Method, apparatus for producing a plasma-activated liquid, and use of the apparatus

Abstract

A method for producing a plasma activation liquid (202) is proposed, in which a first working gas (94, 112, 152, 194) is supplied to a first plasma source (72, 102, 132, 172), and the first plasma source (72, 102, 132, 172) generates plasma in the first working gas (94, 112, 152, 194), thereby providing a first reactive gas stream (90, 120, 156, 176). A further working gas (96, 114, 154, 196) is supplied to a further plasma source (74, 104, 134, 174), and the further plasma source (74, 104, 134, 174) generates plasma in the further working gas (96, 114, 154, 196), thereby providing a further reactive gas stream (92, 122, 158, 178). The plasma activation liquid (202) is produced using the first reactive gas stream and the further reactive gas stream (90, 120, 156, 176, 92, 122, 158, 178), and the composition of the first working gas (94, 112, 152, 194) is different from the composition of the further working gas (96, 114, 154, 196). An apparatus (70, 100, 130, 170) configured accordingly, and the use of such an apparatus for producing a plasma activation liquid (202) are also described.

Description

Technical Field

[0001] The present invention relates to a method and an apparatus for producing a plasma activation liquid, and to the use of such an apparatus.

Background Art

[0002] From the state of the art, it is known to introduce a working gas, such as air, into a plasma source for generating a plasma activation liquid, and to introduce a reactive gas resulting from the reaction of the working gas and the plasma into a starting liquid. A plasma source that generates plasma in a working gas by a dielectrically impeded discharge or an arc-like discharge is usually used for this purpose.

[0003] This procedure has the disadvantage that the composition of the reactive gas stream, in particular the composition of the reactive species therein, cannot be easily controlled. In particular, unwanted uncontrolled reactions can occur in the gas mixture exposed to the plasma.

[0004] These reactions are partly favored when using an arc discharge, such as an arc discharge generated by a pulsed alternating current, in a high-temperature gas mixture (e.g., on the order of several 10 3 K, in particular in the range of 6000 to 8000 K) in the plasma. Thus, in an air stream activated by generating a plasma jet by an arc-type discharge, a relatively large amount of dissociated nitrogen molecules can be found. In a plasma generated in air by a dielectrically impeded discharge, since a lower temperature is reached, the number of excited particles available for dissociating nitrogen decreases. Nevertheless, by plasma activation of air, nitrogen oxides are produced, although at a lower concentration than by an arc-type discharge.

[0005] In addition, in the plasma activation working gas, the formation of unwanted species or the decomposition of desired species can occur, for example, by reaction with unwanted species. Overall, it is difficult or impossible to produce a plasma activation liquid having a desired composition using known methods.

[0006] Methods for providing a plasma-activated liquid are known, for example, from Patent Document 1, in which two gas products are mixed in a mixing chamber. In addition, Patent Document 2 discloses two plasma sources for the parallel generation of reactive gas flows, which are used to pressurize a liquid only after they have been initially mixed.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Means for Solving the Problems

[0008] The present invention is based on the problem of improving conventionally known methods and apparatuses.

[0009] This problem is solved by a method for producing a plasma-activated liquid, in which a first working gas is supplied to a first plasma source, and plasma is generated in the first working gas by the first plasma source, whereby the first plasma source provides a first reactive gas stream, a further working gas is supplied to a further plasma source, and plasma is generated in the further working gas by the further plasma source, whereby the further plasma source provides a further reactive gas stream, and the plasma-activated liquid is produced using the first reactive gas stream and the further reactive gas stream, and the composition of the first working gas is different from the composition of the further working gas Rather, the plasma-activated liquid is produced by causing a first starting liquid to act on a first reactive gas flow to provide a first working liquid, causing a second starting liquid to act on a second reactive gas flow to provide a further working liquid, and obtaining the plasma-activated liquid by mixing the first working liquid and the further working liquid.

[0010] The above problem is further solved by an apparatus for producing a plasma-activated liquid according to the present invention, the apparatus having a first plasma source and a second plasma source, in which apparatus a first activation chamber having a first liquid and a second activation chamber having a second liquid are provided, each activation chamber including an actuator, the first plasma source being in fluid connection with the first activation chamber or the actuator of the first activation chamber, the second plasma source being in fluid connection with the second activation chamber or the actuator of the second activation chamber, the first plasma source and the second plasma source being configured to generate a reactive gas flow by an arc-like discharge in a working gas, the apparatus being such that a first working gas is supplied to the first plasma source and a second working gas is supplied to the second plasma source in parallel, the first plasma source generating plasma in the first working gas, and the resulting first reactive gas flow flowing from the first plasma source to the actuator and being mixed with the liquid in the first activation chamber, and in parallel and simultaneously, the second plasma source generating a second reactive gas flow by a discharge in the second working gas, the second reactive gas flow being sent to the second activation chamber of the actuator and supplied to the liquid present in the second activation chamber, whereby a first liquid acted upon by the first reactive gas flow in the first activation chamber is provided, and in parallel a second liquid acted upon by the second reactive gas flow in the second activation chamber is provided, and the apparatus being designed in such a way that it has a mixing vessel in fluid connection with the first activation chamber and the second activation chamber, whereby the first working liquid and the second working liquid are sent to the mixing vessel where they are mixed to form a plasma-activated liquid.

[0011] p Apparatus for producing a plasma-activated liquid is also disclosed, a first plasma source configured to generate plasma in a first working gas supplied to the first plasma source so as to provide a first reactive gas flow, and a further plasma source configured to generate plasma in a further working gas supplied to the further plasma source so as to provide a further reactive gas flow, an activation chamber for receiving a liquid, and an actuator configured to impinge the liquid present in the activation chamber with the first reactive gas flow and the second reactive gas flow.

[0012] According to the present invention, the above problems are also solved by using the above-described apparatus or an embodiment thereof for producing a plasma-activated liquid, in particular according to the above-described method or an embodiment thereof.

[0013] By the methods, apparatuses, and uses described, uncontrolled reactions in the working gas or reactive gas flow can be avoided. For example, the production of nitrogen oxides can be at least reduced. For example, reactive gas flows, each of which is a carrier of O2 or N2 or has oxidation or reduction properties, can be separated from each other and treated so that they contact and react with each other only in the liquid to which these gas flows are applied.

[0014] In addition, in order to impart characteristics corresponding to the reactive gas flow, a desired reaction in the working gas can be set by using a working gas having a known composition that is adjusted before the working gas is introduced into the individual plasma sources. In addition, for the individual working gases in this method, a suitable plasma source or plasma parameters can be selected.

[0015] In particular, this makes it possible to separately temperature-regulate the individual gas flows, for example by appropriately adjusting each of the plasma sources used. Since it is known that temperature affects the reaction rate of chemical reactions, and this is also the case here, especially for high-temperature plasmas, this represents a particular advantage.

[0016] The plasma-activated liquid can be understood as a liquid activated by the action of a reactive gas stream emerging from an atmospheric plasma source. In particular, the liquid can be directly exposed to an atmospheric plasma, such as an atmospheric plasma jet, i.e., a working gas that is at least partially still in a plasma state emerging from the plasma source. Alternatively, the liquid can also be exposed to a working gas that has emerged from the plasma source after the working gas has already recombined, i.e., is no longer in a plasma state. Such recombined working gases have been found to still contain sufficient reactive species, such as ozone or nitrogen oxides, which form relatively long-lived reactive species in water, such as hydroxyl radicals, hydrogen peroxide, nitric acid, or nitrous acid.

[0017] Thus, a plasma-activated liquid can be produced by exposing a liquid to the working gas leaking from an atmospheric plasma source.

[0018] This device can have more than two plasma sources, each of which provides a reactive gas stream by generating a plasma in a working gas, and the composition of each working gas is different from each other.

[0019] This device has an activation chamber for holding a volume of liquid and a plasma source for generating a reactive gas stream by means of a discharge in a working gas, and the plasma source is connected to the activation chamber in such a way that the reactive gas stream generated by the plasma source is introduced into the activation chamber. In this way, an initial liquid, such as liquid water or an aqueous solution, in the activation chamber can accumulate reactive species in itself by acting with the reactive gas stream, and in this way a plasma-activated liquid is produced.

[0020] Various embodiments of this method, device, and use are described below, and each of these embodiments is applied individually to this method, device, and use. In addition, the individual embodiments can be combined with each other.

[0021] In one embodiment, the plasma-activated liquid is produced by causing an initial liquid to act with a first reactive gas stream and a further reactive gas stream. In this way, several reactive gas streams generated by separate plasma sources can be made to react with each other in a predictable and controllable manner within the working liquid. Thus, a plasma-activated liquid having specific properties can be provided.

[0022] The starting liquid can be water, an aqueous solution, a solvent, an alcohol-containing solution, or the like.

[0023] In one embodiment, the starting liquid is acted upon separately with the first reactive gas stream and the further reactive gas stream. This ensures that the individual reactive gas streams do not react with each other before being introduced into the starting liquid. In addition, it can be achieved that the reaction of the components of the individual reactive gas streams takes place only within the working liquid.

[0024] In a corresponding embodiment, the working device is configured to act separately on the liquid present in the activation chamber with the first reactive gas stream and the further reactive gas stream.

[0025] Preferably, the first reactive gas stream and the further reactive gas stream are at least partially introduced into the starting liquid at different spatial positions simultaneously, so that spatially separated actions on the same starting liquid occur. 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 acted upon separately from the point of time.

[0026] Due to the separate actions of the starting liquid and the first reactive gas stream and the additional reactive gas stream, the acting device may be provided with a first acting element configured to act on the liquid present in the activation chamber with the first reactive gas stream, and an additional acting element configured to act on the liquid present in the activation chamber with the additional reactive gas stream. In this way, the separate actions of the starting liquid can be easily designed, and suitable acting parameters such as, for example, flow rate or flow velocity and time synchronization can be set.

[0027] In a further embodiment, the first reactive gas stream and the additional reactive gas stream are first mixed to form a common reactive gas stream, and then the starting liquid is acted on with this common reactive gas stream. In this way, the reaction of the components of the individual reactive gas streams can be caused in a target - defining manner before being introduced into the starting liquid.

[0028] In a further embodiment, a gas mixing device is connected upstream of the acting device, and this mixing device is configured to mix the first reactive gas stream and the additional reactive gas stream into a common reactive gas stream, and the acting device is configured to act on the liquid present in the activation chamber with the common reactive gas stream. The gas mixing device can be used to set mixing conditions such as, for example, the mixing ratio, mixing speed, or the like of the reactive gas streams. This enables the control of the reaction of the individual components of the first reactive gas stream and the additional reactive gas stream.

[0029] Preferably, the gas mixing device is advantageously arranged between the first plasma source and the acting device or between the additional plasma source and the acting device in the gas stream.

[0030] In a further embodiment, the acting device is configured to mix the first reactive gas stream and the additional reactive gas stream and to act the mixed reactive gas stream on the starting liquid. In this way, a separate gas mixing device can be eliminated and the overall device can be designed compactly.

[0031] In a further embodiment, the working device has a working element configured to act on a starting liquid present in the activation chamber and a mixture of a first reactive gas stream and a second reactive gas stream. If necessary, the working device can simplify its maintenance and the replacement of individual working elements by having a modular design.

[0032] In a further embodiment, the first reactive gas stream and a further reactive gas stream contact the starting liquid either separately by the working device or as a common reactive gas stream, and the working device includes a disk aerator which is a ventilation element made of a porous material.

[0033] In a corresponding embodiment, the ventilation device has a disk aerator which is a ventilation element made of a porous material.

[0034] The disk aerator typically has a gas-permeable membrane, such as a membrane having a large number, particularly hundreds or thousands, of small openings, through which the reactive gas stream enters the liquid in the form of small bubbles having a correspondingly large surface area with respect to volume, thereby interacting strongly with the liquid. By using a ventilation element made of a porous material, such as a porous ceramic having a large internal surface area, a similarly strong interaction is achieved.

[0035] A suitable production unit having a disk aerator is known, for example, from European Patent Application Publication No. 3 470 364 (A1).

[0036] p The plasma activation liquid is prepared by causing a first starting liquid to act on a first reactive gas stream to provide a first working liquid, causing a second starting liquid to act on a second reactive gas stream to provide a further working liquid, and obtaining the plasma activation liquid by mixing the first working liquid and the further working liquid. In this way, a plasma activation liquid having characteristics based on the composition of several working liquids can be provided.

[0037] The first starting liquid and other starting liquids can be of the same type, such as water for example.

[0038] This thing also provides the advantage that the plasma activation liquid can be made available with a time and / or spatial delay with respect to the generation of the reactive gas stream. For this purpose, for example, the first working liquid and a further working liquid can be stored separately from each other for a certain period and then mixed. For example, by separately storing or transporting a first working liquid having oxidation characteristics and a further working liquid having reduction characteristics and then mixing them at the place of use to react with each other, a plasma activation liquid having the characteristics of the reaction components of the individual working liquids can be provided.

[0039] In a further embodiment, the first working gas and / or a further working gas is a predefined industrial gas. In this way, the composition of the working gas and its reaction can also be controlled. In addition, since industrial gases are readily available on the market, the apparatus or method in this embodiment can be easily modeled, at least with respect to the supply of the working gas.

[0040] In a particular embodiment, the first working gas and / or a further working gas is, for example, the result of gas separation upstream of the individual plasma sources by means of a separation device or the like, and then this separation device supplies the working gas corresponding to the individual plasma sources.

[0041] Industrial gases are gases that are produced and used on an industrial scale. In particular, industrial gases have a high purity defined by standards, which is achieved by gas treatment. Such purity can be, for example, a maximum proportion of foreign gases on the order of 10 -6.0 or 1 ppm, for example. Industrial gases can be single-element gases or gas mixtures of these pure gases. Industrial gases are typically not gases extracted from natural deposits without further treatment.

[0042] In one embodiment, the first working gas and / or further working gases include one or more of a gas mixture of a species selected from the following list or a gas mixture of a predetermined composition. O2, N2, an inert gas such as Ar, CO2, Cl2, forming gas, N2 mixed with one or more inert gases, H2 mixed with one or more inert gases.

[0043] In a further embodiment, the first reactive gas stream is generated in the first working gas by means of an electric discharge. Alternatively or additionally, a further reactive gas stream is generated by means of an electric discharge in the further working gas. The electric discharge is a capacitively coupled discharge, a high-frequency arc-like discharge, a DC arc discharge, or a discharge generated by a microwave jet nozzle.

[0044] In a corresponding embodiment, the first plasma source and / or further plasma sources are configured to generate a plasma by means of an electric discharge in the working gas, the electric discharge being a capacitively coupled discharge, a high-frequency arc-like discharge, a DC arc discharge, or a discharge generated by a microwave jet nozzle.

[0045] In this way, plasma sources already available on the market can be used.

[0046] By providing or using a plasma source configured to generate a reactive gas stream by means of an arc-like discharge, in particular a high-frequency arc-like discharge, in the working gas, a high concentration of specific reactive species in the gas stream, in particular fully or partially ionized or excited atoms or molecules, can be generated.

[0047] In order to generate a reactive gas stream by means of a high-frequency arc-like discharge in the working gas, a plasma source having a conductive nozzle tube with a downstream nozzle opening for the appearance of the reactive gas stream during operation is preferably used, and it has a working gas inlet on the upstream side, the working gas inlet being connected to the nozzle opening via a flow path, an internal electrode being arranged in the flow path, and a high-frequency high voltage being applicable between the internal electrode and the nozzle tube.

[0048] For the operation of this arc-type plasma source, working gas is introduced into the working gas inlet, and a high-frequency high voltage is applied between the internal electrode and the nozzle tube, whereby an arc-like discharge is formed between the internal electrode and the nozzle tube, and by the interaction between the arc-like discharge and the working gas flow, the working gas is at least partially converted into a 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 having a voltage intensity in the range of 1 to 100 kV, preferably 1 to 50 kV, more preferably 10 to 50 kV, and a frequency of 1 to 300 kHz, particularly 1 to 100 kHz, preferably 10 to 100 kHz, more preferably 10 to 50 kHz is applied between the internal electrode and the nozzle tube.

[0049] Alternatively or additionally, a plasma source configured to generate a reactive gas flow by a dielectrically inhibited discharge in the working gas may be provided or used. By the dielectrically inhibited discharge, a very high concentration of specific reactive species, particularly ozone, can be generated in the gas flow. By using such a reactive gas flow to produce a plasma-activated liquid, hydroxyl radicals having a good sterilizing effect in the liquid can be formed.

[0050] To generate a reactive gas flow by a dielectrically inhibited discharge in the working gas, a plasma source having a conductive nozzle tube with a downstream nozzle opening for emerging the reactive gas flow during operation and an upstream working gas inlet connected to the nozzle opening via a flow path is preferably used. The flow path preferably extends at least partially between the nozzle tube and the DBD electrode, whereby a dielectric is disposed between the nozzle tube and the DBD electrode, and a high-frequency high voltage can be applied between the DBD electrode and the nozzle tube.

[0051] 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 prevents direct discharge between the DBD electrode and the nozzle tube, a dielectrically inhibited discharge occurs in the portion of the flow path extending between the DBD electrode and the nozzle tube. As a result, the working gas flow guided through the flow path is excited and / or enhanced by reactive species, and a reactive gas flow appears from the nozzle opening. Preferably, a high-frequency high voltage having a voltage in the range of 5 to 15 kV and a frequency in the range of 7.5 to 25 kHz, particularly 13 to 14 kHz, is applied between the DBD electrode and the nozzle tube.

[0052] For example, a DC arc discharge can be generated using a plasma spray nozzle or the like. In this case, the discharge is applied over a predetermined time window without being pulsed, and the temperature inside the working gas or in the immediate vicinity of the discharge is typically several thousand Kelvin.

[0053] In a further embodiment, a first working gas source is provided and configured to supply a first working gas to a first plasma source, and a further working gas source is provided and configured to supply a further working gas to a further plasma source, and the composition of the first working gas is different from the composition of the further working gas.

[0054] This means that not only can the parameters of the plasma source itself be individually set for each working gas, but also the composition of each working gas itself and the characteristics accordingly can be set. For example, a first working gas and another working gas that could react with each other if pre-mixed can be separately processed with plasma according to their respective unique characteristics.

[0055] Preferably, the first plasma source is connected to the first working gas source, and the further plasma source is connected to the further working gas source, so that the first working gas source and the further working gas source are separated from each other. In this way, the compositions of the first working gas and the further working gas can be easily controlled.

[0056] In a further embodiment, the apparatus has a control device configured to control the operation of the apparatus. In particular, the control device can have a memory with commands, and the apparatus is controlled by the execution of those commands in at least one microprocessor of the control device.

[0057] Further features and advantages of this method, apparatus, and use are shown in the description of the following embodiments, where the accompanying drawings are referred to.

Brief Description of the Drawings

[0058]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0059] FIG. 1 shows a schematic cross-sectional view of a plasma source 2 in the form of a plasma nozzle for generating a reactive gas flow 26 in the form of an atmospheric plasma jet by an arc-like discharge.

[0060] The plasma nozzle 2 has a metal nozzle tube 4 that tapers conically towards the nozzle opening 6. At the end of the nozzle tube 4 opposite the nozzle opening 6, the nozzle tube 4 has a swirler 8 with an inlet 10 for a gas flow, in particular a working gas such as air or nitrogen.

[0061] The intermediate wall 12 of the swirler 8 has a ring of holes 14 that are angled circumferentially, through which the gas flow is swirled. Thus, a gas flow in the form of a vortex 16 flows in the conical tapered portion downstream of the nozzle tube, and the core of this vortex 16 travels along the longitudinal axis of the nozzle tube. An internal electrode 18 is arranged at the center of the lower side of the intermediate wall 12 and projects coaxially into the nozzle tube in the direction of the tapered portion. The electrode 18 is electrically connected to the intermediate wall 12 and the other parts of the swirler 8. The swirler 8 is electrically insulated from the nozzle tube 4 by a ceramic or quartz glass tube 20. The high-frequency high voltage generated by the transformer 22 is applied to the electrode 18 via the swirler 8. A gas flow 23 is supplied to the inlet 10 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.

[0062] Here, the terms "arc", "arc discharge", or "arc-like discharge" are used as a description of the discharge phenomenon. This is because the discharge occurs in the form of an arc. In other places, the term "arc" is also used as a form of discharge for DC discharge with a certain voltage value. However, in this case, a high-frequency discharge in the form of an arc, that is, a high-frequency arc-like discharge, is mentioned.

[0063] However, due to the swirling flow of the working gas, this arc is guided to the vortex core on the axis of the nozzle tube 4, so it spreads only towards the wall of the nozzle tube 4 in the area of the nozzle opening 6. The working gas rotates at a high flow rate in the area of the vortex core, i.e., in the immediate vicinity of the arc 24, and is partially converted to a plasma state in order to come into close contact with the arc. Thus, an atmospheric plasma jet 26 emerges from the plasma nozzle 2 through the nozzle opening 6.

[0064] Figure 2 shows a schematic cross-sectional view of a further plasma source 32 in the form of a nozzle for generating a reactive gas flow by dielectrically impeded discharge, in perspective view.

[0065] The nozzle 32 has a metal nozzle tube 34, and at its upstream end 35, a distribution head 36 is arranged which has an inlet 37 for a gas flow 38, such as air, and an annular distribution channel 40. At the downstream end 42 of the nozzle tube 34 on the opposite side, an outlet nozzle 44 having a nozzle opening 46 is arranged, from which a reactive gas flow 38 strengthened by reactive species during operation emerges.

[0066] By extending a ceramic tube 48 from the distribution head 36 through the nozzle tube 34 into the outlet nozzle 44, an annular discharge channel 50 is made to extend from the distribution channel 40 between the nozzle tube 34 and the ceramic tube 48 to the outlet nozzle 44. Instead of the ceramic tube, a tube made of, for example, quartz glass, etc. could also be considered.

[0067] A tubular high-voltage electrode 52 made of metal is arranged inside the ceramic tube 48 and connected to a transformer 56 via a high-voltage cable 54, so that a high-frequency high voltage can be applied between the high-voltage electrode 52 and the grounded nozzle tube 34 acting as a counter electrode. Instead of the tubular high-voltage electrode 52, high-voltage electrodes of different shapes, such as in the form of a rounded metal sheet, etc., could also be considered.

[0068] An insulating plug 58 is disposed within the ceramic tube 48, which surrounds the high voltage electrode 52 and further prevents the working gas from flowing into the area of the high voltage electrode 52 or flowing out from the nozzle 32 through the ceramic tube 48. Further, a sealing ring 60 is inserted into the annular groove 62 of the distribution head 36, which seals the distribution head 36 with respect to the ceramic tube 48.

[0069] A coolant line 64 can be provided around the nozzle tube 34, and coolant can be sent through this coolant line 64 to cool the nozzle tube 34 during operation. As shown, the coolant line 64 can run around the nozzle tube 34, for example, in a helical shape.

[0070] During operation, by introducing a gas flow 38 into the distribution head 36 through the inlet 37, the gas flow 38 flows through the annular discharge channel 50.

[0071] By using a transformer 56 to apply a high frequency high voltage between the high voltage electrode 52 and the nozzle tube 34, a dielectrically inhibited discharge occurs in the discharge channel 50 in the area of the high voltage electrode 52, thereby generating reactive species, especially ozone, in the gas flow 38 flowing therethrough.

[0072] The reactive gas flow 38 enhanced by the reactive species exits from the nozzle opening 46.

[0073] Figure 3 shows a first embodiment of an apparatus 70 for plasma activation of a liquid. The apparatus 70 has a first plasma source 72, a second plasma source 74, and an activation chamber 76 for receiving a liquid 78, which is water in this case.

[0074] The first plasma source 72 is designed as a nozzle for generating a reactive gas flow by a dielectrically impeded discharge. The second plasma source 74 is designed as a plasma nozzle for generating a reactive gas flow in the form of an atmospheric plasma jet by an arc-like discharge. Each of the first plasma source 72 and the further plasma source 74 has gas inlets 80, 82 configured to supply working gases 94, 96 to the corresponding plasma sources 72, 74.

[0075] The activation chamber 76 has an actuator 84 having a first actuating element 86 and a second actuating element 88, both designed as disk diffusers. By the first actuating element 86 being in fluid connection with the first plasma source 72, the first reactive gas flow 90 emerging from the first plasma source 72 can enter the activation chamber 76 via the first actuating element 86. Similarly, by the second actuating element 88 being in fluid connection with the second plasma source 74, the second reactive gas flow 92 emerging from the second plasma source 74 can enter the activation chamber 76 via the second actuating element 88. The first actuating element 86 and the second actuating element 88 are designed and arranged separately from each other such that the first reactive gas flow 90 and the second reactive gas flow 92 first come into contact within the activation chamber 76.

[0076] The device schematically shown in FIG. 3 operates as follows. A first working gas flow 94 is supplied to the first plasma source 72 via the first gas inlet 80, and a second working gas flow 96 is supplied to the second plasma source 74 via the second gas inlet 82. This supply is carried out in parallel in a continuous flow from separate working gas sources not shown here, where the first working gas 94 is an industrial gas containing nitrogen and the second working gas 96 is an industrial gas containing oxygen.

[0077] The first plasma source 72 generates a dielectrically impeded discharge in a first working gas 94 containing nitrogen. As a result, the first working gas 94 becomes the first reactive gas stream 90 and is induced to flow from the first plasma source 72 to the first acting element 86. Thus, the first reactive gas stream 90 is introduced into the water 78 absorbed (aufgenommene, absorbed) by the activation chamber 76 as minute bubbles 98 through the porous structure of the first acting element 86 designed as a disk aerator.

[0078] In parallel with this, the second plasma source 74 generates an arc-like discharge in a second working gas 96 containing oxygen, and then the second working gas 96 is converted into the corresponding reactive gas stream 92 and sent to the second acting element 88. Thus, 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.

[0079] Within the activation chamber 76, the first reactive gas stream 90 and the second reactive gas stream 92 react with the water 78 and with each other to produce plasma-activated water.

[0080] FIG. 4 shows a schematic view of a second embodiment of an apparatus 100 for producing a plasma-activated liquid. Similar to FIG. 3, this apparatus 100 has a first plasma source 102, a second plasma source 104, and an activation chamber 106 for holding a liquid 108, which in this case is an alcohol-containing solvent, having an acting device 110. However, the apparatus in the embodiment of FIG. 4 is designed such that the acting device 110 is a single ventilation element made of a porous material fluidly connected to both the first plasma source 102 and the second plasma source 104. Further, both the first plasma source 102 and the second plasma source 104 are configured to generate a reactive gas stream by an arc-like discharge in the working gas.

[0081] During operation, the first working gas 112 is supplied to the first plasma source 102 through the respective gas inlets 116, 118, and the second working gas 114 is supplied to the second plasma source 104. 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. Then, the first reactive gas stream 120 and the second reactive gas stream 122 are sent in parallel and simultaneously to the actuator 108, where they are introduced into the alcohol-containing solvent 110 in the activation chamber 106.

[0082] Figure 5 shows a schematic view of a third embodiment of an apparatus 130 for producing a plasma-activated liquid. Again, a first plasma source 132, a second plasma source 134, and an activation chamber 136 having a liquid 138 are shown. The first plasma source 132 and the second plasma source 134 are both designed to generate a reactive gas stream by a dielectrically impeded discharge in the working gas, and by each having a gas inlet 140, 142, they are separated from each other. In addition, the first plasma source 102 has a first gas outlet 144 fluidly connected to a gas mixing device 146. Similarly, the second plasma source 134 is provided with a second gas outlet 148 fluidly connected to the gas mixing device 146.

[0083] The gas mixing device 146 is then fluidly connected to the actuator 150 of the activation chamber 136. Thus, the gas mixing device 146 is located upstream of the actuator 150 in the gas stream. The actuator 150 is designed as a disk aerator.

[0084] For the plasma activation of the liquid 138 received in the activation chamber, working gases 152, 154 are supplied to each of the first plasma source 132 and the second plasma source 134, where the compositions of the respective working gases 152, 154 are different. The first plasma source 132 and the second plasma source 134 each generate a plasma in parallel in the first working gas 152 and the second working gas 154, thereby also generating a first reactive gas stream 156 and a second reactive gas stream 158, each of which is supplied to the gas mixing device 146.

[0085] In the gas mixing device 146, the first reactive gas stream 156 and the second reactive gas stream 158 are both mixed and then sent as a common reactive gas stream 160 to the working device 150. There, the common reactive gas stream 160 contacts the liquid 138 in the activation chamber 136 and is mixed with the liquid 138 to provide a plasma-activated liquid. Thus, in this method, 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 the initial liquid is acted upon by the common reactive gas stream 160.

[0086] FIG. 6 shows a schematic view of a fourth embodiment of an apparatus 170 for producing a plasma-activated liquid. A first plasma source 172 and a second plasma source 174 are provided, both configured to generate reactive gas streams 176, 178 by arc-like discharge in the working gas. Further, a first activation chamber 180 having a first liquid 182 and a second activation chamber 184 having a second liquid 186 are provided, and each activation chamber 180, 182 has a working device 188, 190.

[0087] The first plasma source 172 is in fluid connection with the first activation chamber 180 or the working device 188 of the first activation chamber 180. In addition, the second plasma source 174 is in fluid connection with the second activation chamber 184 or the working device 190 of the second activation chamber 184.

[0088] The apparatus 170 further includes a mixing vessel 192 fluidly connected to a first activation chamber 180 and a second activation chamber 184.

[0089] To provide a fluid to which plasma is applied, a first working gas 194 is supplied to a first plasma source 172, and in parallel, a second working gas 196 is supplied to a second plasma source 174. The first plasma source 172 generates plasma in the first working gas 194, and the resulting first reactive gas stream 176 flows from the first plasma source 172 to the actuator 188 and is mixed with the liquid 182 in the first activation chamber 180. Additionally and simultaneously, the second plasma source 174 generates a second reactive gas stream 178 by means of a discharge in the second working gas 196, and the second reactive gas stream 178 is sent to the actuator 190 of the second activation chamber 184 and supplied to the liquid 186 present in the second activation chamber 184.

[0090] Thus, in parallel, a first liquid 198 acted upon by the first reactive gas stream in the first activation chamber 180 is provided, and a second liquid 200 acted upon by the second reactive gas stream in the second activation chamber 183 is provided. In a further method step, the first working liquid 198 and the second working liquid 200 are sent to the mixing vessel 192 where they are mixed to form a plasma-activated liquid 202.

[0091] It is also conceivable to provide each of the three liquids 182, 186, and 202 in a container, act on only two of them with a reactive gas stream, and then mix these two acted-upon liquids with a third liquid.

Claims

1. A method for producing a plasma-activated liquid (202), comprising: - A first working gas (94, 112, 152, 194) is supplied to a first plasma source (72, 102, 132, 172), and the first plasma source (72, 102, 132, 172) generates plasma in the first working gas (94, 112, 152, 194), thereby providing a first reactive gas stream (90, 120, 156, 176); - A further working gas (96, 114, 154, 196) is supplied to a further plasma source (74, 104, 134, 174), and the further plasma source (74, 104, 134, 174) generates plasma in the further working gas (96, 114, 154, 196), thereby providing a further reactive gas stream (92, 122, 158, 178); - Using the first reactive gas stream and the further reactive gas stream (90, 120, 156, 176, 92, 122, 158, 178) to produce a plasma-activated liquid (202); - The composition of the first working gas (94, 112, 152, 194) is different from the composition of the further working gas (96, 114, 154, 196). A method.

2. The method according to claim 1, wherein the plasma-activated liquid (202) is produced by reacting a starting liquid (78, 110, 138, 182, 186) with the first reactive gas stream (90, 120, 156, 176) and the further reactive gas stream (92, 122, 158, 178).

3. The method according to claim 2, characterized in that the starting liquid (78, 110, 138, 182, 186) is reacted with the first reactive gas stream (90, 120, 156, 176) and the further reactive gas stream (92, 122, 158, 178) separately.

4. The 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 reacted with the common reactive gas stream (160).

5. The method according to claim 1, wherein the plasma activation liquid (202) is produced by causing a first starting liquid (182) to act on the first reactive gas stream (176) to provide a first working liquid (198), causing a second starting liquid (186) to act on the second reactive gas stream (178) to provide a further working liquid (200), and obtaining the plasma activation liquid (202) by mixing the first working liquid (198) and the further working liquid (200).

6. 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 industrial gas.

7. - The first reactive gas stream (90, 120, 156, 176) is produced by a discharge in the first working gas (94, 112, 152, 194), and / or - The further reactive gas stream (92, 122, 158, 178) is produced by a discharge in the further working gas (96, 114, 154, 196), - The discharge is a dielectrically impeded discharge, a high-frequency arc-like discharge, a DC arc discharge, or a discharge generated by a microwave jet nozzle. The method according to any one of claims 1 to 6.

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) contact the starting liquids (78, 110, 138, 182, 186) separately or as a common reactive gas stream (160) by means of an action device (84, 108, 150, 188, 190), and the action device (84, 108, 150, 188, 190) includes a disk aerator which is a ventilation element made of a porous material.

9. An apparatus (70, 100, 130, 170) for producing a plasma activation liquid (202), - The first plasma source (72, 102, 132, 172) configured to generate plasma in a first working gas (94, 112, 152, 194) supplied to the first plasma source (72, 102, 132, 172) so as to provide a first reactive gas stream (90, 120, 156, 176), - A further plasma source (74, 104, 134, 174) supplied with a further working gas (96, 114, 154, 196) so as to generate plasma in the further working gas in which a further reactive gas flow (92, 122, 158, 178) is provided, - An activation chamber (76, 106, 136, 180, 184) for receiving a liquid, - An acting device (84, 108, 150, 188, 190) configured to act on the liquid (78, 110, 138, 182, 186) present in the activation chamber (76, 106, 136, 180, 184) with the first reactive gas flow (90, 120, 156, 176) and the second reactive gas flow (92, 122, 158, 178) The device (70, 100, 130, 170) comprising.

10. The device (70, 100, 130, 170) according to claim 9, characterized in that the acting device (84, 108, 150, 188, 190) is configured to act separately on the liquid (78, 110, 138, 182, 186) present in the activation chamber (76, 106, 136, 180, 184) with the first reactive gas flow (90, 120, 156, 176) and the second reactive gas flow (92, 122, 158, 178).

11. - A gas mixing device (146) is connected upstream of the acting device (150), and the mixing device is configured to mix the first reactive gas flow (156) and the second reactive gas flow (158) into a common reactive gas flow (160), - The acting device (150) is configured to act on the liquid (138) present in the activation chamber (136) with the common reactive gas flow (160) The device (70, 100, 130, 170) according to claim 9, characterized by this.

12. - 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), - 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), - The composition of the first working gas (94, 112, 152, 194) is different from the composition of the additional working gas (96, 114, 154, 196). The apparatus (70, 100, 130, 170) according to any one of claims 9 to 11, characterized by the above.

13. - The first plasma source (72, 102, 132, 172) and / or the additional plasma source (74, 104, 134, 174) are configured to generate plasma by discharge in the working gas (94, 112, 152, 194, 96, 114, 154, 196). - The discharge is a capacitively coupled discharge, a high-frequency arc-like discharge, a DC arc discharge, or a discharge generated by a microwave jet nozzle. The apparatus (70, 100, 130, 170) according to any one of claims 9 to 12, characterized by the above.

14. The apparatus (70, 100, 130, 170) according to any one of claims 9 to 13, characterized in that the working device (84, 108, 150, 188, 190) has a disk aerator which is a ventilation element made of a porous material.

15. Use of the apparatus (70, 100, 130, 170) according to any one of claims 9 to 14 for producing a plasma-activated liquid, in particular according to the method according to any one of claims 1 to 8.

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