The present invention relates to electrolytic cells, and more particularly, to electrolytic cells having catholyte reservoirs.
Electrolytic cells may be used for the production of various chemistries (e.g., compounds and elements). One application of electrolytic cells is the production of ozone. Ozone is an effective killer of pathogens and bacteria and is known to be an effective disinfectant. The Food and Drug Administration (FDA) approved the use of ozone as a sanitizer for food contact surfaces and for direct application to food products. Accordingly, electrolytic cells have been used to generate ozone and dissolve ozone directly into source water, thereby removing pathogens and bacteria from the water. As a result, electrolytic cells have found application in purifying bottled water products and industrial water supplies.
Illustrative embodiments of the present invention are directed to a cartridge for use with an electrolytic cell having an interface. The cartridge includes a reservoir for containing a catholyte solution. The reservoir is removably coupleable with the cell. The cartridge also includes at least one cartridge port that is removably coupleable to an interface on the electrolytic cell. The port of the cartridge is also configured to cycle a catholyte solution between the reservoir and the electrolytic cell when the cartridge port is coupled to the interface of the electrolytic cell.
In another illustrative embodiment of the cartridge, the cartridge is for use with an electrolytic cell that has an anode and a housing. The cartridge includes a cathode and a reservoir for containing a catholyte solution. The reservoir is configured to provide the catholyte solution to the cathode when the cell is in use and when the reservoir contains the catholyte solution. The cartridge also has a port that is removably coupleable to an interface of the housing of the electrolytic cell. Furthermore, the cathode is spaced from the anode of the electrolytic cell when coupled to the interface of the housing.
Various embodiments of the cartridge may also include a cartridge outlet port for allowing passage of the catholyte solution from the reservoir and a cartridge inlet port for allowing passage of the catholyte solution to the reservoir. Some embodiments may also include at least one valve to prevent the escape of catholyte solution when the cartridge port is decoupled from the interface of the electrolytic cell.
Illustrative embodiments of the present invention are also directed to an apparatus for generating ozone and dissolving ozone into a water source. The apparatus includes a housing forming an interior and an electrolytic cell within the interior. The cell has a cathode, a diamond anode, and a membrane between the cathode and the diamond anode. The apparatus also includes a cartridge that has a reservoir for receiving a catholyte solution. The reservoir is removably coupleable to the electrolytic cell. The cartridge also includes at least one cartridge port in fluid communication with the reservoir. The housing has an interface for removably coupling with the at least one cartridge port. The cartridge port and interface are further configured to cycle a catholyte solution between the reservoir and the cathode.
In exemplary embodiments of the apparatus, the cartridge port includes a cartridge outlet port for allowing the passage of the catholyte solution from the reservoir and a cartridge inlet port for allowing the passage of the catholyte solution to the reservoir. The apparatus may also include corresponding structures on the interface. For example, the interface may include a cathode inlet port for fluid communication with the cartridge outlet port and to allow passage of the catholyte solution from the reservoir to the cathode. Also, the interface may include a cathode outlet port for fluid communication with the cartridge inlet port and to allow passage of the catholyte solution from the cathode to the reservoir. In some embodiments, the interface further includes at least one valve to prevent the escape of catholyte solution when the interface is decoupled from the cartridge port. Additionally or alternatively, the cartridge port includes at least one valve to prevent the escape of catholyte solution when the cartridge port is decoupled from the interface.
In another illustrative embodiment of the apparatus, the apparatus includes a housing having an anode and a cartridge. The cartridge includes a cathode, a reservoir for containing a catholyte solution and for providing the catholyte solution to the cathode. The cartridge has a port that is removably coupleable to an interface of the housing. When coupled to the interface of the housing, the cathode is spaced from the anode of the electrolytic cell.
In other exemplary embodiments, the housing of the apparatus includes an anode inlet port and an anode outlet port such that source water flows through the anode inlet port to contact the anode and then flows through the anode outlet port. In various embodiments of the invention, the anode generates ozone from the source water in contact with the anode and dissolves the ozone in the source water. Additionally or optionally, the apparatus includes at least one valve to prevent the escape of source water when the cartridge is decoupled from the interface of the housing.
In exemplary embodiments of the cartridges and apparatuses described above, the cartridge or apparatus includes a membrane that is spaced between the cathode and the anode. In some embodiments, the electrolytic cell includes the membrane. In other embodiments, the cartridge includes the membrane. Furthermore, in exemplary embodiments, the membrane is a solid proton exchange membrane that provides for the exchange of protons between the cathode and the anode.
In other exemplary embodiments of the cartridges and apparatuses, a catholyte solution is contained within the reservoir. In some embodiments, the catholyte solution is in a solid form. For example, the catholyte solution may be in a pre-mixed powdered form.
In various embodiments of the above described cartridges and apparatuses, the reservoir includes a hydrophobic membrane that contains the catholyte solution while also allowing the passage of hydrogen gas from the reservoir.
In other exemplary embodiments of the cartridges and apparatuses described above, the cartridge or apparatus may include a sensor configured to monitor the performance of the electrolytic cell. The sensor senses, for example, the pH of the catholyte solution, conductivity of the catholyte solution, volume of the catholyte solution, and voltage draw in a power supply of the electrolytic cell. Additionally or alternatively, embodiments of the invention may also include an indicator for indicating when the cartridge needs to be replaced.
The foregoing features of the invention will be more readily understood by reference to the following detailed description, taken with reference to the accompanying drawings, in which:
In illustrative embodiments, an electrolytic cell receives its catholyte solution from a removably coupled cartridge. This cartridge may have a reservoir for containing the catholyte solution, portions of the cell, such as the cathode, or both the reservoir and portions of the cell. Details of various embodiments are discussed below.
During this reaction, it is possible for scale (e.g., calcium carbonate) from the source water to build up or deposit on the anode 120, the cathode 122, or other components of the cell 100. Eventually, if it does build up as noted, the scale impedes the electrochemical reaction within the cell 100. Moreover, such deposits within the electrolytic cell 100 can shorten useful cell life, or require disassembly and cleaning of internal components to restore cell performance and efficient production of target chemistries, such as ozone.
Accordingly, illustrative embodiments of the present invention flow a catholyte solution 110 along a surface of the cathode 122 to prevent the build up of scale on the cathode, thus improving cell efficiency. Without the catholyte solution 110, it is anticipated that the efficiency of the electrolytic cell 100 would decrease.
Any of a variety of catholyte solutions can be used. In illustrative embodiments of the present invention, a catholyte solution 110 with sodium chloride and citric acid facilitates the movement of cations from the anode 120 to the cathode 122. The sodium chloride and citric acid act to “pull” cations through the anode 120, the cathode 122 and ion exchange materials (e.g., a proton exchange membrane) without “clogging” components of the electrolytic cell 100, thereby effectively reducing scale deposits within the cell. Furthermore, citric acid helps regenerate the ion exchange materials used in water softeners by reacting with metal ions to form citrate complexes. In this way, the citric acid strips off the metal ions that accumulate on the ion exchange materials of the cell 100.
Illustrative embodiments of the present invention include a reservoir 104 (e.g., a tank or a container) that supplies the catholyte solution 110 to the cathode 122. To provide a large supply of catholyte solution 110 to the electrolytic cell 100, prior art electrolytic cells known by the inventors imbed the electrolytic cells as portions of larger systems or treatment facilities. When the catholyte solution 110 is depleted, the old catholyte solution is replaced with a new solution. The operation of changing catholyte solution 110 is typically messy and inconvenient. Trained personnel are often required to service such systems to ensure proper replacement and mitigate the mess. Often, redundant elements (e.g., electrolyte tanks and/or piping) are deployed in parallel so that the supply of catholyte solution 110 can be switched to another supply while the first supply is serviced. In other cases, the cathode 122 may be fed by plumbing some of the source water to the cathode. Undesirably, this prior art strategy can decrease the efficiency of the cell 100 because the source water may contain impurities that deposit and/or build up on the surface of the cathode. The inventors discovered that many of these problems could be avoided by using an easily replaceable cartridge 102 containing the catholyte solution 110. The inventors realized the use of illustrative embodiments of such a cartridge 102 1) reduced the complexity of the electrolytic cell 100, 2) typically maintained the useful life of the electrolytic cell, and 3) made the replacement of catholyte solution 110 more user-friendly.
Illustrative embodiments of the present invention thus avoid or significantly lengthen the useful life of electrolytic cells 100 and avoid service calls, cell exchanges, and/or other events that would require intervention from trained personnel. Illustrative embodiments of the present invention use simple and easy to change cartridges 102 that help prevent the deposit of scale and other impurities by collecting and removing the bulk of these impurities from the cathode 122.
As explained above, illustrative embodiments of the electrolytic cell 100 include an anode 120 and a cathode 122 to facilitate the formation of ozone. This electrolytic cell 100 is contained in the interior of a housing 118 (see
The anode 120 is spaced from the cathode 122 in the electrolytic cell 100. To facilitate the movement of protons (e.g., hydrogen cations) from the anode 120 to the cathode 122, in some embodiments, a solid membrane is used as an electrolyte and placed between the anode 120 and cathode 122 (e.g., a proton exchange membrane (PEM), such as Nafion®). Additionally, in some cases, the membrane 136 is used as a barrier to separate the catholyte solution 110 in the cathode 122 from source water flowing in the anode 120. To provide structural integrity to the membrane 136, the membrane may also include a supporting matrix (not shown).
In some embodiments, the anode 120 includes a diamond or a diamond layer that has been deposited by, for example, a chemical vapour deposition process. The diamond layer enables the formation of ozone in the source water supply. In some cases, the diamond is doped with boron, which further enhances the ozone forming properties of the diamond. The cathode 122 correspondingly includes a conductive material such as titanium. The negative electric potential applied to the conductive titanium cathode 122 pulls the hydrogen cations from the anode side of the electrolytic cell 102 towards the cathode side. In some embodiments, the conductive material may be platinum plated to increase its resistance to corrosion. The cathode 122 may also be formed from an expanded metal mesh that creates small passageways and/or pores through which the catholyte solution 110 and reaction by-products may pass. The expanded metal mesh allows for intimate contact between the cathode 122, the catholyte solution 110, and the membrane 136.
The housing 118 or the anode 120 itself includes an anode inlet port 124 and an anode outlet port 126. Piping 128 provides source water to the anode 120 such that the water flows through the anode inlet port 124 to contact the anode 120 (e.g., the diamond layer), and then flows through the anode outlet port 126. As the source water flows past the anode 120, water molecules are broken apart and hydrogen cations are pulled towards the anode 120 while ozone is created from the remaining oxygen. The ozone dissolves directly into the water and starts to kill off bacteria and pathogens, thereby purifying the water. The treated water then flows from the anode 120 through anode outlet port 126 and into piping 128 for use as, for example, drinking water.
The housing 118 and/or the cathode 122 itself includes a cathode inlet port 130 and a cathode outlet port 132. The cartridge inlet port 112 is in fluid communication with the cathode outlet port 132 through piping 134. In a similar manner, the cartridge outlet port 114 is in fluid communication with the cathode inlet port 130 through piping 134. In such an arrangement, catholyte solution 110 flows from the reservoir 104, through the cartridge outlet port 114, and into the piping 134. Then, the catholyte solution 110 flows through the cathode inlet port 130 to contact the cathode 122. In this manner, fresh catholyte solution 110 is supplied to the cathode 122.
As the catholyte solution 110 flows past the cathode 122, it collects the hydrogen bubbles 123 produced by the electrolytic reaction. As explained above, the inventors believe that the catholyte solution 110 also helps “pull” cations through the membrane 136 and may prevent build up of scale on the cathode 122. The depleted (or partially depleted) catholyte solution 110 then exits the cathode 122 through the cathode outlet port 132, flows through the piping 132 and the cartridge inlet port 112, and into the catholyte reservoir 104. In this way, the ports 112, 130, 122, 132 are configured to cycle fresh catholyte solution 110 from the reservoir 104 to the cathode 122, and depleted catholyte 110 back from the cathode to the reservoir.
In some embodiments, as shown in
As the catholyte solution 110 and the gas bubbles 123 flow into the reservoir 104, the bubbles collects at the top of the reservoir. To vent those bubbles 123 from the reservoir 104, some embodiments include a vent 116 in the cartridge. The vent 116 may employ a hydrophobic material as the vent media, but other materials may also be used. The inventors have discovered several factors to be considered in selecting a vent media:
Furthermore, exemplary embodiments of the present invention prevent the deposition of impurities (e.g., calcium carbonate) on the cathode 122 by collecting them in the reservoir 104. To that end, in some embodiments, the reservoir 104 includes a sump construction wherein a ridge or protrusion rises above the cartridge outlet port 114 so that the impurities in the depleted catholyte solution 110 settle under the force of gravity around the port, and are not swept back towards the cathode 122. Alternatively or additionally, the cartridge outlet port 114 may include a screen or filter so that the impurities do not flow through it and back towards the cathode 122.
The cyclical flow of catholyte solution 110 continues until the catholyte solution 110 is consumed (i.e., some or all of its solutes are depleted). Once depleted, the catholyte solution 110 is replaced with a new supply of catholyte solution. Illustrative embodiments of the present invention facilitate the exchange of catholyte solution 110 by simply interchanging the cartridge 102 with a new cartridge 102. To that end, in illustrative embodiments of the invention, the interface 119 delivers a removably coupleable connection for quick and easy exchange of the cartridge 102. The inventors have discovered several factors to be considered in selecting an interface 119:
Furthermore, as noted, the exemplary embodiment of the cartridge 102 shown in
The term “removably coupleable” should be considered in the context of the ozone generation art. For example, one skilled in the art would not consider a cartridge to be “removably coupled” to the housing if it normally must be cut, forcibly broken from the housing, or if it required specialized training-beyond the minimal, “lay-person” training required for the cartridges described herein. Thus, a cartridge that requires significantly less time and complexity to replace, when compared to prior art ozone cartridges known by the inventors, should be considered “removably coupleable.” Below is a summary of some possible removable connections that should provide the desired results.
In the exemplary embodiment shown in
In another exemplary embodiment shown in
It should be emphasized that the examples shown in
Illustrative embodiments of the present invention also aim to provide for quick and easy exchange of catholyte solution 110 without spilling catholyte solution from the cartridge 102 and/or cathode 122. To contain the catholyte solution 110 in the reservoir 104 during the exchange, the cartridge 102 includes valves 138 (e.g., check valves and/or normally closed valves) to seal off the cartridge inlet port 112 and outlet port 114 (see
In
In more specific exemplary embodiments, the valves 138 are integral to the removably coupleable connection of the interface 119 and the cartridge ports 112, 114. In that regard, illustrative embodiments of the present invention may use, for example, HFC series quick couplings supplied by the Colder Products Company™, which facilitate easy replacement of the cartridge while also preventing spillage.
The above described cell and cartridge arrangement 100, 102 is only an illustrative embodiment of the present invention. Other cell and cartridge arrangements 100, 102 are also within the scope of the present invention. For example, piping 134 may be eliminated by directly interfacing the cartridge inlet port 112 with the cathode outlet port 132 and directly interfacing the cartridge outlet port 114 with the cathode inlet port 130. Thus, catholyte solution 110 would flow directly from the reservoir 104 into the cathode 122, and vice versa. In other embodiments, there may be only one port between the cathode 122 and the reservoir 104. In such an embodiment, a first portion of the port may be dedicated to the flow of catholyte solution 110 from the reservoir 104 while a second portion of the port may be dedicated to flow of catholyte solution to the reservoir. In additional or alternative embodiments, the cathode 122 may be disposed within or partially within the reservoir 104.
In this regard,
The electrolytic cell 100 of
In the embodiments shown in
In the embodiment shown in
The cartridge 102 also includes a port 1200 that is removably coupleable to an interface 1202 on a housing 118 of the electrolytic cell 100. In the embodiment of
Various other removably coupleable connections are also within the scope of the present invention. For example, in one specific exemplary embodiment, the port 1200 of the cartridge 102 and the interface 1202 of the electrolytic cell 100 are round. The port 1200 includes a flange around the perimeter of the port. The inner diameter of the flange includes female threads, while the outer diameter of the interface 1202 includes male threads. Using such an arrangement, a user can “screw” the cartridge 102 onto the interface 1202 of the electrolytic cell 100.
In various other exemplary embodiments, the removably coupleable connection uses guides or guide fingers to properly align and/or support the cartridge 102 when installed to the electrolytic cell 100. Once properly aligned, a locking mechanism firmly secures and removably couples the cartridge 102 to the electrolytic cell 100. For example, in some cases, the locking mechanism has an interference fit (e.g., press fit) between the port 1200 and the interface 1202 of the electrolytic cell 100. In other examples, the locking mechanism includes latches, adhesives, screws, snap fittings, and/or bolted assemblies, each of which can be used to firmly secure and removably couple the cartridge 102 to the cell 100.
In the embodiment of
Illustrative embodiments of the present invention include valves 1216, 1218 to prevent spillage of source water when the cartridge 102 is decoupled from the electrolytic cell 100. The electrolytic cell 100 includes an anode inlet port 124 and an anode outlet port 126 so that source water can flow through and contact the anode 120. In the embodiment of
The embodiment shown in
One of the differences between the embodiment of
Additionally, in some embodiments of the present invention, the base portion 1500 includes a protrusion 1508 or a series of protrusions (e.g., ribs) that support the anode 120 when the cartridge 102 is coupled to the base portion 1500. The protrusions 1508 allow for source water to flow through them and contact the anode 120.
Illustrative embodiments of the cartridge 102 use materials that are compatible with the catholyte solution 110, ozone, and by-products of the electrolytic reaction. For example, a small fraction of ozone or other aggressive chemical may cross the membrane 136 and flow into the reservoir 104 of the cartridge 102. Therefore, in some embodiments, the cartridge 102 should be constructed from materials that will withstand the corrosive effects of the chemicals (e.g., metals and ceramics). On the other hand, the lifetime and disposability of the cartridge 102 may also be a factor. The use of cartridge materials that corrode when exposed to aggressive chemicals (e.g., plastics and polymers) may be mitigated by the cost of less expensive materials and/or if the cartridge is replaced before corrosion becomes a problem. In other words, the intended life-span of the cartridge 102 should be considered when selecting materials.
In some embodiments, the reservoir 104 contains a catholyte solution 110 that is in liquid form. In other words, the catholyte solution 110 includes chemical solutes, such as sodium chloride, potassium chloride, citric acid, acetic acid and/or other mild acids, dissolved in water (e.g., solutes include 8.3% of solution by weight). However, transportation and installation of cartridges 102 containing catholyte solutions 110 in liquid form may be expensive and difficult because of the excess weight of the water. Accordingly, in other embodiments of the invention, the solutes are present in the reservoir 104 in dry form. A predetermined amount of solute is present in the reservoir 104 to produce a solution with a predetermined concentration when mixed with water. Once the cartridge 102 is installed, a user can simply add water to dissolve the solutes and produce an appropriate catholyte solution 110. The water can be added manually by a user or, in other embodiments, the water can be added automatically through a replenishment valve 144 (e.g., solenoid valve, see
In further illustrative embodiments of the present invention, there may be a plurality of the above-described cartridges 102 supporting (and removably coupleable) to a single electrolytic cell 100. An arrangement with multiple cartridges 102 may provide redundancy that allows one or more cartridges to be changed without cell 100 down time. In other embodiments, there may be a single cartridge 102 supporting (and removably coupleable) to a plurality of electrolytic cells 100. The single cartridge 102 might support cells 100 generating various ozone output levels and/or plumbed into different water circulation networks. In yet another embodiment, a single electrolytic cell 100 includes a plurality of different removably coupleable cartridges 102. For example, a first cartridge having a reservoir 104 may be removably coupleable to a second cartridge having a cathode 122. The second cartridge, in turn, is removably coupleable to the electrolytic cell 100. This configuration allows for the reservoir 104 and the cathode 122 to be replaced at different time intervals.
Illustrative embodiments of the present invention may also include an indicator to indicate when the catholyte solution 110 is depleted and/or when depletion is imminent. The indicator may be a light or a display device such as an LCD. In some cases, the indicator may automatically shut off power to the cell 100 when the catholyte solution 110 is depleted. The indicator may be triggered by a sensor 140 (or a plurality of sensors) (see
Illustrative embodiments of the present invention may include a microprocessor 142 to control various cell actions and variables (see
Although various exemplary embodiments of the invention have been disclosed, it should be apparent to those skilled in the art that various changes and modifications may be made which will achieve some of the advantages of the invention without departing from the true scope of the invention.
The present application claims the benefit of U.S. Application Ser. No. 61/173,411, filed Apr. 28, 2009, which application is incorporated herein, in its entirety, by reference.
Number | Date | Country | |
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61173411 | Apr 2009 | US |