Process, apparatus and use of an apparatus for producing a plasma-activated liquid
Patent Information
- Application Number
- EP2023739568
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-07-14
- Filing Date
- 2023-07-10
- Publication Date
- 2025-05-21
AI Technical Summary
Existing methods for producing plasma-activated liquids face challenges in controlling the composition of reactive gas streams, leading to uncontrolled reactions and undesirable species formation, making it difficult to achieve a liquid with a desired composition.
A method and device involving multiple plasma sources with different working gases, allowing for separate control of reactive gas streams, which are then applied to a liquid in a controlled manner to produce a plasma-activated liquid with specific properties.
This approach enables predictable and controllable reactions between reactive gas streams, reducing undesirable species like nitrogen oxides and allowing for the production of plasma-activated liquids with desired properties by adjusting plasma sources and gas compositions.
Smart Images
Figure 1.1
Abstract
Description
[0001] Method, device and use of a device for producing a plasma-activated liquid
[0002] The invention relates to a method and a device for producing a plasma-activated liquid, as well as to a use of such a device.
[0003] It is known from the prior art to generate a plasma-activated liquid by introducing a working gas, such as air, into a plasma source and introducing the reactive gas resulting from the reaction of the working gas with the plasma into a starting liquid. Plasma sources are typically used for this purpose, generating a plasma by means of a dielectrically impeded discharge or an arc-like discharge in the working gas.
[0004] This approach has the disadvantage that the composition of the reactive gas stream, especially the composition of the reactive species within it, is not well controllable. In particular, undesirable, uncontrolled reactions can occur in the gas mixture exposed to the plasma.
[0005] These reactions arise partly due to the high temperatures of the gas mixture in the plasma, which prevail, for example, when using an arc discharge, for example an arc discharge generated by means of a pulsed alternating current (for example in the order of a few 10 3K, particularly in the range of 6000 to 8000 K). Relatively large quantities of split nitrogen molecules are detected in an air stream that has been activated by generating a plasma jet using an arc-like discharge. In a plasma generated in air by a dielectrically impeded discharge, lower temperatures are reached, and correspondingly fewer excited particles are available that can split nitrogen. Nevertheless, nitrogen oxide is produced by plasma activation of air, albeit in lower concentrations than with an arc-like discharge.
[0006] In addition, the formation of undesirable species or the degradation of desired species, for example, through reaction with undesirable species, can occur in the plasma-activated working gas. Overall, it is difficult or impossible to produce a plasma-activated liquid with a desired composition using the known processes.
[0007] The present invention is based on the object of improving previously known methods and devices.
[0008] This object is achieved by a method for producing a plasma-activated liquid, in which a first working gas is supplied to a first plasma source and a plasma is generated in the first working gas by the first plasma source, so that the first plasma source provides a first reactive gas stream, in which a further working gas is supplied to a further plasma source and a plasma is generated in the further working gas by the further plasma source, so that the further plasma source provides a further reactive gas stream, and in which a plasma-activated liquid is produced using the first reactive gas stream and the further reactive gas stream, wherein the composition of the first working gas differs from the composition of the further working gas.
[0009] The above-mentioned object is further achieved according to the invention by a device for producing a plasma-activated liquid, comprising a first plasma source which is configured to generate a plasma in a first working gas supplied to the first plasma source, so that a first reactive gas stream is provided, a further plasma source which is configured to generate a plasma in a further working gas supplied to the further plasma source, so that a further reactive gas stream is provided, an activation chamber for receiving a liquid, and a loading device which is configured to load a liquid present in the activation chamber with the first reactive gas stream and the second reactive gas stream.
[0010] The above-mentioned object is also achieved according to the invention by using the device described above or an embodiment thereof for producing a plasma-activated liquid, in particular according to the method described above or an embodiment thereof.
[0011] The method, device, and use can prevent uncontrolled reactions in the working gas or in the reactive gas stream. For example, the generation of nitrogen oxides can be at least reduced.
[0012] For example, reactive gas streams, each of which carries O2 or N2 or has oxidative or reducing properties, can be treated separately from one another, so that they may only come into contact with one another and react with one another in a liquid containing these gas streams.
[0013] Furthermore, by using working gases whose composition is known and adjusted before being introduced to the individual plasma sources, desired reactions can be achieved in the working gas, thus imparting appropriate properties to the reactive gas stream. Furthermore, the process allows the selection of suitable plasma sources and plasma parameters for each individual working gas.
[0014] In particular, this allows the individual gas streams to be separately tempered, for example, by appropriately adjusting the respective plasma sources used. This represents a particular advantage, as temperature is known to influence the reaction rate of chemical reactions, as is particularly the case here in the hot plasma. A plasma-activated liquid is understood to be a liquid that has been activated by the action of a reactive gas stream emerging from an atmospheric plasma source. In particular, the liquid can be directly exposed to atmospheric plasma, such as an atmospheric plasma jet, i.e., to a working gas emerging from a plasma source that is at least partially still in the plasma state.Alternatively, the liquid can also be exposed to the working gas emerging from the plasma source after the working gas has already been recombined, i.e., is no longer in the plasma state. It has been found that even such a recombined working gas still contains sufficient reactive species, such as ozone or nitrogen oxides, to form relatively long-lived reactive species in water, such as hydroxyl radicals, hydrogen peroxide, nitric acid, or nitrous acid.
[0015] Accordingly, the plasma-activated liquid can be produced by the action of a working gas emerging from an atmospheric plasma source on a liquid.
[0016] The device may comprise more than two plasma sources, each generating a plasma in a working gas, so that a reactive gas stream is provided, the compositions of the respective working gases differing from one another.
[0017] The device comprises an activation chamber for accommodating a liquid volume and a plasma source for generating a reactive gas stream by means of electrical discharge in a working gas. The plasma source is connected to the activation chamber in such a way that a reactive gas stream generated by the plasma source is introduced into the activation chamber. In this way, a starting liquid, for example, liquid water or an aqueous solution in the activation chamber, can be exposed to a reactive gas stream, so that reactive species accumulate therein, thus producing a plasma-activated liquid.
[0018] Various embodiments of the method, device, and use are described below, each of which applies individually to the method, device, and use. Furthermore, the individual embodiments can be combined with one another.
[0019] In one embodiment, the plasma-activated liquid is produced by exposing a starting liquid to the first reactive gas stream and the second reactive gas stream. In this way, reactions between multiple reactive gas streams generated by separate plasma sources can be predictably and controllably induced in the exposed liquid. Accordingly, a plasma-activated liquid with specific properties can be provided.
[0020] The starting liquid can be water, an aqueous solution, a solvent, an alcohol-containing solution or similar.
[0021] In one embodiment, the starting liquid is separately exposed to the first reactive gas stream and the second reactive gas stream. This ensures that the individual reactive gas streams do not react with each other before being introduced into the starting liquid. It can also be achieved that a reaction of components of the individual reactive gas streams only occurs in the exposed liquid.
[0022] In a corresponding embodiment, the application device is configured to separately apply the first and the further reactive gas stream to the liquid present in the activation chamber. Preferably, the first reactive gas stream and the further reactive gas stream are introduced into the starting liquid at least partially simultaneously and at different spatial positions, so that the same starting liquid is exposed to the gas at separate spatial locations. Alternatively or additionally, the first reactive gas stream and the further reactive gas stream can be introduced into the starting liquid with a time delay, so that the starting liquid is exposed to the gas at separate spatial locations.
[0023] For the separate exposure of the starting liquid to the first and the further reactive gas streams, the exposure device can be provided with a first exposure element configured to apply the first reactive gas stream to the liquid present in the activation chamber, and with a further exposure element configured to apply the further reactive gas stream to the liquid present in the activation chamber. In this way, separate exposure of the starting liquid can be easily configured, and suitable exposure parameters such as flow rate or velocity as well as temporal synchronization can be set.
[0024] In a further embodiment, the first reactive gas stream and the further reactive gas stream are first mixed to form a single reactive gas stream, and then the starting liquid is exposed to the combined reactive gas stream. In this way, a reaction of components of the individual reactive gas streams can be specifically induced before introduction into the starting liquid.
[0025] In a further embodiment, a gas mixing device is arranged upstream of the application device, which is configured to mix the first and the further reactive gas streams into a common reactive gas stream. The application device is configured to apply the common reactive gas stream to the liquid present in the activation chamber. The gas mixing device can be used to adjust the mixing conditions of the reactive gas streams, for example, the mixing ratios, the mixing speed, or the like. This allows reactions between the individual components of the first reactive gas stream and the further reactive gas stream to be controlled.
[0026] Preferably, the gas mixing device is expediently arranged in the gas flow between the first plasma source and the application device or between the further plasma source and the application device.
[0027] In a further embodiment, the application device is configured to mix the first and the further reactive gas streams and to apply the mixed reactive gas streams to the starting liquid. This eliminates the need for a separate gas mixing device, and the device as a whole can be designed to be compact.
[0028] In a further embodiment, the application device comprises an application element configured to apply a mixture of the first reactive gas stream and the second reactive gas stream to the starting liquid present in the activation chamber. Optionally, the application device can be designed in a modular manner, thus simplifying its maintenance and the replacement of individual application elements.
[0029] In a further embodiment, the first and the further reactive gas streams are brought into contact with a starting liquid separately or as a joint reactive gas stream by means of an application device, wherein the application device comprises a disc aerator, an aeration element made of porous material. In a corresponding embodiment, the application device comprises a disc aerator, an aeration element made of porous material.
[0030] A disc aerator typically has a gas-permeable membrane, for example, a membrane with a multitude, especially hundreds or thousands, of small openings through which the reactive gas stream enters the liquid in the form of small bubbles with a correspondingly large surface area relative to the volume, thereby interacting strongly with the liquid. A similarly strong interaction is achieved by using an aeration element made of porous material, for example, porous ceramic with its large internal surface area.
[0031] A suitable production unit with a disc aerator is known, for example, from EP 3 470 364 A1.
[0032] In a further embodiment, the plasma-activated liquid is produced by subjecting a first starting liquid to the first reactive gas stream, thus providing a first treated liquid, subjecting a second starting liquid to the second reactive gas stream, thus providing a further treated liquid, and obtaining the plasma-activated liquid by mixing the first treated liquid with the further treated liquid. In this way, a plasma-activated liquid can be provided whose properties are based on the composition of several treated liquids.
[0033] The first starting liquid and the further starting liquid can be of the same type, for example water.
[0034] This embodiment also offers the advantage that the plasma-activated liquid can be made available with a temporal and / or spatial delay relative to the generation of the reactive gas streams. For this purpose, for example, the first and the further acted upon liquid can be temporarily stored separately from one another for a certain period of time before being mixed. For example, a first acted upon liquid with oxidative properties and a further acted upon liquid with reducing properties can be stored or transported separately before being mixed at a site of use and reacting with one another to then provide a plasma-activated liquid with the properties of the reacted component of the individual acted upon liquids.
[0035] In a further embodiment, the first and / or the further working gas is a predetermined technical gas. In this way, the composition and, subsequently, the reactions of the working gases can be controlled. Furthermore, technical gases are readily available on the market, so that a device or method in the present embodiment can be easily replicated, at least with regard to the working gas supply.
[0036] In a particular embodiment, the first and / or the further working gas are the result of a gas separation upstream of the individual plasma sources, for example by means of a separation device, which then supplies the individual plasma sources with the corresponding working gas.
[0037] A technical gas is defined as a gas that is produced and used on an industrial scale. In particular, a technical gas has a high degree of purity specified by standards, which is achieved through gas processing. Such a degree of purity can be achieved, for example, with a maximum proportion in the order of 10 -60 or 1 ppm of foreign gases. Industrial gases can be gases consisting of a single element as well as gas mixtures of these pure gases. Gases that have been extracted from natural deposits without further treatment are typically not considered industrial gases. In one embodiment, the first and / or the further working gas comprises one or more of the species or gas mixtures of a predetermined composition selected from the list: O2, N2, noble gas such as Ar, CO2, Cl2, forming gas, N2 mixed with one or more noble gases, H2 mixed with one or more noble gases.
[0038] In a further embodiment, the first reactive gas stream is generated by means of an electrical discharge in the first working gas. Alternatively or additionally, the further reactive gas stream is generated by means of an electrical discharge in the further working gas. The electrical discharge is a dielectrically impeded discharge, a high-frequency arc-like discharge, a direct current arc discharge, or a discharge generated by means of a microwave jet nozzle.
[0039] In a corresponding embodiment, the first plasma source and / or the further plasma source is configured to generate a plasma by means of electrical discharge in a working gas, wherein the electrical discharge is a dielectrically impeded discharge, a high-frequency arc-like discharge, a direct current arc discharge, or a discharge generated by means of a microwave jet nozzle.
[0040] In this way, plasma sources that are already available on the market can be used.
[0041] By providing or using a plasma source which is designed to generate the reactive gas stream by means of an arc-like electrical discharge, in particular a high-frequency arc-like discharge, in a working gas, a high concentration of certain reactive species can be generated in the gas stream, in particular fully or partially ionized or excited atoms or molecules.To generate a reactive gas flow by means of a high-frequency arc-like discharge in a working gas, a plasma source is preferably used with an electrically conductive nozzle tube having a downstream nozzle opening from which the reactive gas flow emerges during operation, and with an upstream working gas inlet connected to the nozzle opening via a flow channel, wherein an internal electrode is arranged in the flow channel, and wherein a high-frequency high voltage can be applied between the internal electrode and the nozzle tube.
[0042] To operate this arc-type plasma source, a working gas is introduced into the working gas inlet, and a high-frequency high voltage is applied between the inner electrode and the nozzle tube, creating an arc-like discharge between the inner electrode and the nozzle tube, with which the working gas flow interacts. The working gas is at least partially converted into the plasma state, so that a reactive gas flow emerges from the nozzle opening of the plasma nozzle in the form of an atmospheric plasma jet. Preferably, a high-frequency high voltage with a voltage in the range of 1-100 kV, preferably 1-50 kV, more preferably 10-50 kV, and a frequency of 1-300 kHz, in particular 1-100 kHz, preferably 10-100 kHz, more preferably 10-50 kHz, is applied between the inner electrode and the nozzle tube.
[0043] Alternatively or additionally, a plasma source can be provided or used that is configured to generate the reactive gas stream by means of a dielectrically impeded discharge in a working gas. A dielectrically impeded discharge can generate very high concentrations of certain reactive species, particularly ozone, in the gas stream. Using such a reactive gas stream to produce a plasma-activated liquid can induce the formation of hydroxyl radicals in the liquid, which provide a good disinfection effect.To generate a reactive gas flow by means of a dielectric barrier discharge in a working gas, a plasma source is preferably used with an electrically conductive nozzle tube having a downstream nozzle opening from which the reactive gas flow emerges during operation, and with an upstream working gas inlet connected to the nozzle opening via a flow channel. The flow channel preferably runs at least partially between the nozzle tube and a DBD electrode, with a dielectric being arranged between the nozzle tube and the DBD electrode, and a high-frequency high voltage being applied between the DBD electrode and the nozzle tube.
[0044] To operate this DBD plasma source, a working gas is introduced into the working gas inlet, and a high-frequency high voltage is applied between the DBD electrode and the nozzle tube. Since the dielectric impedes direct discharges between the DBD electrode and the nozzle tube, dielectrically impeded discharges occur in the section of the flow channel running between the DBD electrode and the nozzle tube. These discharges excite the working gas flow conducted through the flow channel and / or enrich it with reactive species, causing a reactive gas flow to exit the nozzle opening. Preferably, a high-frequency high voltage with a voltage in the range of 5 to 15 kV and a frequency in the range of 7.5 to 25 kHz, in particular 13 to 14 kHz, is applied between the DBD electrode and the nozzle tube.
[0045] A direct current arc discharge can be generated, for example, using a plasma spray nozzle. In this case, the discharge is not pulsed but applied over a predetermined time window, and the temperatures in the working gas or in the immediate vicinity of the discharge are typically several thousand Kelvin.
[0046] In a further embodiment, a first working gas source is provided and configured to supply a first working gas to the first plasma source, and a further working gas source is provided and configured to supply a further working gas to the further plasma source, wherein the composition of the first working gas differs from the composition of the further working gas.
[0047] This allows not only the parameters of the plasma source itself to be adjusted individually for each working gas, but also the composition and, accordingly, the properties of the respective working gases. For example, a first working gas and a second working gas, which would react if mixed together beforehand, can be treated separately with plasma according to their respective intrinsic properties.
[0048] Preferably, the first plasma source is connected to a first working gas source, and the second plasma source is connected to a second working gas source, with the first and second working gas sources being separate from each other. In this way, the composition of the first and second working gases can be easily controlled.
[0049] In a further embodiment, the device comprises a control device configured to control the operation of the device. The control device may, in particular, comprise a memory containing instructions whose execution on at least one microprocessor of the control device effects the control of the device.
[0050] Further features and advantages of the method, the device and the use will become apparent from the following description of embodiments, with reference to the accompanying drawings.
[0051] In the drawing show
[0052] Fig. 1 shows a plasma source in the form of a plasma nozzle for generating an atmospheric plasma jet by means of an arc-like discharge, Fig. 2 shows a plasma source in the form of a nozzle for generating a reactive gas stream by means of a dielectrically impeded discharge,
[0053] Fig. 3 shows a first embodiment of a device for producing a plasma-activated liquid in a schematic view,
[0054] Fig. 4 shows a second embodiment of a device for producing a plasma-activated liquid in a schematic view,
[0055] Fig. 5 shows a third embodiment of a device for producing a plasma-activated liquid in a schematic view,
[0056] Fig.6 shows a fourth embodiment of a device for producing a plasma-activated liquid in a schematic view.
[0057] Fig. 1 shows a schematic sectional view of a plasma source 2 in the form of a plasma nozzle for generating a reactive gas stream 26 in the form of an atmospheric plasma jet by means of an arc-like discharge,
[0058] The plasma nozzle 2 has a metal nozzle tube 4 that tapers conically to a nozzle opening 6. At the end opposite the nozzle opening 6, the nozzle tube 4 has a swirl device 8 with an inlet 10 for a gas stream, in particular a working gas, for example, air or nitrogen.
[0059] An intermediate wall 12 of the swirl device 8 has a ring of circumferentially inclined bores 14 through which the gas flow is guided. The downstream, conically tapered portion of the nozzle tube is therefore flowed through by the gas flow in the form of a vortex 16, the core of which runs along the longitudinal axis of the nozzle tube. An internal electrode 18 is arranged centrally on the underside of the intermediate wall 12 and projects coaxially into the nozzle tube in the direction of the tapered section. The electrode 18 is electrically connected to the intermediate wall 12 and the remaining parts of the swirl device 8. The swirl device 8 is electrically insulated from the nozzle tube 4 by a ceramic or quartz glass tube 20. A high-frequency high voltage, generated by a transformer 22, is applied to the electrode 18 via the swirl device 8. The inlet 10 is supplied with a gas stream 23 via a line not shown. The nozzle tube 4 is grounded.The applied voltage generates a high-frequency discharge in the form of an arc 24 between the electrode 18 and the nozzle tube 4.
[0060] The terms "arc," "arc discharge," and "arc-like discharge" are used here as a phenomenological description of the discharge, since the discharge occurs in the form of an arc. The term "arc" is also used elsewhere as a discharge form for DC discharges with essentially constant voltage values. In this case, however, it is a high-frequency discharge in the form of an arc, i.e., a high-frequency, arc-like discharge.
[0061] However, due to the swirling flow of the working gas, this arc is channeled in the vortex core on the axis of the nozzle tube 4, so that it only branches out to the wall of the nozzle tube 4 in the area of the nozzle opening 6. The working gas, which rotates at high flow velocity in the area of the vortex core and thus in the immediate vicinity of the arc 24, comes into intimate contact with the arc and is thereby partially converted into the plasma state, so that an atmospheric plasma jet 26 exits the plasma nozzle 2 through the nozzle opening 6.
[0062] Fig. 2 shows a perspective, schematic sectional view of another plasma source 32 in the form of a nozzle for generating a reactive gas stream by means of dielectric barrier discharge. The nozzle 32 has a metal nozzle tube 34, at the upstream end 35 of which a distributor head 36 is arranged with an inlet 37 for a gas stream 38, for example, air, and with an annular distribution channel 40. At the opposite downstream end 42 of the nozzle tube 34, an outlet nozzle 44 with a nozzle opening 46 is arranged, from which the reactive gas stream 38 enriched with reactive species emerges during operation.
[0063] A ceramic tube 48 extends from the distributor head 36 through the nozzle tube 34 into the outlet nozzle 44 such that an annular discharge channel 50 extends from the distributor channel 40 between the nozzle tube 34 and the ceramic tube 48 to the outlet nozzle 44. Instead of a ceramic tube, a tube made of quartz glass, for example, can also be considered.
[0064] On the inside of the ceramic tube 48, a tubular high-voltage electrode 52 made of metal is arranged. This electrode is connected via a high-voltage cable 54 to a transformer 56, which can be used to apply a high-frequency high voltage between the high-voltage electrode 52 and the grounded nozzle tube 34, which acts as a counter electrode. Instead of a tubular high-voltage electrode 52, a differently shaped high-voltage electrode, for example, in the form of a rounded sheet, is also possible.
[0065] Insulating plugs 58 are arranged in the ceramic tube 48, which enclose the high-voltage electrode 52 and further prevent working gas from flowing into the area of the high-voltage electrode 52 or out of the nozzle 32 through the ceramic tube 48. Furthermore, a sealing ring 60 is inserted into an annular groove 62 on the distributor head 36, which seals the distributor head 36 to the ceramic tube 48.
[0066] A coolant line 64 may be provided around the nozzle tube 34, through which a coolant can be passed during operation to cool the nozzle tube 34. The coolant line 64 may, for example, run spirally around the nozzle tube 34, as shown.
[0067] In operation, a gas stream 38 is introduced through the inlet 37 into the distributor head 36 so that the gas stream 38 flows through the annular discharge channel 50.
[0068] With the transformer 56, a high-frequency high voltage is applied between the high-voltage electrode 52 and the nozzle tube 34, so that dielectrically impeded discharges occur in the discharge channel 50 in the region of the high-voltage electrode 52, by means of which reactive species, in particular ozone, are generated in the gas stream 38 flowing there.
[0069] The reactive gas stream 38 enriched with the reactive species exits the nozzle opening 46.
[0070] Fig. 3 shows a first embodiment of a device 70 for plasma activation of a liquid. The device 70 comprises a first plasma source 72, a second plasma source 74, and an activation chamber 76 for receiving a liquid 78, here water.
[0071] The first plasma source 72 is designed as a nozzle for generating a reactive gas stream by means of a dielectrically impeded discharge. The second plasma source 74 is designed as a plasma nozzle for generating a reactive gas stream in the form of an atmospheric plasma jet by means of an arc-like discharge. The first and the further plasma sources 72, 74 each have a gas inlet 80, 82 configured to supply a working gas 94, 96 to the corresponding plasma source 72, 74.
[0072] The activation chamber 76 has a pressurization device 84 with a first pressurization element 86 and a second pressurization element 88, both designed as disc aerators. The first pressurization element 86 is fluidically connected to the first plasma source 72, so that a first reactive gas stream 90 emerging from the first plasma source 72 can enter the activation chamber 76 via the first pressurization element 86. Likewise, the second pressurization element 88 is fluidically connected to the second plasma source 74, so that a second reactive gas stream 92 emerging from the second plasma source 74 can enter the activation chamber 76 via the second pressurization element 88. The first and second application elements 86, 88 are designed and arranged separately from one another such that the first reactive gas stream 90 and the second reactive gas stream 92 only meet in the activation space 76.
[0073] The device schematically illustrated in Fig. 3 is operated as follows. The first plasma source 72 is supplied with a first working gas stream 94 via the first gas inlet 80, and the second plasma source 74 is supplied with a second working gas stream 96 via the second gas inlet 82. This supply occurs in a flow-through and parallel manner from separate working gas sources (not shown here), with the first working gas 94 being a nitrogen-containing technical gas and the second working gas 96 being an oxygen-containing technical gas.
[0074] The first plasma source 72 generates a dielectrically impeded discharge in the nitrogen-containing first working gas 94. This transforms the first working gas 94 into a first reactive gas stream 90, which is guided in a flow from the first plasma source 72 to the first impingement element 86. There, the first reactive gas stream 90 is introduced as fine gas bubbles 98 through the porous structure of the first impingement element 86, which is designed as a disc aerator, into the water 78 absorbed by the activation chamber 76.
[0075] In parallel, the second plasma source 74 generates an arc-like discharge in the oxygen-containing second working gas 96, which is then converted into a corresponding reactive gas stream 92 and guided to the second application element 88. There, the second reactive gas stream 92 is introduced into the water 78 of the activation chamber 76 separately from the first reactive gas stream 90 emerging from the first plasma source 72.
[0076] In the activation chamber 76, the first and second reactive gas streams 90, 92 react with the water 78 and with each other to produce plasma-activated water.
[0077] Fig. 4 shows a second embodiment of a device 100 for producing a plasma-activated liquid in a schematic view. This device 100 has, as in Fig. 3, a first plasma source 102, a second plasma source 104, and an activation chamber 106 for receiving a liquid 108—here, an alcohol-containing solvent—with a pressurizing device 110. In the embodiment of Fig. 4, however, the device is designed such that the pressurizing device 110 is a uniform ventilation element made of a porous material, which is fluidically connected to both the first and second plasma sources 102, 104. Furthermore, the first and second plasma sources 102, 104 are both configured to generate a reactive gas flow by means of an arc-like discharge in a working gas.
[0078] During operation, a first working gas 112 is supplied to the first plasma source 102, and a second working gas 114 is supplied to the second plasma source 104 via the respective gas inlets 116, 118. The first plasma source 102 generates a first reactive gas stream 120, while the second plasma source 104 generates a second reactive gas stream 122. The first and second reactive gas streams 120, 122 are then fed in parallel and simultaneously to the application device 108, where they are introduced into the alcohol-containing solvent 110 of the activation chamber 106.
[0079] Fig. 5 shows a third embodiment of a device 130 for producing a plasma-activated liquid in a schematic view. Here, too, a first plasma source 132, a second plasma source 134, and an activation chamber 136 with a liquid 138 are shown. The first plasma source 132 and the second plasma source 134 are both designed to generate a reactive gas flow by means of a dielectrically impeded discharge in a working gas and each have a gas inlet 140, 142, which are separate from one another. In addition, the first plasma source 102 has a first gas outlet 144, which is fluidly connected to a gas mixing device 146. Likewise, a second gas outlet 148, which is fluidly connected to the gas mixing device 146, is provided on the second plasma source 134.
[0080] The gas mixing device 146 is in turn fluidically connected to a pressurizing device 150 of the activation chamber 136. Thus, the gas mixing device 146 is positioned upstream of the pressurizing device 150 in the gas flow. The pressurizing device 150 is designed as a disc aerator.
[0081] For plasma activation of the liquid 138 contained in the activation chamber, the first and second plasma sources 132, 134 are each supplied with a working gas 152, 154, wherein the compositions of the respective working gases 152, 154 are different. The first and second plasma sources 132, 134 generate a plasma in parallel in the first and second working gases 152, 154, respectively, and thus also a first reactive gas stream 156 and a second reactive gas stream 158, which are each fed to the gas mixing device 146.
[0082] In the gas mixing device 146, the first reactive gas stream 156 and the second reactive gas stream 158 are mixed together and subsequently fed to the application device 150 as a common reactive gas stream 160. There, the common reactive gas stream 160 is brought into contact with the liquid 138 in the activation chamber 136 and mixed with it to thereby provide a plasma-activated liquid. In this process, the first reactive gas stream 156 and the further reactive gas stream 158 are first mixed to form a common reactive gas stream 160, and then
[0083] Starting liquid is exposed to the common reactive gas stream 160.
[0084] Fig. 6 shows a fourth embodiment of an apparatus 170 for producing a plasma-activated liquid in a schematic view. A first plasma source 172 and a second plasma source 174 are provided, both configured to generate a reactive gas stream 176, 178 by means of an arc-like discharge in a working gas. Furthermore, a first activation chamber 180 containing a first liquid 182 and a second activation chamber 184 containing a second liquid 186 are provided, each activation chamber 180, 182 having a pressurizing device 188, 190.
[0085] The first plasma source 172 is fluidly connected to the first activation chamber 180 or to the application device 188 of the first activation chamber 180. In addition, the second plasma source 174 is fluidly connected to the second activation chamber 184 or to the application device 190 of the second activation chamber 184.
[0086] The device 170 further comprises a mixing container 192 which is fluidly connected to the first activation chamber 180 and to the second activation chamber 184.
[0087] To provide a plasma-coated liquid, the first plasma source 172 is supplied with a first working gas 194 and the second plasma source 174 is supplied with a second working gas 196 in parallel. The first plasma source 172 generates a plasma in the first working gas 194, and the resulting first reactive gas stream 176 flows from the first plasma source 172 to the application device 188 and is thus mixed with the liquid 182 in the first activation chamber 180. In addition and at the same time, the second plasma source 174 generates a second reactive gas stream 178 by discharging in the second working gas 196, wherein the second reactive gas stream 178 is fed to the application device 190 of the second activation chamber 184 and is supplied to the liquid 186 present in the second activation chamber 184.
[0088] Thus, a first liquid 198, which is exposed to the first reactive gas stream, is provided in parallel in the first activation chamber 180, and a second liquid 200, which is exposed to the second reactive gas stream, is provided in the second activation chamber 183. In a further process step, the first exposed liquid 198 and the second exposed liquid 200 are fed to the mixing container 192 and mixed therein to form a plasma-activated liquid 202.
[0089] It is also conceivable to provide three liquids 182, 186 and 202 each in a container, to subject only two of them to a reactive gas stream, and then to mix these two liquids with the third liquid.
Claims
Patent claims Method for producing a plasma-activated liquid (202), in which a first working gas (94, 112, 152, 194) is supplied to a first plasma source (72, 102, 132, 172) and a plasma is generated in the first working gas (94, 112, 152, 194) with the first plasma source (72, 102, 132, 172), so that the first plasma source (72, 102, 132, 172) provides a first reactive gas stream (90, 120, 156, 176), in which a further working gas (96, 114, 154, 196) is supplied to a further plasma source (74, 104, 134, 174) and a further plasma source (74, 104, 134, 174) a plasma is generated in the further working gas (96, 114, 154, 196), so that the further plasma source (74, 104, 134, 174) provides a further reactive gas stream (92, 122, 158, 178), and in which a plasma-activated liquid (202) is produced using the first and the further reactive gas stream (90, 120, 156, 176, 92, 122, 158, 178),wherein the composition of the first working gas (94, 112, 152, 194) differs from the composition of the further working gas (96, 114, 154, 196). The method according to claim 1, wherein the plasma-activated liquid (202) is produced by exposing a starting liquid (78, 110, 138, 182, 186) to the first reactive gas stream (90, 120, 156, 176) and the further reactive gas stream (92, 122, 158, 178). Method according to claim 2, characterized in that the starting liquid (78, 110, 138, 182, 186) is separately exposed to the first reactive gas stream (90, 120, 156, 176) and the further reactive gas stream (92, 122, 158, 178). Method according to claim 2, characterized in that the first reactive gas stream (90, 120, 156, 176) and the further reactive gas stream (92, 122, 158, 178) are first mixed to form a common reactive gas stream (160) and then the starting liquid (78, 110, 138, 182, 186) is exposed to the common reactive gas stream (160).The method according to claim 1, wherein the plasma-activated liquid (202) is produced by subjecting a first starting liquid (182) to the first reactive gas stream (176), thus providing a first acted-upon liquid (198), subjecting a second starting liquid (186) to the second reactive gas stream (178), thus providing a further acted-upon liquid (200), and obtaining the plasma-activated liquid (202) by mixing the first acted-upon liquid (198) with the further acted-upon liquid (200). The method according to any one of claims 1 to 5, wherein the first working gas (94, 112, 152, 194) and / or the further working gas (96, 114, 154, 196) is a predetermined technical gas. Method according to one of claims 1 to 6, wherein the first reactive gas stream (90, 120, 156, 176) is generated by means of electrical discharge in the first working gas (94, 112, 152, 194), and / or. in which the further reactive gas stream (92, 122, 158, 178) is generated by means of electrical discharge in the further working gas (96, 114, 154, 196), wherein the electrical discharge is a dielectrically impeded discharge, a high-frequency arc-like discharge, a direct current arc discharge or a discharge generated by means of a microwave jet nozzle.
8. The method according to any one of claims 1 to 7, wherein the first reactive gas stream (90, 120, 156, 176) and the further reactive gas stream (92, 122, 158, 178) are brought into contact with a starting liquid (78, 110, 138, 182, 186) separately or as a common reactive gas stream (160) by means of an application device (84, 108, 150, 188, 190), wherein the application device (84, 108, 150, 188, 190) comprises a disk aerator, an aeration element made of porous material.
9. Device (70, 100, 130, 170) for producing a plasma-activated liquid (202) with a first plasma source (72, 102, 132, 172) which is designed to generate a plasma in a first working gas (94, 112, 152, 194) supplied to the first plasma source (72, 102, 132, 172), so that a first reactive gas stream (90, 120, 156, 176) is provided, with a further plasma source (74, 104, 134, 174) which is designed to generate a plasma in a further working gas (96, 114, 154, 196) supplied to the further plasma source (74, 104, 134, 174), so that a further reactive gas stream (92, 122, 158, 178) is provided, with an activation chamber (76, 106, 136, 180, 184) for receiving a liquid and with a loading device (84, 108, 150, 188, 190) which is designed to contact a liquid (78, 110, 138, 182, 186) present in the activation chamber (76, 106, 136, 180, 184) with the first reactive gas stream (90, 120, 156,176) and second reactive gas stream (92, 122, 158, 178). Device (70, 100, 130, 170) according to claim 9, characterized in that the application device (84, 108, 150, 188, 190) is designed to apply the first reactive gas stream (90, 120, 156, 176) and the second reactive gas stream (92, 122, 158, 178) separately to the liquid (78, 110, 138, 182, 186) present in the activation space (76, 106, 136, 180, 184). Device (70, 100, 130, 170) according to claim 9, characterized in that the application device (150) is preceded by a gas mixing device (146) which is designed to mix the first reactive gas stream (156) with the second reactive gas stream (158) in a common reactive gas stream (160), and in that the application device (150) is designed to apply the common reactive gas stream (160) to the liquid (138) present in the activation space (136). Device (70, 100, 130, 170) according to one of claims 9 to 11, characterized in thatthat a first working gas source is provided and configured to supply a first working gas (94, 112, 152, 194) to the first plasma source (72, 102, 132, 172), and that a further working gas source is provided and configured to supply a further working gas (96, 114, 154, 196) to the further plasma source (74, 104, 134, 174), wherein the composition of the first working gas (94, 112, 152, 194) differs from the composition of the further working gas (96, 114, 154, 196). Device (70, 100, 130, 170) according to one of claims 9 to 12, characterized in that the first plasma source (72, 102, 132, 172) and / or the further plasma source (74, 104, 134, 174) is configured to generate a plasma by means of electrical discharge in a working gas (94, 112, 152, 194, 96, 114, 154, 196), wherein the electrical discharge is a dielectrically impeded discharge, a high-frequency arc-like discharge, a direct current arc discharge, or a discharge generated by means of a microwave jet nozzle. Device (70, 100, 130, 170) according to one of claims 9 to 13, characterized in that the application device (84, 108, 150, 188, 190) comprises a disc aerator, an aeration element made of porous material. Use of a device (70, 100, 130, 170) according to one of claims 9 to 14 for producing a plasma-activated liquid, in particular according to a method according to one of claims 1 to 8.