the mixtures being piped to their respective separators (23, 24), where mainly an oxygen-generating gas stream (6) and an oxygen-depleted electrolyte stream (25), and A water supply preparation method characterized in that the system (1) is separated into a hydrogen-generating gas stream (7) and an electrolyte stream (26) from which hydrogen has been depleted, thereby replenishing the electrolyte streams (25, 26) with water from a water supply container (9), the alkaline water electrolysis system (1) further comprises a generated gas adjustment system, the water supply container (9) receives a discharge material stream (11) from at least one safety valve (12) when the valve (12) is activated, and / or receives a discharge material stream (31) from the depressurization of the pressurized gas cleaning container (21) of the generated gas adjustment system, and the gas cleaning container (21) holds the generated gas (7) when the depressurization of the system (1) is initiated.

2. The water supply preparation method according to claim 1, wherein the discharge material flow (11, 31) is directed tangentially onto the inner cylindrical surfaces (14, 15) inside the water supply container (9) to form a cyclone, thereby causing any possible solids and liquids to settle on the inner cylindrical surfaces (14, 15) and gases to exit the container (9) along an outlet pipe (16) which is arranged coaxially with the central axis (17) of the inner cylindrical surfaces (15, 14).

3. The water supply container (9) receives alkali-containing fluid drain effluent (8) resulting from a filtration and drying process performed on each of the generated gas flows (6, 7), according to claim 1 or 2.

4. A method for preparing feedwater according to any one of claims 1 to 3, wherein the feedwater from the feedwater container and any alkaline material potentially dissolved therein are pressurized and used in a generated gas washing process in a gas washing container (21), and any alkaline substances that may be carried in the generated gas stream (6, 7) are dissolved in the pressurized feedwater, and the water (13), which has thus become even more alkaline, flows into one of the separators (23, 24) to replenish the water lost during the electrolysis process in the half-cells (5, 6).

5. A water supply preparation method according to any one of claims 1 to 4, wherein a first water supply container (9) receives fluid and gas from a hydrogen preparation system and delivers water supply to a hydrogen gas cleaning process, and a second water supply container receives fluid and gas from an oxygen preparation system and delivers water supply to an oxygen gas cleaning process.

6. A water supply preparation system within an alkaline water electrolysis system (1), wherein the alkaline water electrolysis system (1) is configured to produce hydrogen and oxygen in one or more pressurized electrolytic cell stacks (2), and each stack (2) has at least one diaphragm (3) that separates oxygen-producing half cells (4) from hydrogen-producing half cells (5), thereby configured that all oxygen-producing half cells (4) deliver an oxygen-electrolyte mixture (27), and all hydrogen-producing half cells (5) deliver a hydrogen-electrolyte mixture (28), thereby separating each of the mixtures from their respective separators A water supply preparation system characterized in that the alkaline water electrolysis system (1) is further equipped with a gas production system, a safety valve blowout material flow pipe (11) connected to the water supply container (9), and / or a reduced pressure flow pipe (31) from the gas cleaning container (21) of the gas production system connected to the water supply container (9). The system is characterized in that the material is sent via pipes to a regulator (23, 24), where it is separated into a gas production flow (6) mainly composed of oxygen and an electrolyte flow (25) depleted of oxygen, and a gas production flow (7) mainly composed of hydrogen and an electrolyte flow (26) depleted of hydrogen, thereby replenishing the electrolyte flows (25, 26) with water from a water supply container (9), and the alkaline water electrolysis system (1) is further equipped with a gas production system, a safety valve blowout material flow pipe (11) connected to the water supply container (9), and / or a reduced pressure flow pipe (31) from the gas cleaning container (21) of the gas production system connected to the water supply container (9).

7. The water supply preparation system according to claim 6, wherein the safety valve pipe and material flow (11) and / or pressure reducing flow pipe (31) are connected tangentially to the cylindrical portion (14, 15) inside the water supply container (9) to discharge the material flow (11) along the inner cylindrical surface portion (14, 15) inside the water supply container (9), and further, the outlet pipe (16) is provided coaxially with the cylindrical axis of the inner cylindrical surface portion (14, 15) inside the water supply container (9) and is directly connected to the atmosphere.

8. The water supply container (9) is connected to a drain (8) from a further gas regulator (32) in the gas adjustment system (21, 23, 24, 32), according to claim 6 or 7.

9. A water supply outlet pipe (20) from the bottom of the water supply container (9) is connected to a water supply pressure pump (19) and is adapted to supply a water supply material flow (20) into a gas scrubbing container (21), and the pipe further interconnects the gas scrubbing container (21) and a gas separator (24), thereby allowing water from the water supply container (9) to be sent through the pipe via the gas scrubbing device (21) and flow into the gas separator (24) as an alkaline water flow (13), thereby replenishing the water lost in the water electrolysis process, according to any one of claims 6 to 8.

10. A water supply preparation system according to any one of claims 6 to 9, wherein a first water supply container (9) is connected to the drain and filter of a hydrogen gas preparation system (32) and further connected to a hydrogen gas cleaning container (21) to supply water thereto, and a second water supply container is connected to the drain and filter of an oxygen gas preparation system and further connected to an oxygen gas cleaning container to supply water thereto.

Images