Apparatus and method for purification of electrolyte solutions for hydrogen production via electrolysis

Abstract

Equipment and methods for electrolyte purification can be configured to remove iron from a solution, thereby purifying the electrolyte solution for feeding into one or more electrolyzers for the production of hydrogen from water via electrolysis. Examples may utilize a reactor with an iron removal agent positioned inside, allowing the electrolyte solution to pass through the reactor's container to remove iron. Other embodiments may include adding an iron removal agent to a tank, stirring it with water and an electrolyte material (e.g., KOH material) to form the electrolyte solution, and subsequently filtering out iron-containing materials included in the formed solution via the iron removal agent. Examples may be configured to provide an electrolyte solution with a pre-selected iron concentration to help prevent scaling of electrodes used in the electrolytic process.

Description

[0001] Cross-references to related applications This application claims priority to U.S. Provisional Application No. 63 / 669,000, filed July 9, 2024, and U.S. Non-Provisional Application No. 18 / 409,971, filed January 11, 2024. The entire contents of both applications are incorporated herein by reference. Technical Field

[0002] This innovation relates to a method and apparatus for purifying an electrolyte fluid used to produce hydrogen via electrolysis. Background Technology

[0003] Hydrogen can be produced via the electrolysis of water. Examples of systems configured to facilitate the production of hydrogen via electrolysis are disclosed in U.S. Patent No. 11,929,613 and U.S. Patent Application Publications Nos. 2022 / 0033983 and 2024 / 0141524. Summary of the Invention

[0004] Alkaline electrolyzers that produce hydrogen via electrolysis can rely on concentrated aqueous hydroxide solutions as the conductive electrolyte. We have determined that the optimal performance of an electrolyzer cell depends on maintaining high conductivity in the electrolyte, through the separator, and at the electrode-electrolyte interface of the electrolyzer. Trace impurities, including transition metals and organic impurities, can lead to increased resistance at the electrode interface and within the electrolyte, which can degrade the electrolyzer's performance.

[0005] Compared to proton exchange membrane electrolysis (PEMWE), alkaline water electrolysis (AWE) for hydrogen production relies on a concentrated hydroxide solution as the conductive electrolyte. Hydroxide ion conductivity can be achieved using an aqueous solution of potassium hydroxide (KOH) at a concentration of approximately 30 wt%, although other concentration ranges are alternatively used for alkaline water electrolysis (AWE) (e.g., 0.5 wt% KOH to 50 wt% KOH, between 15 wt% KOH and 25 wt% KOH, and between 25 wt% KOH and 35 wt% KOH). We have found that KOH and common impurities in water increase the resistance of the electrolyzer in several ways. For example, reducible transition metal impurities can deposit on the surfaces of electrodes and electrocatalysts, thereby altering and, in many cases increasing, the cell overpotential. In fact, we have found that when iron(II) cations (Fe... 2+ ) and iron(III) cations (Fe 3+Maintaining iron levels at very low levels can provide long-term stable operation of the electrolyzer. Examples of such low iron levels in the electrolyte solution can be iron content thresholds between 0 ppb and 400 ppb, 0 ppb and 200 ppb, 100 ppb and 0 ppb, or 50 ppm and 0 ppb. For example, some embodiments may utilize iron content thresholds of no more than 100 ppb or no more than 50 ppb for the electrolyte solution used in AWE electrolyzers.

[0006] We have found that using a pre-selected iron concentration threshold can help ensure that a purified electrolyte solution can be formed and fed into the electrolyzer, thus helping to maintain electrolyzer life and avoid electrode scaling, or at least help to significantly minimize such corrosion or scaling. And we have surprisingly found that this type of problem can be substantial for industrial applications that may utilize a large number of electrolyzer units to produce hydrogen on a large scale via electrolysis.

[0007] For example, in gigawatt (GW) scale electrolysis units, the accumulation of impurities in the electrolyte can be substantial, potentially necessitating the replacement of thousands of metric tons (MT) of caustic electrolyte cells. This can represent significant material costs and logistical challenges. For instance, handling such large quantities of KOH solution can have a significant environmental impact, and the cost of replacing the solution can be substantial in terms of material costs and operational downtime for replacement, while also reducing production flexibility.

[0008] We have found that purifying the electrolyte solution can reduce the levels of some or all significant impurities to help delay or prevent scaling, thereby extending the electrolyte solution's operational life. This can help reduce operational downtime and costs associated with electrolyte solution changes and refurbishment or electrode replacement. We have found that proper purification of the electrolyte solution at the beginning of its supply and use can help prevent premature damage to the electrolyzer and protect the lifespan of those units. We have also surprisingly found that focusing on a pre-selected iron concentration threshold to help control purification can help ensure proper purification, thereby protecting electrolyzer life and helping to limit or prevent electrode scaling and / or corrosion.

[0009] For example, purification that leads to the reduction of iron in the electrolyte solution can also promote the removal of other transition metals, inorganic anions such as sulfate and carbonate, and organic impurities such as phthalates and their basic phthalate hydrolysis products, phenolic components, and trace amounts of humic organic materials. Other impurities are also removed, and the selected iron concentration threshold can help promote the removal of these other impurities and significant amounts of iron, while ensuring that the iron impurity content in the electrolyte solution is at or below the threshold (e.g., 500 ppb, 200 ppb, 100 ppb, 50 ppb, etc.).

[0010] While focusing on removing iron from the electrolyte solution to purify the solution can facilitate the removal of carbonate and / or sulfate impurities, we have found that a reduction in the amount of dissolved iron can help ensure that organic compounds are also removed. It is anticipated that in some embodiments, organic compound impurities may also be reduced to acceptable levels in electrolyte solutions (e.g., KOH electrolyte solutions, etc.) that are formed as hydroxide solutions.

[0011] The embodiments may be adapted to help provide a relatively rapid method for purifying electrolyte solutions. Furthermore, some embodiments may provide a portable purification system, allowing the purification system to be removably coupled to different production units for different electrolyte purification methods, which can support multiple different industrial processing locations in geographically spaced areas (e.g., at different facilities located in different states or countries). Other embodiments may alternatively provide a site-specific system for purifying electrolyte solutions.

[0012] In a first aspect, a method for purifying an electrolyte can be provided. Embodiments of the method may include purifying an electrolyte solution such that the iron (Fe) content of the electrolyte solution is at or below a pre-selected Fe concentration threshold. In some embodiments, the pre-selected Fe concentration threshold may be between 0 ppb Fe and 500 ppb Fe. Purifying the electrolyte solution may include passing the electrolyte solution through a reactor to contact purification material within the reactor chamber, thereby removing impurities and / or filtering the electrolyte solution to remove impurities from the electrolyte solution. The method may also include feeding the purified electrolyte solution into a storage tank or one or more electrolyzers.

[0013] In some embodiments, the pre-selected Fe concentration threshold may be between 0 ppb F3 and 200 ppb Fe or between 100 ppb and 200 ppb Fe. In other embodiments, the pre-selected Fe concentration may be another pre-selected threshold (e.g., no more than 50 ppb Fe, no more than 150 ppb Fe, etc.).

[0014] In a second aspect, purifying the electrolyte solution may include passing the electrolyte solution through a reactor to contact purification material within the reactor chamber to remove impurities. The purification material within the reactor chamber may include at least one impurity remover. In some embodiments, the at least one impurity remover may be coated onto a particulate carrier. In other embodiments, the purification material may include solid particles comprising at least one impurity remover. In some embodiments, the impurity remover may include magnesium oxide (MgO) and / or magnesium hydroxide (Mg(OH)2).

[0015] In a third aspect, purifying the electrolyte solution may further include filtering the electrolyte solution to remove impurities from it. Filtration may be performed without passing the electrolyte solution through the reactor, or it may be performed as a supplement to passing the electrolyte solution through the reactor. In some embodiments, for example, filtration may be performed via at least one filter element or filter mechanism positioned in the reactor near an outlet in fluid communication with a chamber of the reactor.

[0016] In a fourth aspect, the method may include additional steps. For example, the method may include forming an electrolyte solution by mixing an electrolyte material with water and at least one purified material in a mixing tank. In some embodiments, purifying the electrolyte solution may include filtering the electrolyte solution to remove the purified material from the electrolyte solution, thereby removing impurities from the electrolyte solution after the electrolyte material has been mixed with water. For example, in some embodiments, the method may include feeding the electrolyte solution from the mixing tank to at least one filtration system for filtering the electrolyte solution to remove the purified material from the electrolyte solution, thereby removing impurities from the electrolyte solution. The electrolyte solution purified via the at least one filtration system may then be fed into a storage tank that may be fluidly connected to at least one electrolyzer.

[0017] In a fifth aspect, the method may include feeding an electrolyte solution purified by purifying the electrolyte solution into a storage tank. The storage tank may be fluidly connected to at least one electrolyzer. The electrolyte solution may then be fed into the electrolyzer via the storage tank. Alternatively, the electrolyte solution may be fed into the electrolyzer without intermediate storage in such a storage tank.

[0018] In a sixth aspect, the method can be used in conjunction with a purification system that can be configured as a portable purification system. For example, the method may include, after feeding the purified electrolyte solution into a storage tank, separating the portable purification system from the storage tank, and moving the portable purification system to another location to purify the electrolyte solution at that location, or moving the portable purification system to another storage tank to purify the electrolyte solution stored therein. In some embodiments, the portable purification unit may include a portable reactor and / or a portable filtration system.

[0019] In the seventh aspect, the method of the first aspect may include one or more features of the second, third, fourth, fifth, and / or sixth aspects. Embodiments of the method may also include other method steps or elements. Examples of such other features or method steps may be understood from the discussion of exemplary embodiments of the methods discussed herein.

[0020] Embodiments of this method can be implemented in exemplary embodiments of an apparatus for purifying electrolyte solutions. Such an apparatus may include conduits, valves, and / or process control systems to facilitate the operation of the apparatus and / or the implementation of the method embodiments.

[0021] In an eighth aspect, an apparatus for purifying an electrolyte solution is provided. The apparatus may include a reactor having a chamber that holds a purified material within the chamber. The purified material may be configured to remove impurities from the electrolyte solution to reduce the iron (Fe) content of the electrolyte solution, thereby forming a purified electrolyte solution with an Fe content equal to or less than a pre-selected Fe content threshold between 0 ppb Fe and 500 ppb Fe.

[0022] The device may also include a reactor inlet conduit connected to the reactor inlet. The reactor inlet conduit can be connected to a source of electrolyte solution or a storage tank in which the electrolyte solution can be retained.

[0023] The apparatus may also include a reactor outlet conduit connected to the reactor outlet. The reactor outlet conduit may be connected to a storage tank and / or an electrolyzer feed conduit to feed purified electrolyte solution from the reactor outlet to the storage tank and / or at least one electrolyzer.

[0024] In some embodiments, the purification material includes magnesium oxide (MgO) and / or magnesium hydroxide (Mg(OH)2). For example, in some embodiments, the purification material may include MgO and / or Mg(OH)2 as a coating on a carrier and / or in solid particles, which may be positioned in the chamber of the reactor for contact with the electrolyte solution, thereby removing Fe and other impurities from the electrolyte solution.

[0025] In other embodiments, the purification material may include other types of impurity removers that can remove Fe and / or other impurities.

[0026] Embodiments of this device can be configured to implement methods for purifying electrolyte solutions.

[0027] In a ninth aspect, the apparatus also includes a pump connected to a reactor inlet conduit and a movable base supporting the pump, the reactor inlet conduit, the reactor outlet conduit, and the reactor. In some embodiments, the movable base may be a movable rail, a movable trailer, or other type of movable support that can be moved by railcar, truck, forklift, or other type of vehicle.

[0028] In a tenth aspect, the apparatus may include a storage tank. The outlet conduit of the storage tank may be connected to a pump to feed the electrolyte solution from the storage tank to the reactor inlet conduit.

[0029] In an eleventh aspect, the apparatus may include an electrolyzer feed conduit. The electrolyzer feed conduit may be connected to a reactor outlet conduit to connect reactor fluid to at least one electrolyzer, thereby feeding a purified electrolyte solution that can be output from the reactor into at least one electrolyzer.

[0030] In the twelfth aspect, the device of the eighth aspect may include one or more features of the ninth, tenth, and / or eleventh aspects. Embodiments may also include other features or elements. Examples of such features or elements can be understood, for instance, from the discussion of exemplary embodiments of the device provided herein.

[0031] In a thirteenth aspect, the apparatus for purifying an electrolyte solution may include a mixing tank fluidly connected to a source of water, a source of electrolyte material, and a source of purified material to receive water, electrolyte material, and purified material for mixing therein to form an electrolyte solution. A filtration system may be connected to the mixing tank to receive the electrolyte solution from the mixing tank and remove particles of purified material from the electrolyte solution, thereby outputting a purified electrolyte solution having an iron content less than or equal to a pre-selected iron (Fe) content threshold, the pre-selected iron content threshold being between 0 ppb Fe and 500 ppb Fe. Embodiments of this apparatus may be configured to implement embodiments of a method for purifying an electrolyte solution.

[0032] Embodiments of the device may also include other features or elements. For example, the device may also include a tank located downstream of the filtration system to receive a purified electrolyte solution output from the filtration system and / or at least one electrolyzer fluidly connected to the tank to receive the purified electrolyte solution from the tank.

[0033] As described above, in some embodiments, the purification material includes magnesium oxide (MgO) and / or magnesium hydroxide (Mg(OH)2). For example, in some embodiments, the purification material may include MgO and / or Mg(OH)2 as a coating on a carrier and / or in solid particles, which may be positioned in a mixing vessel for contact with other components of the electrolyte solution to be formed, thereby removing Fe and other impurities from the electrolyte solution by subsequently filtering the purification material from the formed electrolyte solution. In other embodiments, the purification material may include other types of impurity removers capable of removing Fe and / or other impurities.

[0034] It should be recognized that embodiments of the methods and apparatus can utilize a variety of conduit arrangements and process control elements. Embodiments may utilize sensors (e.g., pressure sensors, temperature sensors, flow rate sensors, concentration sensors, etc.), controllers, valves, piping, and other process control elements. Some embodiments may utilize, for example, automated process control systems and / or distributed control systems (DCS). A wide variety of conduit arrangements and process control systems can be used to meet a specific set of design criteria.

[0035] Further details, objectives, and advantages of the apparatus for purifying electrolyte solutions, the methods for purifying electrolyte solutions, the systems for providing electrolyte solutions for generating hydrogen via electrolysis, and the methods for their manufacture and use will become apparent from the following description of certain exemplary embodiments thereof. Attached Figure Description

[0036] The accompanying drawings illustrate exemplary embodiments of our apparatus for purifying electrolyte solutions, methods for purifying electrolyte solutions, systems for providing electrolyte solutions for generating hydrogen via electrolysis, and methods for manufacturing and using these solutions. It should be understood that the same reference numerals used in the drawings may identify the same parts.

[0037] Figure 1 This is a block diagram of a first exemplary embodiment of an apparatus for purifying electrolyte solutions. An exemplary embodiment of a method for purifying electrolyte solutions is also shown in the figure.

[0038] Figure 2 This is a block diagram of a first exemplary embodiment of a device for purifying electrolyte solutions. An exemplary embodiment of a method for purifying electrolyte solutions is also shown in the figure.

[0039] Figure 3 This is a block diagram of a second exemplary embodiment of a first exemplary embodiment of an apparatus for purifying electrolyte solutions. An exemplary embodiment of a method for purifying electrolyte solutions is also shown in the figure.

[0040] Figure 4This is a block diagram of a third exemplary embodiment of a first exemplary embodiment of an apparatus for purifying electrolyte solutions. An exemplary embodiment of a method for purifying electrolyte solutions is also shown in the figure.

[0041] Figure 5 This is a block diagram of a fourth exemplary embodiment of a first exemplary embodiment of an apparatus for purifying electrolyte solutions. An exemplary embodiment of a method for purifying electrolyte solutions is also shown in the figure.

[0042] Figure 6 It is possible Figures 1 to 5 A schematic diagram of a first exemplary embodiment of the apparatus for purifying electrolyte solutions, using reactor 5.

[0043] Figure 7 It is possible Figures 1 to 5 A schematic diagram of a second exemplary embodiment of the reactor 5 used in an embodiment of the apparatus for purifying electrolyte solutions.

[0044] Figure 8 This is a schematic diagram of an exemplary embodiment of the purification material 5m that can be included in an exemplary embodiment of reactor 5.

[0045] Figure 9 This is a schematic diagram of another exemplary embodiment of the purification material 5m that may be included in the exemplary embodiment of reactor 5.

[0046] Figure 10 This is a flowchart illustrating an exemplary embodiment of a method for purifying electrolyte solutions. Embodiments of the apparatus for purifying electrolyte solutions can implement exemplary embodiments of this method. Detailed Implementation

[0047] refer to Figures 1 to 10An apparatus 1 for purifying an electrolyte solution can be provided, such that the purified electrolyte solution can be fed into one or more electrolyzers E and / or a storage tank 3, which is positioned to supply the electrolyte solution to at least one tank of one or more electrolyzers. The apparatus may include a purification unit 4, which can be positioned to feed an electrolyte solution from a source of electrolyte solution ES to the purification unit for purification. The electrolyte solution may include a pre-selected electrolyte concentration. For example, the electrolyte solution may have a pre-selected electrolyte material concentration between 0.5 wt% and 50 wt% electrolyte (e.g., between 0.5 wt% KOH and 50 wt% KOH, between 15 wt% KOH and 25 wt% KOH, between 25 wt% KOH and 35 wt% KOH, etc.). The purification unit 4 may be positioned to receive an electrolyte solution from a source of electrolyte solution ES or from a storage tank 3, which may receive an electrolyte solution from a source of electrolyte solution ES for retaining the fluid therein for subsequent supply to one or more electrolyzers E.

[0048] Storage tank 3 may include a tank, container array, or other type of storage device for storing an electrolyte solution to feed into one or more electrolyzers E. Each electrolyzer E may be an alkaline water electrolysis (AWE) electrolyzer or other suitable type of electrolyzer. Electrolyzer E may be powered by a renewable energy source to produce green hydrogen via water electrolysis. For example, a power source that generates electricity from a renewable source (e.g., solar, wind, hydropower, etc.). In some embodiments, device 1 may be incorporated into a plant for producing hydrogen and / or a plant that can produce hydrogen for subsequent use in ammonia production. In embodiments configured for ammonia production facilities, an air separation unit may also be present, positioned to form nitrogen gas, so that hydrogen and nitrogen from electrolyzer E can be used to form ammonia.

[0049] The source of the electrolyte solution ES can be a batch of electrolyte solutions, which may include electrolyte solutions stored in at least one container or tank provided by a supplier. Alternatively, the source of the electrolyte solution ES may include a mixing tank 13, which may be formed from water (e.g., high-purity water), potassium hydroxide (KOH), and / or other materials combined in the mixing tank to form the electrolyte solution. The source of the electrolyte solution ES may also include a combination of such sources. The electrolyte solution may include KOH as the primary electrolyte component. Other embodiments may utilize other types of hydroxide salts or other types of electrolytic electrolyte compounds for forming the electrolyte solution.

[0050] Purification unit 4 may include reactor 5, which may be configured to include purification material 5m, which is used to contact and fluidly interact with the electrolyte solution to remove impurities from the electrolyte solution to purify the solution. Purification material 5m may be an impurity remover, reagent material, adsorbent material, absorbent material, or other type of purification material 5m.

[0051] For example, in some embodiments, a purifying material 5m, which may be positioned in the chamber 5c of the reactor for contacting the electrolyte solution to purify it, may include magnesium oxide (e.g., MgO) and / or magnesium hydroxide (e.g., Mg(OH)2). The purifying material 5m may be a coating on a carrier, may be in particulate form 5p (e.g., in the form of small spheres of a specific size, etc.), or may be provided in small particulate form as a compressed particulate filter cake 5 in different embodiments. In some embodiments, the particle size of the purifying material may be set between 0.2 micrometers and 3 micrometers to be provided in the filter cake 5. In some embodiments, the particle size of the purifying material 5m, which may be used as an impurity removal material within the chamber 5c of the reactor, may be between 0.1 millimeters (mm) and 3 mm. The size, shape, and structure of the particulate purifying material 5m may include voids, a solid-shaped structure, or other shapes or geometries to facilitate desired levels of contact and residence time with the electrolyte solution passing through the chamber 5c of the reactor 5, thereby contacting the purifying material 5 to remove impurities (e.g., Fe) and purify the electrolyte solution.

[0052] Purification unit 4 may alternatively include at least one filtration device of filtration system FS, which can filter out precipitates containing impurities that may have already formed in the electrolyte solution and / or other solid particles in the electrolyte solution that may contain or include impurities, in order to purify the electrolyte solution. Some embodiments may also utilize a purification unit 4 for purifying the electrolyte solution, which includes a combination of at least one filtration system FS and at least one reactor 5.

[0053] Examples may be provided such that the electrolyte solution passing through purification unit 4 may have a residence time within reactor 5 of no more than 30 minutes, no more than 1 hour, or within another pre-selected purification time range (e.g., a time range greater than 0 seconds and less than or equal to 2 hours, a time range greater than 0 seconds and less than or equal to 1 hour, or a time range greater than 0 seconds and less than or equal to 30 minutes, a time range greater than 0 seconds and less than or equal to 5 minutes, a time range greater than 0 seconds and less than or equal to 30 seconds, etc.). For example, the electrolyte solution may be fed into reactor 5 via reactor feed conduit 5i. The feed electrolyte solution may include impurities higher than a pre-selected impurity standard. For example, the electrolyte solution fed into the reactor for purification may have an iron concentration of more than 500 ppb, at least 600 ppb, more than 800 ppb, more than 1,000 ppb, or other high impurity concentrations.

[0054] Reactor 5 can purify the electrolyte solution, such that the purified electrolyte solution can be output from reactor 5 as a purified electrolyte solution output stream, which can pass through reactor output conduit 5o into at least one electrolyzer E or storage tank 3. The purified electrolyte solution may have an impurity content within a pre-selected impurity content threshold range or a pre-selected impurity content standard. Such a standard or content threshold range may include, for example, a pre-selected iron content at or below a pre-selected iron content threshold. The pre-selected iron content threshold may be, for example, between 0 ppb iron (Fe) and 50 ppb Fe, between 0 ppb Fe and 100 ppb Fe, between 0 ppb iron (Fe) and 200 ppb Fe, between 0 ppb Fe and 400 ppb Fe, between 0 ppb Fe and 500 ppb Fe, or other desired ranges. It has been found that utilizing a pre-selected iron content threshold also provides an alternative to delivering the desired low levels of other impurities, such as transition metal impurities and organic impurities (e.g., phthalates and their basic phthalate hydrolysis products, phenolic components, trace amounts of humic organic materials, etc.). Purification of the electrolyte solution can result in lower levels of impurities in the electrolyte solution output from reactor 5 (e.g., the electrolyte solution fed into the reactor may have a higher impurity content than the purified electrolyte solution output from reactor 5).

[0055] In some embodiments, at least a portion of the purified electrolyte solution can be output from reactor 5, as the purified electrolyte solution output stream can be recycled back to reactor 5 via recirculation conduit R for further purification. Recirculation of the electrolyte solution back to reactor 5 can help ensure that the purified electrolyte solution has sufficient residence time to provide the desired level of purification of the electrolyte solution ultimately output from reactor 5 for use in one or more electrolyzers.

[0056] In some embodiments, the purification unit 4 may be movable and modular for removable fluid connection to a source or storage tank 3 of the electrolyte solution ES. When coupled to one or more such elements, the purification unit can receive the electrolyte solution for purification. After purification has been performed and the purified electrolyte solution has been fed to an electrolyzer at a specific geographic location, the movable purification unit 4 can be detached from the element at that location and moved to a new geographic location away from its previously used location. Once at the new location, the purification unit can be removably connected to a source or storage tank 3 of the electrolyte solution ES at the new location to purify the electrolyte solution there.

[0057] In other cases, after being used in conjunction with a first storage tank 3 at a specific location, the portable purification unit 4 can be detached from the components at the initial storage tank 3 and moved to a second storage tank 3 at the same location for subsequent use at that location. After the electrolyte solutions of the storage tanks throughout the location have been purified, the portable purification unit 4 can then be moved to a new geographical location, to another plant at another location, for subsequent use at the new location.

[0058] Typically, electrolyte solution purification may only need to be performed once every 2-3 years or intermittently at any particular location. In other cases, the electrolyte solution may only need to be purified in the initial time before it is fed into the electrolyzer, and may not require any further treatment when the solution is used during the operation of the electrolyzer. The mobile purification unit 4 can provide improved flexibility by allowing a single asset to be moved to different locations (or different sources or tanks) for use at different times, so that the capital costs associated with the asset can be allocated more efficiently and flexibly to support many different remote production facilities. In some embodiments, the mobile purification unit can be positioned on a trailer or rail so that the purification unit can be transported via trucks, railcars and / or other vehicles for removable connection to different units at different locations. Removable fluid connections can be provided via valves, mechanical fasteners or other removable connection mechanisms for removably connecting reactor inlet conduits and reactor outlet conduits to tank 3, electrolyzer feed conduits or other conduit arrangements so that purification unit 4 can receive electrolyte fluid, purify it, and subsequently output the purified fluid to at least one tank 3 and / or at least one electrolyzer E. In some embodiments, for example, the output purified electrolyte solution can be fed into a different storage tank for storing the purified solution, the storage tank being fluidly connected to the electrolyzer E.

[0059] Furthermore, the embodiments can be used to purify both waste electrolyte solutions and fresh electrolyte solutions. For example, the embodiments can be configured such that during electrolyzer shutdown, the waste solution can be discharged into a storage tank and subsequently purified via purification unit 4 before being fed back to the electrolyzer or storage tank for subsequent feeding back to the electrolyzer. In some embodiments, the purification unit may be connected to one or more discharge lines between the electrolyzer and the storage tank for this treatment.

[0060] Figures 2 to 5 It shows Figure 1 Different exemplary embodiments of the device 1 shown herein are illustrated to demonstrate that it can be implemented in various ways. Figure 1 The different types of arrangements used in the exemplary embodiment of device 1 shown in the figure.

[0061] refer to Figure 2The electrolyte solution stored in tank 3 can be discharged from tank 3 via output conduit 3o to feed to pump P. The stored electrolyte solution can be a fresh solution or a waste solution discharged from at least one electrolyzer E. The pump can output the electrolyte solution as a higher-pressure electrolyte solution stream 7 for feeding to reactor feed conduit 5i connected between tank 3 and reactor 5 and / or for feeding to electrolyzer E via electrolyzer feed conduit 9 connected between tank 3 and electrolyzer E, to feed the electrolyte solution into reactor 5 for purification of the electrolyte solution. Reactor feed conduit 5i may include a valve V adjustable between an open position and a closed position. In the closed position, fluid may not be passed into the reactor. In the open position, at least some of the electrolyte solution can be passed into reactor 5 via reactor feed conduit 5i.

[0062] For example, the electrolyzer feed conduit 9 may include a first valve V1 and a second valve V2 located upstream of the fourth valve V4. The tank inlet conduit 3i may also be connected between the pump P and the tank, such that when the first valve V1 and the fourth valve V4, or the second valve V2 and the fourth valve V4, are closed, the electrolyte solution can be returned to the tank 3. The tank inlet conduit may include a third valve V3, which is adjustable between an open and closed position to facilitate this flow of the electrolyte solution (e.g., the third valve V3 may be closed when the electrolyte solution is fed into the electrolyzer E and / or reactor 5, and may be opened to allow the electrolyte solution to return to the tank 3 when the feeding of solution into the electrolyzer E and / or reactor 5 is stopped).

[0063] In some embodiments, the second valve V2 may be a check valve. In other embodiments, the second valve V2 may be another type of valve.

[0064] When the fourth valve V4 is in the open or partially open position, reactor 5 can receive the electrolyte solution via reactor feed conduit 5i. The purification material 5m within reactor chamber 5c can contact the electrolyte solution flowing through reactor 5 as it passes through the reactor to its outlet. The reactor outlet is in fluid communication with reactor outlet conduit 5o. Figure 6 and Figure 7 As shown by arrow ESF. The purified electrolyte solution output from reactor 5 can pass through reactor output conduit 5o for feeding into electrolyzer feed conduit 9, and then into electrolyzer E. Reactor output conduit 5o may include a fifth valve V5, which can be in an open position to facilitate the feeding of the purified solution into electrolyzer E.

[0065] In some embodiments, the fifth valve V5 can be closed during purification, allowing the electrolyte solution passing through and exiting the reactor 5 to be recirculated back to the reactor 5 via a recirculation conduit arrangement R positioned between the reactor outlet conduit 5o and the reactor 5. Once the fluid has been sufficiently purified, the fifth valve V5 can be opened, allowing the fluid exiting the reactor 5 to be fed into the electrolyzer E via the outlet conduit 5o. Alternatively, this recirculation conduit may not be used, or the fifth valve V5 may be opened to feed some of the purified electrolyte solution into the electrolyzer, while another portion of the output fluid is recirculated back to the reactor via the recirculation conduit arrangement R.

[0066] The positions of the fourth valve V4, the fifth valve V5, and the first valve V1 can be adjusted to control the extent to which the electrolyte solution output from the storage tank 3 is fed into the electrolyzer E. In some configurations, all fluid can be fed into the reactor 5 and subsequently output from the reactor as a purified electrolyte solution for feeding into the electrolyzer E. In other cases, it may be necessary to purify only a portion of the electrolyte solution to control the impurity content of the solution, such that the solution fed into the electrolyzer is at or below a pre-selected impurity content. In this case, only a portion of the electrolyte solution can be purified, and the purified electrolyte solution output from the reactor can be mixed with the less purified electrolyte solution passing through the electrolyzer feed conduit 9. An online mixer or other type of mixing unit can be positioned in the electrolyzer feed conduit 9 to facilitate mixing of the purified electrolyte solution with the unpurified solution at the point where the purified electrolyte solution output from the reactor 5 is transferred to the electrolyzer feed conduit 9, or at a point downstream of the point where the purified electrolyte solution output from the reactor 5 is transferred via the output conduit 5o to the electrolyzer feed conduit 9.

[0067] refer to Figure 3 The purification unit 4 can alternatively be arranged to purify the electrolyte solution stored in the storage tank 3 and then feed the electrolyte solution to the electrolyzer E. The stored electrolyte solution can be a fresh solution or a waste solution discharged from at least one electrolyzer E.

[0068] For example, the reactor feed conduit 5i can be connected to the tank inlet conduit 3i, allowing the electrolyte solution output from pump P to be fed into reactor 5 while the first valve V1 and / or the second valve V2 are closed. The third valve V3 can also be in the closed position if the reactor feed conduit 5i is positioned upstream of the third valve V3 and the reactor outlet conduit 5o is positioned downstream of the third valve V3. This type of arrangement allows the electrolyte solution in tank 3 to pass through reactor 5 once or multiple times to purify the electrolyte solution via pump P. After the electrolyte solution has been sufficiently purified to a level equal to or below a pre-selected iron content threshold, the fourth valve V4 and the fifth valve V5 can be closed, and the electrolyte solution stored in tank 3 can be used to feed into one or more electrolyzers E via the electrolyzer feed conduit 9.

[0069] In some configurations or implementations, purification unit 4 may be arranged to purify a portion of the electrolyte solution stored in tank 3 before feeding it into electrolyzer E, while another portion of the electrolyte solution stored in the tank is fed into the electrolyzer without undergoing purification. This operation can be provided via partial opening of the first valve V1, the second valve V2, and the third valve V3. This type of configuration allows for the purification of only the portion of the electrolyte solution that may be needed, such that the electrolyte solution fed into electrolyzer E is at or below a pre-selected impurity content threshold (e.g., Fe content not exceeding 200 ppb, Fe content not exceeding 100 ppb, Fe content not exceeding 500 ppb, etc.).

[0070] like Figure 3 As shown by the dashed line, reactor 5, reactor feed conduit 5i, and reactor output conduit 5o can be positioned on a movable rail or other movable base, making these components part of a portable purification system MPS. The portable purification system MPS can be releasably connected to the tank inlet conduit 3i via a fourth valve V4 and a fifth valve V5 or other types of removable connection elements. After purification of the electrolyte solution has occurred, the portable purification system MPS can be detached from the tank inlet conduit 3i for relocation to a new location for purifying other electrolyte solutions stored in different tanks at the same facility as the first tank or at different facilities at different geographical locations.

[0071] Figure 4 Another exemplary embodiment is shown, wherein purification unit 4 is included in a portable purification system MPS. Figure 4 In an exemplary embodiment, the tank outlet conduit 3o may be a discharge conduit that is fluidly connected to the pump P of the mobile purification system MPS via a valve V and / or other releasable connection mechanism located between the reactor feed conduit 5i of the mobile purification system MPS and the tank outlet conduit 3o.

[0072] The pump P of the portable purification system can drive the electrolyte solution in tank 3 to flow to reactor 5 for purification via contact with purification material 5m. The purified electrolyte solution can be output from the reactor and fed into the storage tank feed conduit 3f. Valve V and / or other releasable connection mechanisms can be positioned between the reactor output conduit 5o and the storage tank feed conduit 3f of the portable purification system MPS to facilitate the flow of the purified electrolyte solution from reactor 5 to storage tank 3. The storage tank feed conduit may include valve V, which can be in an open position to receive the purified electrolyte solution output from reactor 5 for storage in the storage tank.

[0073] The tank feed conduit 3f can also be connected to the source of the electrolyte solution ES, allowing unpurified electrolyte solution from the source to be fed into the tank for storage.

[0074] After the electrolyte solution has been sufficiently purified by passing through reactor 5 of the portable purification system MPS once or multiple times, the electrolyte solution stored in tank 3 may be at or below a pre-selected impurity threshold (e.g., a pre-selected iron content threshold). The purified electrolyte solution in tank 3 can then be discharged from the tank via electrolyzer feed conduit 9 connected to tank 3. Electrolyzer feed pump P or other pump P can be activated to help drive the purified electrolyte solution from tank 3 through electrolyzer feed conduit 9 to electrolyzer E.

[0075] After the purification of the electrolyte solution has occurred, the portable purification system MPS can be detached from tank 3 for relocation to a new location to purify other electrolyte solutions stored in different tanks. These different tanks can be different tanks within the same facility or different tanks at different locations. This separation can be facilitated by disconnecting the pump P of the portable purification system MPS from the tank outlet conduit 3o (e.g., a discharge conduit) and the tank feed conduit 3f from the reactor outlet conduit 5o via valve V or other connecting mechanisms. Components of the portable purification system MPS (e.g., reactor 5, pump P, reactor outlet conduit 5o, reactor feed conduit 5i, etc.) can be positioned on a portable base (e.g., a rail, trailer, etc.) so that the portable purification system can be moved to a new location after separation. At the new location, the reactor outlet conduit 5o and pump P and / or reactor feed conduit 5i can be connected to tank 3 for purifying the electrolyte solution stored in that new tank at the new location.

[0076] refer to Figure 5Purification unit 4 may include a filtration system FS, which may include one or more filters for removing precipitates containing impurities. Mixing tank 13 may be a source of electrolyte solution, which may form the electrolyte solution via receiving a water feed from a water source 21 (e.g., a highly purified water source) and an electrolyte material feed from a source 23 of at least one electrolyte material. Electrolyte material 23 may also include one or more impurity removers (e.g., MgO, Mg(OH)2, etc.), which may be in particulate form and sized to adsorb iron and other impurities when a solution is formed by stirring, which may occur in the mixing tank as water is mixed with other components to form the electrolyte solution. In some embodiments, one or more impurity removers (e.g., MgO, Mg(OH)2, etc.) may be fed into the mixing tank via an impurity remover source that may be fluidly connected to the mixing tank 13, rather than these materials being included in the electrolyte material source 23.

[0077] After the solution is mixed for a pre-selected mixing time period to form an electrolyte solution, the formed electrolyte solution can be discharged from the mixing tank 13 via the mixing tank output conduit 13o connected between the mixing tank 13 and the filtration system FS. A pump P can be positioned in fluid connection to the mixing tank output conduit 13o to help drive the solution flow to the filtration system FS.

[0078] A filtration system FS may include one or more filters arranged in parallel or series to process an electrolyte solution to remove particulate material (e.g., MgO, Mg(OH)2, etc.) from the solution, thereby adsorbing impurities during the electrolyte solution formation process. Filtration of the particles can remove impurities to purify the electrolyte solution, such that the electrolyte solution has a content less than or equal to a pre-selected impurity threshold (e.g., less than or equal to a pre-selected iron content threshold, etc.).

[0079] The purified electrolyte solution can be output from the filtration system FS for feeding into the electrolyte storage tank 3 via the electrolyte storage tank inlet conduit 3f positioned between the filtration system FS and the storage tank 3. In some embodiments, the filtration system FS can be downstream of the pump P. In other embodiments, the filtration system FS can be upstream of the pump P.

[0080] The electrolyte solution fed into and stored in tank 3 can be at or below a pre-selected impurity threshold (e.g., a pre-selected iron content threshold). The purified electrolyte solution in tank 3 can then be discharged from the tank via an electrolyzer feed conduit 9 connected to tank 3 (e.g., via tank output conduit 3o and pump P, etc.). For example, the electrolyzer feed pump P can be activated to help drive the purified electrolyte solution from tank 3 through the electrolyzer feed conduit 9 to the electrolyzer E.

[0081] Figure 6 and Figure 7 Different exemplary reactor configurations of reactor 5 that can be utilized in purification unit 4 are shown. In some embodiments, purification material feed 6 may be fed into chamber 5c of the reactor to provide purification material for removing impurities from the electrolyte solution. Alternatively, the purification material may be positioned in chamber 5c before use and subsequently replaced as needed when reactor 5 is not used for purification processing. For example, purification material 5m may be positioned in chamber 5c of reactor 5 such that sufficient material is available for purifying the electrolyte solution for operations targeting solutions at specific locations, tank assemblies, etc.

[0082] After purification using reactor 5, the purified material 5m may need to be removed or replaced. This removal or replacement can be provided by opening the reactor to remove the purified material and replacing it, for example, with fresh purified material 5m.

[0083] The inlet and outlet regions of reactor 5 may include filtration elements to help retain the purified material 5m within the reactor chamber 5c. For example, a particle retention mechanism 5f (e.g., a mesh filter, filter paper, filter cloth, or other type of particle retention mechanism) may be present, positioned adjacent to the reactor outlet connected to the reactor outlet conduit 5o. In some embodiments, this retention mechanism 5f may also be positioned adjacent to the reactor inlet within the reactor chamber 5c.

[0084] The purified material 5m can be in particulate form 5p. Figure 9 This example of such particulate material is shown. The size and shape can be any suitable size and shape (e.g., irregular shape, spherical shape, etc.). The size setting can also be in the micrometer or millimeter range as described above (e.g., size between 0.1 micrometer and 5 millimeters, size between 0.1 mm and 5 mm, size between 0.1 micrometer and 5 micrometer, etc.).

[0085] Figure 8 Another example of a purification material 5m is shown, wherein the material comprises a coating 5cl on a carrier material 5s. This purification material may have voids or pores to help provide an improved contact surface area and may also provide some filtration capacity. This material may be used in place of other types of purification materials 5m (e.g., particulate materials, etc.) or in combination with other types of purification materials 5m (e.g., particulate materials, etc.).

[0086] Figure 10 An exemplary embodiment of a method for purifying an electrolyte solution is shown. An embodiment of apparatus 1 can implement an embodiment of this method.

[0087] In the first step S1, an electrolyte solution can be provided. For example, this solution can be provided by using the mixing tank 13 described above, or it can be obtained from the electrolyte solution supplier described above.

[0088] In the second step S2, the electrolyte solution can be purified so that the iron content in the electrolyte solution is at or below a pre-selected iron concentration threshold. For example, this purification can be provided via reactor 5 and / or filtration system FS as discussed above.

[0089] In the third step S3, the purified electrolyte solution can be fed into the storage tank 3 and / or one or more electrolyzers E. For example, at least some of the purified electrolyte solution can be fed directly from the purification unit into the electrolyzers discussed above. As another example, the purified electrolyte solution can be fed into a storage tank and subsequently discharged from the tank for feeding into one or more electrolyzers E discussed above.

[0090] In the optional fourth step S4 (shown in dashed lines), the portable purification system MPS can be separated and moved to a new location to purify the electrolyte solution at that new location. Examples of this process have been discussed above. For instance, this step can be utilized when purification unit 4 is configured as a portable purification system MPS.

[0091] Other embodiments of the method may omit this optional fourth step S4. For example, this particular step may be omitted if the purification unit 4 is not configured as a removable system.

[0092] When the portable purification system MPS is connected to a new location for purification at that new location, steps S1-S3 can be performed again at that new location. Then, step S4 can be performed again, and the portable purification system MPS can be moved to yet another location, allowing the method to be repeated multiple times at several different spaced-apart locations (e.g., different plants, different spaced-apart areas within the same industrial complex, etc.).

[0093] It should be recognized that the embodiments can utilize sensor elements to monitor the impurity content in the electrolyte solution for purification processing. The sensor elements can be located at the outlet of reactor 5, in the filtration system FS, and / or other locations. In cases where a high impurity content is determined in the electrolyte solution, the detection of the electrolyte solution's purity, which is outside the pre-selected impurity concentration standard used in the electrolyte solution, can be used to initiate purification processing.

[0094] It should also be recognized that other modifications can be made to meet a specific set of criteria for different embodiments of device 1 or method. For example, the arrangement of valves, flow meters, temperature sensors, pressure sensors, other sensors, pipes and other conduit elements (e.g., conduit connection mechanisms, tubes, seals, valves, etc.) used to interconnect different units of the device to fluidly connect different components can be arranged to meet a specific facility layout design that takes into account the available area of ​​the device, the instrumentation of specific dimensions of the device, and other design considerations. For example, the size or type of the device can be modified to meet a specific set of design criteria.

[0095] As another example, it is contemplated that specific features described separately or as part of an embodiment may be combined with other separately described features or portions of other embodiments. Therefore, elements and actions of the different embodiments described herein may be combined to provide other embodiments. Thus, while certain exemplary embodiments of methods, apparatuses, systems, and methods of making and using them have been shown and described above, it should be clearly understood that the invention is not limited thereto, but may be implemented and practiced in various other ways within the scope of the appended claims.

Claims

1. A method for purifying electrolytes, the method comprising: Purifying an electrolyte solution such that the iron (Fe) content of the electrolyte solution is at or below a pre-selected Fe concentration threshold, wherein the pre-selected Fe concentration threshold is between 0 ppb Fe and 500 ppb Fe, the purification of the electrolyte solution includes: The electrolyte solution is passed through the reactor to contact the purification material within the reactor chamber for the removal of impurities; and / or Filtering the electrolyte solution to remove impurities from the electrolyte solution; and The purified electrolyte solution is fed into a storage tank or one or more electrolyzers.

2. The method of claim 1, wherein purifying the electrolyte solution comprises passing the electrolyte solution through the reactor to contact purification material in the chamber of the reactor for the removal of impurities.

3. The method of claim 2, wherein purifying the electrolyte solution comprises filtering the electrolyte solution to remove the impurities from the electrolyte solution.

4. The method according to claim 1, wherein the method comprises: The electrolyte solution is formed by mixing the electrolyte material with water and at least one purified material in a mixing tank.

5. The method of claim 4, wherein purifying the electrolyte solution comprises filtering the electrolyte solution to remove the purification material from the electrolyte solution, thereby removing impurities from the electrolyte solution.

6. The method according to claim 5, wherein the method comprises: The electrolyte solution is fed from the mixing tank to at least one filtration system for filtering the electrolyte solution to remove the purified material from the electrolyte solution, thereby removing impurities from the electrolyte solution.

7. The method according to claim 6, wherein the method comprises: The electrolyte solution purified via the at least one filtration system is fed into the storage tank, which is fluidly connected to at least one electrolyzer.

8. The method according to claim 1, wherein the method comprises: The electrolyte solution, purified by purifying the electrolyte solution, is fed into the storage tank, which is fluidly connected to at least one electrolyzer.

9. The method according to claim 1, wherein the method comprises: The electrolyte solution, purified by purifying the electrolyte solution, is fed into the one or more electrolyzers.

10. The method of claim 1, wherein the pre-selected Fe concentration threshold is between 0 ppb and 200 ppb.

11. The method according to claim 1, wherein the method comprises: After the purified electrolyte solution is fed into the storage tank, the portable purification system for purifying the electrolyte solution is separated from the storage tank.

12. The method of claim 11, wherein the method comprises: The portable purification system is moved to another location to purify the electrolyte solution at that location; or The portable purification system was moved to another tank for purifying the electrolyte solution stored therein.

13. An apparatus for purifying an electrolyte solution, the apparatus comprising: A reactor having a chamber in which purified material is retained, the purified material being configured to remove impurities from an electrolyte solution to reduce the iron (Fe) content of the electrolyte solution, thereby forming a purified electrolyte solution having an Fe content equal to or less than a preselected Fe content threshold between 0 ppb Fe and 500 ppb Fe; A reactor inlet conduit is connected to the inlet of the reactor, which may be connected to a source of the electrolyte solution or a storage tank in which the electrolyte solution may be retained; A reactor outlet conduit is connected to the outlet of the reactor, which may be connected to a storage tank and / or an electrolyzer feed conduit to feed purified electrolyte solution that can be output from the reactor into the storage tank and / or at least one electrolyzer.

14. The apparatus of claim 13, wherein the purification material comprises magnesium oxide (MgO) and / or magnesium hydroxide (Mg(OH)2).

15. The apparatus of claim 13, wherein the apparatus further comprises a pump connected to the reactor inlet conduit and a movable base supporting the pump, the reactor inlet conduit, the reactor outlet conduit, and the reactor.

16. The device according to claim 13, wherein the device comprises: The storage tank, wherein the outlet conduit of the storage tank can be connected to a pump to feed the electrolyte solution in the storage tank into the reactor inlet conduit.

17. The apparatus of claim 13, wherein the apparatus comprises: The electrolyzer feed conduit is connected to the reactor outlet conduit to fluidly connect the reactor to the at least one electrolyzer, thereby feeding the purified electrolyte solution that can be output from the reactor into the at least one electrolyzer.

18. An apparatus for purifying an electrolyte solution, the apparatus comprising: A mixing tank, fluidly connected to a source of water, a source of electrolyte material, and a source of purified material, for receiving the water, the electrolyte material, and the purified material for mixing therein to form an electrolyte solution; A filtration system connected to the mixing tank receives the electrolyte solution from the mixing tank and removes particles of the purified material from the electrolyte solution to output a purified electrolyte solution having an iron content less than or equal to a pre-selected iron (Fe) content threshold, the pre-selected Fe content threshold being between 0 ppb Fe and 500 ppb Fe.

19. The apparatus of claim 18, wherein the apparatus comprises: A storage tank, located downstream of the filtration system, to receive the purified electrolyte solution output from the filtration system.

20. The apparatus of claim 19, wherein the apparatus comprises: At least one electrolyzer, the at least one electrolyzer being fluidly connected to the tank to receive the purified electrolyte solution from the tank.

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