Ozone generator and method for producing ozone from oxygen
By using porous materials to fill the cooling fluid channels and sandwich structures in the ozone generator, the problem of low cooling efficiency was solved, thereby improving ozone production and efficiency and adapting to high-pressure gas transportation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- PROMINENT GMBH
- Filing Date
- 2022-05-13
- Publication Date
- 2026-06-26
AI Technical Summary
Existing ozone generators have low ozone output, insufficient cooling efficiency, and limited coolant selection, resulting in inadequate heat dissipation and affecting output and efficiency.
Porous materials are used to fill the cooling fluid channels to improve the heat transfer efficiency of the cooling fluid. The porous metal structure enhances the mechanical stability and electrical contact between the dielectric and the electrode, forming a sandwich structure to increase ozone production.
It significantly improves the ozone output and efficiency of ozone generators, reduces coolant consumption, enhances mechanical stability and electrical contact, and is suitable for high-pressure gas transportation.
Smart Images
Figure CN115367710B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to an ozone generator and a method for producing ozone from oxygen. Background Technology
[0002] An ozone generator is a device that produces ozone from oxygen. For example, ozone is used as a disinfectant in drinking water purification. Ozone is unstable and therefore has a limited shelf life. This means that ozone usually must be produced directly at the intended location.
[0003] For example, ozone can be generated in an electric field. An ozone generator for this purpose includes first and second electrodes with a first dielectric disposed between them. A gas channel is provided between the first dielectric and the first electrode, through which oxygen-containing gas can be transported. The gas (which can be ambient air) is transported through the gas channel and thus through the electric field generated by the two electrodes. Ozone is formed in the electric field.
[0004] When using these ozone generators, typically less than one-fifth of the electrical energy is integrated into the chemical bonds of ozone. More than 80% of the energy is generated as heat.
[0005] This results in a significant increase in the temperature of the gas transported through the gas channel. Unfortunately, the stability of ozone is highly temperature-dependent; the higher the temperature of ozone, the faster it decomposes back into oxygen. Therefore, to increase the ozone output of an ozone generator, it is necessary to cool the ozone generator.
[0006] It is common practice to provide a first cooling fluid channel, the walls of which are at least partially formed by a first dielectric or a second electrode. A cooling fluid (e.g., water) serving as a heat carrier is transported through the cooling fluid channel, such that the cooling fluid cools the surface of the first dielectric or the surface of the second electrode. Because the cooling fluid channel and the gas channel are separated from each other at least by the dielectric, heat must be dissipated through the dielectric.
[0007] Known ozone generators are typically cylindrical, meaning the electrodes and dielectric, as well as the gas and fluid channels, are hollow cylinders arranged coaxially. However, planar configurations are also known.
[0008] In known ozone generators, the coolant flow rate is in the range of 1.3-2 L / g O3. This results in a Reynolds number for the coolant well below the critical value, meaning that the flow type is always laminar, at least at the surface to be cooled within the cooling fluid channels. In laminar flow, the fluid moves in parallel layers. Therefore, heat transfer between layers occurs solely through conduction. Consequently, only low heat transfer can be achieved with laminar flow. Furthermore, in known ozone generators where the coolant is in direct contact with the dielectric, the heat transfer medium must possess a certain degree of conductivity, which limits the choice of heat transfer medium. For ozone generators where electrodes are inserted between the dielectric and cooling water, the electrodes are made of high-alloy stainless steel. However, stainless steel has low thermal conductivity, making the situation even worse for such ozone generators.
[0009] Using known ozone generators, it is impossible to significantly increase the Reynolds number to make the flow turbulent. Furthermore, this would lead to unacceptable water consumption. Additionally, commonly used liquid heat transfer fluids (such as water) have poor thermal conductivity, which limits the overall ozone output of the ozone generator. Summary of the Invention
[0010] Based on the prior art described herein, the object of the present invention is to provide an ozone generator that can achieve increased ozone production compared to known devices.
[0011] According to the present invention, this objective is achieved by filling the cooling fluid channels with a porous material. The porous material provides multiple channels through which the cooling fluid (e.g., water) can be transported, thereby ensuring that not only the portion of the cooling fluid in direct contact with the dielectric in laminar flow participates in heat transfer, but almost all of the cooling fluid participates in heat transfer. The porous structure itself also participates in heat transfer.
[0012] In a preferred embodiment, the cooling fluid passage is used for the flow of cooling liquid, particularly cooling water. It is advantageous if the cooling fluid does not contain gaseous oxygen.
[0013] Preferably, the porous material is a porous body. The porous body can provide support and can contact both the dielectric and the second electrode to maintain a constant distance between them. This is particularly advantageous when the gas pressure in the gas channel is high.
[0014] In a preferred embodiment, the porous material is electrically conductive. It is advantageous for the heat carrier to also be conductive to increase the electric field in the gas channel. However, it is not necessary for the porous material disposed in the cooling fluid channel to be conductive. For example, porous metals can be used herein.
[0015] In another preferred embodiment, the porous material has a thermal conductivity greater than 10 W / mK, preferably greater than 30 W / mK. Due to its higher thermal conductivity than most liquid heat carriers, heat dissipates from the dielectric or second electrode more quickly and efficiently. This also ensures that all cooling fluid participates in heat transfer, as the cooling fluid components flowing through the porous material at locations relatively far from the dielectric also impact the temperature-increasing porous material. In another preferred embodiment, the porous material has a thermal conductivity of 30-50 W / mK.
[0016] Particularly preferably, the porous material is an open-pore material, allowing fluid in the cooling fluid channels to flow through the porous material via numerous interconnected paths. In a preferred embodiment, the volumetric porosity of the porous material is greater than 25%, preferably greater than 50%, and particularly preferably in the range of 55-65%. This ensures that the pressure loss of the heat transfer fluid in the ozone generator does not become too large. Furthermore, a pore size of 0.5-5 mm is advantageous.
[0017] In a preferred embodiment, the cooling fluid channel has an inlet and an outlet, wherein the inlet and outlet, as well as the porous material, are designed such that fluid can be transported from the inlet through the porous material to the outlet, and wherein the inlet and outlet, as well as the porous material, are preferably designed such that liquid can be transported from the inlet through the porous material to the outlet.
[0018] Furthermore, it is advantageous that the ozone generator has a substantially planar sandwich structure, wherein a dielectric is disposed between the first electrode and the second electrode.
[0019] In principle, it is advantageous if the sandwich structure is completely planar, as even minor deviations or small steps will not affect the success of the invention. For example, the two electrodes can be plate-shaped, with a dielectric disposed between the plates, such that gas channels are formed on one side of the dielectric and cooling fluid channels are formed on the other side. The porous material can also be plate-shaped or cubic and disposed, for example, in contact with both the second electrode and the dielectric between the dielectric and the second electrode.
[0020] To further increase the output of the ozone generator, in another embodiment, a third electrode, a second dielectric, a second gas channel through which oxygen-containing gas can be transported, and a second cooling fluid channel whose walls are at least partially formed by the second dielectric or the third electrode, wherein a first electrode is disposed between the second and third electrodes. Essentially, the ozone generator now comprises two gas channels and two fluid channels, wherein the first electrode forms a separate ozone generator relative to the second electrode and relative to the third electrode. Here, the second cooling fluid channel is also preferably designed as a cooling liquid channel.
[0021] High thermal conductivity of the dielectric is particularly preferred. Therefore, the first and / or second dielectric is preferably a ceramic dielectric, preferably Al₂O₃ or AlN ceramic.
[0022] Regarding this method, the above task is achieved through a method for producing ozone from oxygen, which includes the following steps:
[0023] A) Provide the above-mentioned ozone generator.
[0024] B) Apply an electric field between the first and second electrodes.
[0025] C) Transporting oxygen-containing gas through gas channels, and
[0026] D) Cooling fluid, preferably cooling water, is delivered through a cooling channel.
[0027] Further advantages, features, and possible applications will become apparent from the following description of the preferred embodiments and related descriptions. It is shown that: Attached Figure Description
[0028] Figure 1 The diagram shown is a schematic cross-sectional view of one embodiment of the ozone generator of the present invention. Detailed Implementation
[0029] Figure 1 The diagram shown is a schematic cross-sectional view of one embodiment of the ozone generator 1 of the present invention.
[0030] The ozone generator 1 is constructed as a sandwich structure and includes multiple planar or plate-shaped elements. Electrode 2 is shown in the middle. A high voltage can be applied between the first electrode 2 and the second electrode 3. A first dielectric 5 is disposed between the first electrode 2 and the second electrode 3, dividing the remaining space between the electrodes 2 and 3 into a gas channel 7 and a cooling fluid channel 9. Oxygen-containing gas is transported through the gas channel 7. Due to the voltage applied between the first electrode 2 and the second electrode 3, an electric field is formed within the gas channel 7, allowing oxygen molecules to be converted into ozone molecules. However, this generates heat, thus heating the first dielectric 5. The latter is made of a material with high thermal conductivity, i.e., in the illustrated example, of ceramic, particularly Al2O3 or AlN ceramic.
[0031] A first cooling fluid channel 9 is provided on the side of the first dielectric material opposite to the gas channel 7. A cooling fluid, such as water, is transported through it. A porous material 11, i.e., a porous metal in the example shown, is disposed within the cooling fluid channel 9. The porous metal 11 provides electrical coupling between the first dielectric material 5 and the second electrode 3. Furthermore, the porous metal 11 provides mechanical stability.
[0032] Subsequently, cooling fluids such as water can be transported through cooling fluid channels 9 by means of the porous metal 11, thereby allowing heat to be efficiently dissipated from the porous metal.
[0033] The ozone generator has a basically mirror-symmetrical structure, namely, it has a third electrode 4 and a second dielectric 6. The second dielectric 6 is configured to divide the distance between the first electrode 2 and the lower third electrode 4 into a second gas channel 8 and a second cooling fluid channel 10, wherein a second porous material 12 (i.e., porous metal) is disposed in the second cooling fluid channel 10. If a voltage is now applied between the first electrode 2 on one side and the second and third electrodes 3 and 4 on the other side, and oxygen-containing gas is supplied through the two gas channels 7 and 8, ozone is formed therein. The corresponding heat generated is transferred to the porous materials 11 and 12 through the two dielectrics 5 and 6, and the corresponding cooling fluid flows through the porous materials 11 and 12 to dissipate the heat.
[0034] Porous metals can be easily manufactured. For example, aluminum alloys with defined pore structures can be used.
[0035] This invention significantly improves heat transfer from the emission zone (i.e., the two gas channels) to the cooling medium (i.e., the cooling liquid transported through the pores of the porous material). Therefore, less cooling fluid is required, while the efficiency of the ozone generator is significantly increased.
[0036] The conductivity of the metallic structure increases the electrical contact between the dielectric surface and the typically grounded second or third electrode. Therefore, the requirement for minimum conductivity of the heat transfer fluid can be avoided.
[0037] The porous metal structure simultaneously forms a positive-locked connection with the dielectric, thereby stabilizing the typically thin and brittle dielectric. This also allows gas in the gas channel to be transported through the ozone generator at higher pressures without the risk of damaging the dielectric due to high pressure.
[0038] List of reference numerals
[0039] 1. Ozone generator
[0040] 2 First electrode
[0041] 3 Second electrode
[0042] 4 Third electrode
[0043] 5. Dielectric
[0044] 6 Second dielectric
[0045] 7 Gas Channel
[0046] 8 Second Gas Channel
[0047] 9 Cooling fluid channels
[0048] 10 Second Cooling Fluid Channel
[0049] 11 Porous Materials
[0050] 12 Second Porous Material
Claims
1. An ozone generator comprising first and second electrodes, wherein a first dielectric is disposed therebetween, wherein, A gas channel is provided between a first dielectric and a first electrode through which oxygen-containing gas is transported, wherein a first cooling fluid channel is provided, the wall of which is at least partially formed by the first dielectric, characterized in that the cooling fluid channel is filled with a porous material, the cooling fluid channel is designed as a cooling liquid channel, the cooling fluid channel is disposed between the dielectric and the electrode, and the porous material is in contact with both the electrode and the dielectric.
2. The ozone generator as described in claim 1, characterized in that, Porous materials are electrically conductive.
3. The ozone generator as described in claim 2, characterized in that, Porous materials are porous metals.
4. The ozone generator as described in any one of claims 1-3, characterized in that, The thermal conductivity of porous materials is greater than 10 W / mK.
5. The ozone generator as described in claim 4, characterized in that, The thermal conductivity of porous materials is greater than 30 W / mK.
6. The ozone generator as described in claim 5, characterized in that, The thermal conductivity of porous materials is 30-50 W / mK.
7. The ozone generator as described in any one of claims 1-3, characterized in that, Porous materials are open-cell materials.
8. The ozone generator as described in any one of claims 1-3, characterized in that, The cooling fluid channel has an inlet and an outlet, wherein the inlet and outlet, as well as the porous material, are designed to transport fluid from the inlet through the porous material to the outlet.
9. The ozone generator as described in any one of claims 1-3, characterized in that, The ozone generator has a basically planar sandwich structure, wherein a dielectric is disposed between the first and second electrodes.
10. The ozone generator as described in claim 9, characterized in that, in, The porous material is essentially cubic and is disposed between and in contact with the dielectric and the second electrode.
11. The ozone generator as described in claim 9, characterized in that, The device provides a third electrode, a second dielectric, a second gas channel through which oxygen-containing gas is transported, and a second cooling fluid channel whose wall is at least partially formed by the second dielectric or the third electrode, wherein a first electrode is disposed between the second and third electrodes.
12. The ozone generator as described in any one of claims 1-3, characterized in that, The first and / or second dielectric is a ceramic dielectric.
13. The ozone generator as described in claim 12, characterized in that, The first and / or second dielectric is Al2O3 or AlN ceramic.
14. The ozone generator as described in any one of claims 1-3, characterized in that, The volumetric porosity of porous materials is greater than 25%.
15. The ozone generator as described in claim 14, characterized in that, The volumetric porosity of porous materials is greater than 50%.
16. The ozone generator as described in claim 15, characterized in that, The volume porosity of porous materials is in the range of 55%-65%.
17. The ozone generator as described in any one of claims 1-3, characterized in that, Porous materials are formed into porous bodies.
18. The ozone generator as described in claim 17, characterized in that, The porous body serves as a support and defines the distance between the dielectric and the second electrode.
19. A method for producing ozone from oxygen, comprising the following steps: A) Provide an ozone generator as described in any of the preceding claims, B) Apply an electric field between the first and second electrodes. C) Transporting oxygen-containing gas through gas channels, and D) Cooling fluid is delivered through cooling channels.
20. The method as described in claim 19, characterized in that, The cooling fluid is cooling water.