WO2012069632A1

WO2012069632A1 - Method and apparatus for preparing or processing a process material, which is surrounded by a gaseous medium, with the aid of electrical discharges

Info

Publication number: WO2012069632A1
Application number: PCT/EP2011/071031
Authority: WO
Inventors: Carsten Leu; Stefan Gossel
Original assignee: Technische Universität Ilmenau
Priority date: 2010-11-25
Filing date: 2011-11-25
Publication date: 2012-05-31
Also published as: DE102010052723A1; EP2643910A1; DE102010052723B4

Abstract

The invention relates to a method and to an apparatus for preparing or processing process material, in particular biological process material. The present invention provides an improved and more energy-efficient method and an associated apparatus for destroying or disintegrating the surface and/or the cells of biomasses in the broadest sense (process material) for more rapid liberation and more effective recovery of the contents. According to the invention, the process material is exposed to channel-like, low-energy electrical gas discharges or physical plasma. Efficient disintegration or destruction of the surface/cells is achieved on account of the internal discharge pressure. In the process, the electrical gas discharges or physical plasma are caused by a high voltage with a high frequency, this voltage being generated by an apparatus by the preferably resonant magnetic coupling of at least two electrical resonant circuits.

Description

The present invention relates to a method and a device for preparing or processing a process material enclosed by a gaseous medium by means of electrical discharges

Apparatus for preparing or processing biological cells or organic materials (process material), in particular a method and apparatus for destroying or digesting the surface and / or cells of biomass in the broadest sense (process material).

For a long time, a ^large number of methods and devices for processing organic or inorganic substances have been known from the prior art.

For example, No. 4,838,154 A discloses a process for the pasteurization of liquid foods, in which the liquid foods to be pasteurized are prepared by means of e.g. flow tubular electrode assembly and exposed there pulsed electrical fields. The pasteurization is carried out by the action of the pulsed electric fields whose field strengths are 5 - 12 kV / cm and whose pulse duration is 5 - 100 is. The liquid foods to be pasteurized are each exposed to 2 to 5 pulses. The electric fields used are generated here by the discharge of high-voltage capacitors on the electrode assembly.

From the document DE 195 342 32 C2 a method for comminution and fragmentation of solids is known. The

Shredding of the solids takes place here by the rapid discharge of an electrical energy storage. The solid ^¬ body or solid fragments are in one or only low-conductivity process fluid, such as water, a high voltage insulating liquid, a water-glycol or water-alcohol mixture immersed, in which a system of high voltage and grounded electrodes protrudes. As electrical energy storage is a capacitor which is discharged in a discharge pulse-shaped. It follows a discharge. The solids are exploded by shock waves caused by internal discharges.

With the documents DE 10 144 486 C1 and WO 03/02244 AI a method and a reactor for non-thermal digestion and pasteurization of organic process material by electroporation was presented. The process is for the production of food or food components, wherein the process material is flowed in or with a process liquid / transport liquid through a tunnel-shaped reactor and thereby exposed to pulsed electric fields. For this purpose, electrode groups are arranged in the tunnel-shaped reactor, which are subjected to pulse-like high voltage. The fields are generated in that the electrodes or electrode group on high-voltage cable and a switch or spark gap located in the tunnel-shaped reactor with a round or polygonal or at least quadrangular cross-section of dielectric material are acted upon by a Marx generator with a high voltage. By means of the electrode groups alternately pulsed electric fields of various direction and strength are generated.

With DE 10 144 479 C2 an electroporation reactor for the continuous processing of lumpy products was known, in which, however, the process material is transported by a process liquid and there is subjected to high voltage. The reactor consists of a circular-cylindrical drum, similar to a water wheel, and conveys the lumpy process material through the process liquid, which is located in the lower half of the drum. The electrodes for loading are in the deepest area.

From DE 10 2005 046 413 AI another method and associated circuitry for the electroporation of agricultural products is known. Also in this method, high pulsed electric field strengths are needed for cell disruption. For this purpose, a multi-stage, triggerable Marx generator with a long service life is presented. The disadvantage of such circuits is clearly seen in the large flowing pulsed (discharge) currents and the associated energy conversion, ie the heating (up to the combustion) of the process material.

In all hitherto considered writings the process material is, in the cases in foods or food components ^¬ or vegetable and animal fluids or non-conductive solids digestion or a machining process applied in liquid form or as disperse phase of a dispersion. In any case, the digestion process is bound to a liquid which has direct contact with the electrodes. There is, for example, water is used as Prozessflüs ^¬ fluid.

The digestion or the preparation of the process material takes place in all known methods by the application of a high electric field strength or by the current flow through the process material to be processed (liquid or dispersion). The described pulse-like stress and thus field strength loads of the dispersion, ie the mixture of process material and process liquid, lead accordingly high dielectric losses in the dispersion itself, which is seen as a significant disadvantage of all these methods.

Furthermore, the transport of a dispersion through a reactor is bound to closed tubular systems or it must be ensured that the process fluid always remains at the desired locations in the reactor. This is not only very complicated and impractical, but the use of pumps and other technology also requires an additional energy consumption.

The high electrical field strength is generated in the known procedural ^¬ ren and arrangements by the discharge of high-voltage capacitors, for example by the use of Marx generators. Such systems are very voluminous and massive and difficult to handle in relation to a possible application. Another disadvantage is that during discharge in such systems, a current in the kilo-ampere range flows through the process material, which results in a corresponding energy turnover in the process material and thus heating of the process material. Furthermore, charging and discharging of capacitors are lossy and always tied to time constants. The recharging of the capacitors after their discharge requires a certain amount of time, especially with large capacities as energy storage, as used in Marx generators.

In addition to the already mentioned methods and devices for processing organic or inorganic substances, there are solutions in which no liquids or dispersions are used. For example, DE 199 57 775 C1 proposes a method for modifying wood surfaces by electrical discharges at atmospheric pressure, in which an electrode is arranged opposite the wood surface to be modified and between this electrode and the wood surface a dielectric layer. A alternating ^high voltage is applied to the electrode, whereby a "dielectrically impeded discharge" or "silent electrical discharge" (dielectric electric discharge) is formed between the dielectric layer and the wood surface to be modified. The alternating high voltage may also be high voltage pulses whose distance is greater than their duration. However, the "dielectrically impeded discharge" described here is a form of corona discharge.The process presented is for cleaning the wood surface (removal of loose components), improving the gluing or coating properties of the wood surface (improving adhesion), preserving and fading the wood surface used by the action of ozone. the-described ^¬ nen "dielectric barrier discharges" thus act only on the surface of the wood.

A similar method is described prinzipiell 162 86 88 BL in the EP, enthal- tende biologische Materialien be treated with a erzeugtem by a Gasentla ^¬ dung plasma in the living cells. However, the plasma generated here causes the killing of microorganisms, for example, in tooth decay of a tooth, and is produced in a much smaller area. For this purpose, the oxidative effect of resulting free oxygen or of

Used ozone. The gas discharge or the generated plasma is therefore a discharge, which can also be classified as a corona discharge. The procedure is to place an electrode at a small distance above the surface to be treated, the electrode being encased in a solid solid state dielectric. Similar methods are also known from WO 2004/023927 AI or DE 10 2006 020 484 AI and EP 202 40 80 Bl, in each of which a dielectrically impeded gas discharge is generated, which leads to a uniform formation of the plasma.

With these known methods is basically no destruction of bulk or seed or the surface to be treated intended and not feasible. Another aspect of the invention relates to the generation of high-frequency oscillations or high-frequency high voltages by resonant coupling of electrical resonant circuits. Here, too, are known from the prior art, numerous solutions are known (e.g., DE 1,034,766 A, DE 1,564,166 B, DE 2410060 Al, DE 8807090 Ul, DE 3923694 Cl, Cl DE 4,235,766, DE 4,438,533 Al and DE 19802662 Al).

In DE 19802662A1, e.g. describes a method for producing composite films, which is characterized in that corona discharges take the form of short individual pulses having a frequency of 10 ... 30 kHz, a pulse width of less than 30 με and a rise time of less than 5 is , The corona discharge occurs between two rod-shaped electrodes, each having an electrically conductive core and a dielectric sheath.

So far, arrangements, circuit variants and systems are known, for example, the examination, processing and processing of foils or very thin materials. These circuits for generating electrical gas discharges generate only corona discharges. These discharges are significantly too short and not enough pronounced to reach biomass digestion.

In the known arrangements, circuit variants and systems, a first electrical resonant circuit (or primary circuit) is fed for example with a high-frequency current. The disadvantage here is that additionally consuming

Devices or circuits are needed to provide this high-frequency power available. The performance of such devices or circuits are very limited even in the current state of the art. Other circuit variants use a DC voltage source for the power supply. The Erzeu ^¬ supply of individual pulses or vibrations of similar processes in a primary circuit then takes place by means of power electronic devices which a flowing stream zerha ^¬ CKEN. The current carrying capacity and the dielectric strength of such power electronic switches are also very limited. The opening and closing of these power electronic switches must be clocked by an additional control circuit, which unnecessarily complicates the circuitry.

Object of the present invention is therefore to overcome the disadvantages of the prior art and to provide an improved and more energy efficient method and an associated apparatus for preparing ^¬ or processing of biological cells or of organic materials (process material). In particular, it is the object, a method and apparatus for destruction or for direct digestion, ie without conversion to a disperse or liquid phase, the Surface and / or the cells of biomass in the broadest sense (process material) to provide faster recycling of the ingredients, with a direct contact between process material and the high voltage electrodes used is not required, but not cumbersome.

According to the invention this object is achieved by a method having the features of the first claim and by a device having the features of the eighth claim.

According to the invention do not act as in previously known methods, the field strength, but channel-shaped electric Gasentladun ^¬ gene, which can also be characterized as physical plasmas and represent a subset of the comprehensive term physika ^¬ metallic plasmas, on the process material a which is penetrated partially or completely, which leads to an opening of the surface structure and the biological cells of the process material and thus to the release of the ingredients of the cells. For this it is of particular importance that a low-energy discharge is generated, by which is meant, however, that a mechanical disruption of the cell ^¬ surface of the biological cells is achieved by the discharge is caused no thermal or chemical conversion or destruction of the cell itself , so the process material is not overheated. Rather, the disruption of the cells is caused by the internal discharge pressure. In this case, the electrical gas discharges or physical plasmas are caused by a high-frequency high-frequency voltage which, in a particularly preferred embodiment, is generated by a device through the resonant or nearly resonant magnetic coupling of at least two electrical oscillating circuits. The process material is exposed according to the invention the electrical discha ^¬ gene, the light between at least two electrodes by being transported through the discharge space. In an alternative embodiment, one of the electrodes can also be moved relative to the process material.

The electrical discharge is low energy, preferably repetitive electrical gas discharges, the channel-shaped form itself (e.g., spark, streamer, Leader discharges or breakdown processes) and which are generated by applying a high frequency, repetitive high voltage to at least one of the electrodes.

The shape and size of the high-voltage electrodes are adapted to the processing of the process material, the formation and spatial distribution of the electrical gas discharges and the vote of the second electrical resonant circuit of the device for performing the method or adaptable depending on the application. According to the invention a plurality of desired parallel gas discharge channels is produced which the be digested process material (biomass) is fully or at ^¬ least partially penetrate (physically hole) and thereby break the cell structure and destroy, so that the contents of the cells can escape (lighter).

The inventive method the destruction or decomposition of the surface and / or the cells of the process ^¬ good is achieved, without this resulting in such a high Ener ^¬ gieeintrag in the process material, which would result in a thermal conversion of the process good result. The method ^according to the invention is characterized by versatile and flexible application possibilities, the gas discharges being connected with respect to their geometry and their energy content to the sequent process material by the skilled person can easily be adapted in order to achieve the aim of the invention, namely on the one hand due to the cell penetrating charge to achieve the digestion of the cell surface and on the other hand, thermal and chemical transformations largely to vermei ^¬ since such conversions of the actual use of the process material (use as biomass, extraction of biological ^¬ rule fabrics, etc.) would reluctantly. The inventive method is also particularly easy to perform and adapt, because the processed material to be processed has only very little repercussions on the respective device and the electrical parameters of the Aufschluction process itself (ie the gas discharges).

With an inventive treatment of biological process goods to reach the rapid release and effec ^¬ tivere utilization of the ingredients. The invention can eg for more efficient bioenergy production, for industrial purposes in sugar production, bioethanol production, oil extraction, recovery of essential oils or starch, for the pretreatment of plants or parts of plants (eg drying for the spice, tea or herbal production) or for the digestion animal cells are used for the purpose of substance separation or for further processing or for the release or penetration of substances.

Another advantage of the method according to the invention is that a significant and sustainable opening of the biological cells of the process material is already achieved by the low-energy but spatially extended, channel-shaped gas discharges, but the energy injected into the process can be kept very low and thus no need of Providing large energy storage such as For example, large and massive Hochspannungskondensa ^¬ tors and thus the overall energy balance, for example, in the application of the method for bioenergy production can be significantly improved.

At the end of the process of the invention the process is well ^¬ conveyed through the discharge space between the high voltage electrode assembly and the high voltage electrode ^arrangement or at least one of the electrodes to be moved over the process material. This generates a relative movement between the process material and at least one of the electrodes. In the effective range of the high-voltage electrode arrangement, electrical gas discharges or physical plasmas strike the surface of the process material to be disrupted and partially or completely penetrate the process material to be processed, which leads to an opening of the surface structure and the biological cells and thus to the release of the ingredients of the cells. The electrical gas discharges or physical plasmas lead to mechanical destruction but not to thermal or chemical transformations of the process material. Preferably, high frequency (1 / T ₀ ) repetitive gas discharges are generated from a few to a few hundred kilohertz and a repetition rate (1 / T _W ) of from several tens to several hundreds of hundreds (see Fig. 9) with a limited spatial spread; which are to be classified as channel-shaped discharges, for example spark, streamer, leader discharges or breakdown processes.

Preferred further embodiments of the method according to the invention are specified in the patent claims 2 to 7.

To implement the method, a device according to the invention is proposed, the electrical gas discharges or generate physical plasmas that cause the described digestion of biomass, with the necessary characteristics or necessary electrical parameters, the biomass or process material with their electrical and dielectric properties is part of the electrical circuit or the electrical device, but none or has very little effect on the electrical parameters of the device. The inventive apparatus for digestion of a process ^¬ good comprises a first and a second electrode between which a discharge space is formed. A first and a second electrical resonant circuit are magnetically coupled to each other and operate in resonance or near resonance to produce clear at least one of a repeating Elect ^¬ high voltage. The apparatus further comprises a means for moving the process material, or for moving Minim ^¬ least one of the high voltage electrodes. The advantages of the device according to the invention can be seen especially in the fact that a preferably high-frequency high tension ^¬ voltage is generated, the electric gas discharges or physical plasmas generated predetermined characteristic and thereby reacted as little energy as possible to avoid thermal conversion process in the process material largely.

The device is spatially small and flexible decor with ^¬ tet, for example, to ensure the integration of the device in reactors of any shape and size. Conveniently, the device comprises at least two electrical resonant circuits that are magnetically coupled together.

In contrast to already known arrangements for generating electrical discharges, the power supply of the device according to the invention is primarily a mains frequency AC voltage or even when needed a DC voltage usable, which allows flexible and network and transnational use of the device and the method. With the device, an effective processing of process material of various kinds is possible with electrical

Gas discharges or physical plasmas, the electrode distances of preferably up to 100 cm, more preferably overcome up to 50 cm. In a preferred embodiment, the first comprises

Oscillating circuit, a first inductance, a first capacitance and a passive switching element for opening and closing the first resonant circuit. As a switching element in the first resonant circuit is a passive switch element which independently closes the first resonant circuit to allow vibration with his Eigenf ^¬ frequency, and this then also opens again automatically to ensure recharging of the energy storage. Power electronic components or complex additional circuits in the form of control circuits or frequency generators or other types of clock omitted here advantageously.

Preferred further embodiments of the device according to the invention are specified in the claims 9 to 15.

Further details and advantages of the invention will become apparent from the following description part, in which the invention with reference to the accompanying drawings, in which the same reference numerals designate like or similar parts throughout the figures, is explained in more detail.

Show it: 1 shows a schematic representation of a high voltage ^¬ electrode arrangement of a first embodiment of the device according to the invention;

2 shows a schematic representation of a high-voltage ^¬ electrode arrangement of a second embodiment of the device according to the invention;

3 shows a schematic representation of a high-voltage ^¬ electrode arrangement of a third embodiment of the device according to the invention;

4 shows a schematic representation of a high-voltage ^¬ electrode arrangement of a fourth embodiment of the device according to the invention;

5 shows a first preferred embodiment of a high-voltage electrode;

6 shows a second preferred embodiment of a high-voltage electrode;

Fig. 7: a schematic representation of a preferred embodiment of the device according to the invention;

8 shows a variant of the magnetic coupling of two electrical oscillating circuits for generating a repetitive high voltage;

9: a schematic representation of the time course of the high voltage generated according to the invention.

1 shows a schematic representation of a high-voltage electrode arrangement in a preferred embodiment of the device according to the invention. The device comprises a first high voltage electrode 1 and a second high voltage Nunging electrode 2. Between the high voltage electrodes 1, 2, a discharge space 3 is formed. The electrode shape, the distance, the dielectic in the discharge space and the applied high voltage are chosen so that a large number of desired, parallel, low-energy, repetitive, electrical gas discharges or physical plasmas between the at least two high voltage electrodes 1, 2 arise. In the discharge space 3 is during the implementation of the method, a layered or mixed dielectric, which includes a aufzuschließendes or to be treated process material 4 and the process material 4 surrounding gas, such as air, CO ₂ , ₂ . Between the high-voltage electrodes, an electrically insulating gas path is formed as the discharge space 3 to build up a suitable high voltage and to ignite the electrical gas discharges or physical plasmas with the required discharge characteristic. The skilled person can select the appropriate parameters based on his knowledge of discharge processes, always under the premise to achieve the digestion of the process material and to avoid its thermal transformation. Due to the low-energy but spatially extended, channel-shaped gas discharges, a significant and sustainable opening of the biological cells of the process material is achieved, but the energy injected into the process can be kept very low. Thus, there is no need to provide large energy storage such as large and massive high voltage capacitors and thus the overall energy balance can be significantly improved, for example, in the application of the method for bioenergy production.

For the digestion of the process material 4 according to the invention, the latter is treated with a residence time or a temperature to be determined for the process material to be digested Processually tuned throughput, so for example with appropriate conveying or throughput speed, by the high voltage electrode assembly 1, 2, moves or at least one of the high voltage electrodes is moved away with entspre ^¬ chender speed on the process material, the electrical gas discharges or physical plasmas ignite between the high voltage electrodes ,

A conveying device, the illustrated embodiment of a conveyor or conveyor belt 5, is arranged in the discharge space 3. In alternative embodiments, the conveyor may also be a turntable or other suitable device. A conveying speed is adjustable by a drive of this conveyor. In the embodiment shown in FIG. 1, the conveying device is made of a dielectric material. The second high-voltage electrode 2 is arranged directly below the conveyor belt 5.

In the high-voltage electrode arrangement represented in FIG. 2, the conveyor belt 5 itself consists of an electrically highly conductive material and thereby simultaneously forms the second high-voltage electrode 2 itself.

Another preferred high voltage electrode arrangement is shown in FIG. In this embodiment, the delivery of the process material 4 through the high-voltage electrical ^¬ denanordnung 1, 2 takes place by exploiting the gravity of the process material by falling of the process material along a fall distance. This imple mentation form has the advantage that no further energy input is required for the promotion of the process material 4 and there is a good mixing of the process material 4 with the air or the surrounding gas. In the embodiment of the high-voltage electrode arrangement shown in FIG. 4, the process material 4 is moved on an inclined plane 6 as a conveying device through the high-voltage electrode arrangement by utilizing the weight of the process material 4 or the process material moves by sliding itself. Throughput speed of the process material 4 to vary by the device according to the invention, the inclination angle of the inclined plane 6 can be vari- iert. The inclined plane 6 consists in the illustrated

From a guide shape of an electrically good conductive material and at the same time forms the second high-voltage electrode 2. In a modified imple mentation form, the inclined plane 6 is made of a dielectric material and is used only lent to promote the process material. Then, the second high-voltage electrode 2 is selbstverständ ^¬ Lich intrinsically ^¬ constantly to dispose accordingly.

Preferably, at least the second high-voltage electrode 2 is designed as a ground or reference electrode. At least the first high-voltage electrode 1, a high-frequency, repe ^¬ tierende high voltage (see Fig. 9) is applied, so that between the two high-voltage electrodes 1, 2 form electrical gas discharges or physical plasmas with the discharge characteristics described above. At least one of the high-voltage electrodes 1, 2 can also be a component of the conveying device.

The shape and spatial extent of the high voltage electrodes 1, 2 is crucial for the characteristic and the spatial

Distribution of electrical gas discharges or physical plasmas and thus for the effectiveness of the process and must on the process material 4 and the flow rate of the Process good 4 be tuned. Opposing large ^¬ flat, planar electrodes with a smooth surface call a relatively homogeneous electric field produced, causing a spatially fine distribution of the electrical gas discharges at the OF INVENTION ^¬ to the invention method, wherein the location of the ignition of the electrical gas discharge is essentially determined by the process material itself , High-voltage electrodes with opposing large-area, planar electrodes, for example plate-shaped electrodes, cylindrical electrodes or spherical electrodes with a sufficiently large diameter are thus advantageous for the digestion of different process material.

In addition, a spatially greatly limited discharge space can be generated with tip or ball electrodes with small diameters, but the location of the discharge ignition is clearly defined. With such an electrode can successful ^¬ Lich caused a strong inhomogeneous electrical field and the location of the ignition of the electrical gas discharge can be accurately determined.

With those shown in Figs. 5 and 6, high-voltage electrode arrangements, it is possible to use a flat and spatially extended exposure of the process material, so a multi ^¬ desired number, parallel gas discharge channels to produce. The illustrated electrode arrangements combine the

Advantages of homogeneous and inhomogeneous arrangements.

According to FIGS. 5 and 6, tip electrodes 8 or ball electrodes 9 having the required radius of curvature are arranged on a conductive base plate 7. Thus can be generated over a defined area discha ^¬ gen with the desired characteristics. With such electrode arrangements, it is thus possible to generate a multiplicity of parallel gas discharges. possible. Roden ^¬ using these comb or Bürstenelekt manages to pressurize the process material with a spatially defined, distributed electrical gas discharge channels or to penetrate. In order to achieve a desired discharge ignition and discharge distribution and thus optimum processing of different types of process material, various electrode geometries can be combined as desired. For example, individual ball or tip electrodes can in turn face individual ball or tip electrodes or even large-area, planar electrodes or comb or brush electrodes, resulting in a spatially narrow discharge space. Likewise, combinations of large-area, flat electrodes and comb or brush electrodes are possible, whereby a spatially extended discharge space can be generated.

A schematic representation of a preferred embodiment of the device ^{according to} the invention is shown in FIG. A device for generating the repetitive high voltage with preferably high frequency in this case comprises a first electrical resonant circuit 10 and a second electrical resonant circuit 11, which are magnetically coupled together. The magnetic coupling can be made loose or solid. In the illustrated embodiment, an inductance or coil 12 of the first resonant circuit 10 coaxially surrounds one

Inductance or coil 13 of the second resonant circuit 11. In this case, the inductance 13 of the second resonant circuit 11 is penetrated by the magnetic field of the inductance 12 of the first resonant circuit 10. The magnetic coupling can be adjusted to one another via the enclosed surface and / or the distance between the two coils 12, 13. However, the magnetic coupling can also be realized in that the inductance of a first resonant circuit of a primary coil 14 and the inductance of the second resonant circuit ^{¬ are} formed by a secondary coil 15 of a Hochspannungsstrans- formator 16, as shown in Fig. 8. The high-voltage transformer 16 is with or without magnetic material, such as ferrite or iron, out ^¬ leads. In addition to the first inductance 12, the first oscillating circuit 10 comprises at least one capacitance 17 and a switching element 18 for closing and opening the first electrical oscillating circuit 10. The switching element 18 is preferably formed by a spark gap and has the property of reaching the first oscillating circuit 10 after reaching a certain charging voltage of the first capacitor 17 to close automatically, the charging voltage and the capacitance 17 determine the energy input into the first resonant circuit 10. After closing the switching element 18, so for example after the ignition of the spark gap, takes place in the first resonant circuit 10, an electrical oscillation with the natural frequency (1 / T ₀ ) of this resonant circuit instead. The natural frequency

f ¹

/ ^{0 =} / is determined by the first inductance 12 and the first capacitance 17 of the first resonant circuit 10. The

Elements L and C are therefore selected so that a high-frequency vibration ^¬ with the desired frequency is produced. The resonant circuit dimensioning presents no problems to the person skilled in the art. Compared to other methods or circuits is advantageous that no vibrations or pulses must be impressed by external excitation here. The first resonant circuit 10 generates oscillations with its natural frequency fo, without additional elements or without external impulse. The Switching element 18 opens after the decay of the electrical oscillation, the first resonant circuit 10 independently, for example ^¬ by reconsolidation of a spark gap.

By the already described magnetic coupling of the first resonant circuit 10 with at least the second resonant circuit 11, the vibration is transmitted to the second resonant circuit 11 by transmitting the magnetic energy of the coils 12, 13, whereby the second resonant circuit 11 also to an electrical ^¬ oscillation with his Natural frequency fi is excited and between the high voltage electrodes 1, 2, a high-frequency repetitive high voltage ui (see Fig. 9) is formed.

In order to achieve the most energy-efficient excitation of the second or further oscillating circuits, the principle of resonance is used according to the invention, ie the natural frequency of the second or further oscillating circuits must correspond as closely as possible to the natural frequency of the first, exciting oscillating circuit.

The second or further oscillating circuits are formed by the second inductance 13 of the second oscillating circuit 11 and / or the inductances of further oscillating circuits and a respective high voltage electrode arrangement connected thereto, wherein the capacitance of the second resonant circuit 11 or further oscillating circuits is mainly due to the geometric capacitance or configuration the connected high-voltage electrode arrangement and the layered or mixed dielectric located in the discharge space 3 between the high-voltage electrodes 1, 2, which comprises a gas, such as air, CO ₂ , ₂ , and the process material 4 to be digested or treated. The parallel operation of a plurality of first oscillating circuits 10, which are each magnetically coupled with one or more further oscillating circuits, is within the scope of the invention. The parallel operated first oscillating circuits 10 may have the same or different natural frequencies and a phase shift.

In order to facilitate the dimensioning of the constituents of the device according to the invention to the person skilled in the art, two concrete embodiments will be named below.

Example 1:

The aim is the digestion of grass (process material), for faster utilization in compact biogas plants. The first high-voltage electrode 1 consists of a base plate with the dimen ^¬ solutions 450 mm x 200 mm. On top are 20 Spitzenelekt ^¬ eroden with a tip diameter of 5 mm. The second high-voltage electrode 2 is designed as a grounded, conductive, surface-shaped electrode with dimensions of 450 mm x 400 mm and mounted directly below the conveyor belt 5. The discharge ^¬ space 3 is defined by a distance of 250 mm between the first and second high voltage electrode. First resonant ^¬ circle 10 has the capacity of 17 to 54 nF and the Induktivi ^¬ ty 12 7.5 μΗ. As a switching element 18, an air spark gap is used. The second oscillation circuit 11, which is connected to the first high voltage electrode 1, has the inductance / coil 13 with a value of 30 mH. Due to the constructed high-voltage electrode geometry and introduced into the discharge space grass (process material) results in the capacity of the second resonant circuit 11 to 12 pF. In this embodiment, a high voltage having a frequency (1 / T ₀ ) of 250 kHz is generated. The repetition rate (T _w ) is between 5 ms and 10 ms.

As conveyor 5, a conventional conveyor belt with a conveying speed of about 0.6 m / s is used. On the conveyor belt, the grass is applied as bulk material and moved through the discharge space. The grass lies on the conveyor belt with a bulk ^density of approx. 50 mm.

Example 2:

The goal in this example is the pre-treatment of herbs for faster drying. The first high-voltage electrode 1 consists of a base plate of 450 mm x 200 mm, distributed thereon are 40 tip electrodes with a tip diameter of 2.5 mm. The second high-voltage electrode 2 is formed by a geer ^¬ dete, conductive conveyor with a width of 450 mm. The discharge space 3 is defined with a distance of 150 mm between the first and second high-voltage electrodes. The first oscillating circuit 10 has the capacitance 17 with a value of 44 nF, and the inductance 12 with a value of l4 μΗ. As a switching element, an air - radio link is ^¬ sets. The second oscillation circuit 11, which is connected to the first high tension ^¬ bias electrode 1, the Induktivi ^¬ ty / spool 13 with a value of 30 mH. Due to the constructed high-voltage electrode geometry and the herbs introduced into the discharge space, the capacitance of the second resonant circuit 11 is 20 pF.

In this embodiment, a high voltage having a frequency (1 / T _o ) of 200 kHz is generated. The repetition rate (T _w ) is between 1 ms and 5 ms. As a conveyor 5, a conveyor belt of metal fabric is used with a width of 450 mm, which is connected via sliding ^¬ contacts with ground potential. The conveying speed is approx. 1.7 m / s. On the conveyor belt are the

Herbs in a thin layer, so in the least possible layers, applied and moved through the discharge space 3.

Reference sign list:

1 electrode / high voltage electrode

2 electrode / high voltage electrode / ground electrode

3 discharge room

4 process material

5 conveyor or conveyor belt

6 inclined plane

7 conductive base plate

8 tip electrode

9 ball electrode

10 first resonant circuit

11 second resonant circuit

12 inductance / coil

13 inductance / coil

14 primary coil

15 secondary coil

16 high voltage transformer

17 capacity

18 switching element

T ₀ - reciprocal of the natural frequency f ₀

T _w - repetition rate

Claims

claims

Method for preparing or processing a process material (4) enclosed by a gaseous medium, comprising the following steps:

- introducing the process material (4) into a discharge space (3) between a first electrode (1) and a second electrode (2);

- generating low-energy, spatially extended, repetitive, channel-shaped electrical gas discharges or physical plasmas in the discharge space (3);

- Moving the process material (4) relative to at least one of the electrodes (1, 2) in the discharge space (3) at a predetermined speed.

2. The method according to claim 1, characterized in that the generating of the gas discharges or physical plasmas by applying a high-frequency, repetitive high voltage to at least one of the electrodes (1, 2).

3. The method according to claim 2, characterized in that the high-frequency, repetitive high voltage by a magneti ^¬ cal coupling of at least one first electrical resonant circuit (10) with a second electrical resonant circuit (11) is generated.

4. The method according to claim 2 or 3, characterized in that the high voltage has a frequency (1 / T ₀ ) of 10k Hz to 500 kHz and a repetition rate (1 / T _W ) of> = 1 ms.

5. The method according to any one of claims 1 to 4, characterized in that a residence time of the process material (4) in the discharge space (3) by controlling the relative movement between process material (4) and electrode (1 or 2) is adjustable.

6. The method according to any one of claims 1 to 5, characterized in that the movement of the process material (4) by falling or slipping takes place.

7. The method according to any one of claims 1 to 5, characterized in that a movement of one of the electrodes (1, 2) by moving the electrode via the stationarily positioned process material (4).

8. Device for preparing or processing a process material (4) enclosed by a gaseous medium, in particular biological process material (4), comprising:

- A first and a second electrode (1, 2), between which a discharge space (3) is formed;

- A first electrical resonant circuit (10) and a

second electrical resonant circuit (11) which are magnetically coupled to each other and operate in resonance or near resonance to a repeating high voltage to at least one of the electrodes (1, 2) to generate at low energy in the discharge space, spatially extended, channel-shaped electric To generate gas discharges or physical plasmas;

- A conveying means (5, 6) for moving the process material (4) relative to at least one of the electrodes (1, 2) in the discharge space (3).

9. The device according to claim 8, characterized in that the first resonant circuit (10) comprises a first inductance (12), a first capacitance (17) and a passive switching element (18) for opening and closing the first resonant circuit (10).

10. The device according to claim 8 or 9, characterized in that the second electrical resonant circuit comprises a second inductance ^¬ tivity (13) and a second capacitance, wherein the second capacitance through the electrodes (1, 2) and in the discharge space (3) located dielectric, comprising a gaseous medium and the process material (4) is formed.

11. Device according to one of claims 8 to 10, characterized

characterized in that the conveying means (5, 6) for moving the process material (4) consists of an electrically conductive material so that it itself forms one of the electrodes (1, 2).

12. Device according to one of claims 8 to 11, characterized

characterized in that the conveying means for moving the

Process material (4) is a conveyor belt (5) or a rotating ^¬ disc.

13. Device according to one of claims 8 to 11, characterized

characterized in that the conveying means for moving the

Good for the process (4) is a device (6) exploiting the gravity of the process material.

14. The device according to one of claims 8 to 13 characterized in that the high-voltage electrodes (1, 2) as the opposite large-surface electrodes and / or as a ball or tip electrodes (8, 9) arranged on a conductibility ELIGIBLE base plate (7) are, are executed.

15. Device according to one of claims 9 to 14 characterized

characterized in that the passive switching element (18) is a spark gap.