JPH07504256A - Method for removing conductive particles from a gas stream and apparatus for carrying out the method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Method for removing conductive particles from a gas stream and apparatus for carrying out the method The present invention provides a method for producing electrically conductive particles from a gas stream having the features of the inclusion part as claimed in claim 1. A method for removing a child, as well as having the features of the inclusive part as claimed in claim 11. and an apparatus for carrying out the method.

For example, industrial sources or exhaust gases from vehicles, especially diesel engines. It is publicly known that particles can be removed from gaseous streams such as gases using respective filtration devices. It is a method of knowledge. Such a filter is positioned within the gas stream and is filled with the gas stream. . However, filtered particles cannot be removed mechanically or completely removed from the filter. To eliminate this problem, the filter must be removed from the system as soon as it becomes clogged. No. Therefore, in cars with a diesel engine, according to the instructions for use Replace the filter at regular intervals, for example every 5,000 to 15,000 kilometers. raw or need to be removed.

The same can be said for filters used in industrial exhaust gas streams.

The regeneration and removal of such filters represents a great deal of effort, especially in the industrial field.

It is an object of the invention to obtain a filter from a gas stream, which makes it possible to regenerate the filter with very little effort. By providing a method for removing conductive particles and an apparatus for carrying out the method, be.

This object provides a method having the features of claim 1 and a device having the features of claim 11. Therefore, it is achieved.

The method of the present invention for removing conductive particles from a gas stream comprises passing the gas stream through a filter. is based on the concept that particles are thereby separated from the gas flow. conductive particles In order to regenerate a filter clogged with No need to remove the filter. Rather, a filter clogged with particles is In this case, the separated particles are regenerated in a time interval consisting of - and/or use a short arc discharge to burn the particles and by combustion They are processed for a sufficient time to convert them to gaseous products.

The method of the invention offers a number of advantages. Unlike existing methods, the filter is removed from the system. There is no need to completely remove it, reproduce it externally, or get rid of it; This makes the method of the invention extremely advantageous for economic reasons. Furthermore, according to the present invention Regeneration (cleaning) of the filter can be carried out at particularly short intervals and is therefore always available at the shortest possible time. The filter can be regenerated within a period of time. For this reason, severely clogged filters No significant pressure increase in the gas stream is observed due to the increased resistance caused by the filter. more books The method of the invention involves the use of chemicals in the gas stream to remove particles from the filter during regeneration. This method of the invention is also very attractive for environmental reasons, since it does not require any Ru. This simple regeneration of the filter allows the method of the invention to reduce the You can use a filter. For this reason, the method of the invention should be filtered. It exhibits particularly strong separation forces with respect to particles and, as a result, particularly significant cleaning with respect to gas flows. It will show purifying power.

A particularly advantageous embodiment of the method according to the invention provides that electric sparks and/or short-term arcs Refers to the use of direct or alternating current, especially alternating current or high-frequency current, to produce an electric discharge. . In the context of the present invention, electrical sparks and/or short-duration arc discharges are defined as , duration of 0.0001 seconds to 1 second, preferably 0.001 seconds to 0.01 seconds. means a discharge that produces an electric spark or arc over time.

According to another particularly advantageous embodiment of the method of the invention, a single power supply is used to Sparks and/or short-term arc discharges are generated. This embodiment Conductive particles, such as soot particles, are removed from motor vehicles, especially those powered by diesel engines. Preferred when desired to be removed from a gas stream.

Guaranteed that particularly high-energy electrical spark discharges or short-duration arc discharges occur In order to Alternatively, use a power source with a voltage of 2kV to 25kV.

Electrical sparks of particles separated on the filter - and/or short-term arcing The time interval required for combustion depends on the power source used and the type of particles being filtered. It will be done. Typically, the treatment interval in the method of the invention is less than 2 seconds, preferably 0.01 seconds to 1. It is 5 seconds. Particularly in the case of soot and sulfur particles, such burn the particles and convert them into gaseous carbon dioxide or gaseous sulfur dioxide. The above treatment intervals are sufficient for the change.

The average pore size of the filter used in the method of the invention generally depends on the particle size to be filtered. It will be done. Usually this average pore size is between 5 nm and 400 nm, especially between 150 nm and 3 nm. 00 nm, and in special cases filters with larger average pore size as well as smaller Average pore size filters can also be used. From diesel engine exhaust gas When using the method of the present invention to remove soot particles, the pore size is typically adjusted to Use filters that vary within a range of physical values.

According to a particularly suitable embodiment, the gas stream is divided into two separate gas streams, each gas Install a separate filter in the stream. This embodiment of the invention typically involves a gas flow or a relatively Used in cases involving high concentrations of conductive particles, with different intervals between regenerations. , it becomes possible to make it longer. In addition, if only one filter is filled , it is also possible to use this implementation in such a way that the other is playing It is.

In order to speed up the conversion of electrically conductive particles into gaseous products, the present invention is particularly advantageous. Embodiments of the method include adding air and/or acid to the gas stream during filter regeneration. It is a basic addition.

As has been repeatedly stated above, the method of the present invention and the apparatus described below are particularly useful for used to separate soot particles from diesel engine exhaust gases. This is a book The method of the invention allows for a particularly quick and simple regeneration of the filter, so that it is relatively compact and compact. This makes it possible to use a lightweight filter that does not take up much space, for example in the exhaust of a car. This is due to the fact that it can be built into the pipe.

Furthermore, the present invention also relates to an apparatus for carrying out the method of the present invention. Ru.

The inventive apparatus for carrying out the inventive method described above may be filled or overfilled with a gas flow. Consists of a filled filter. To induce electrical sparks and/or arcing at least two electrodes and at least one counter electrode are placed on the filter. and these at least two electrodes and at least one counter electrode are connected to one power source.

In this device of the present invention, when both electrodes and the counter electrode are connected to a power source, the filter becomes conductive. As soon as the particles become covered, electrical sparks and and/or short-term arcing occurs and particles are separated at the filter. It has certain decisive advantages. In operation in this situation where regeneration is required, The distance between the particle layer and the counter electrode decreases as well, so that the counter electrode The shortening of the distance between the conductive particle layer and the conductive particle layer causes a spark or arc discharge to occur as described above. Occur. As a result, the separated particles ignite and burn, thus forming gaseous products. converted. As the regeneration progresses, the distance between the burning particle layer and the counter electrode becomes continuous. increase. When a critical distance is reached (this critical distance is determined by the geometry of both electrodes and the counter electrode) (depending on the geometric arrangement), electrical spark discharges or arc discharges are automatically shut off. Ru. At this moment the filter has been completely regenerated. filter cleaned Only when the part is covered again with conductive particles and needs another regeneration can the next A flash or spark discharge is initiated.

The counter electrode or the distance between the counter electrodes is chosen to prevent complete filling by particles It must be. If this happens, the gap will be filled with particles and the counter electrode A short circuit can form between the particle layers or between the counter electrode and the electrode, resulting in an arc or spark discharge. The occurrence of this will end. This distance is preferably about 2 mm to about 1 It is 0mm.

The device of the invention forms a thick layer of separated conductive particles on the filter. It has the decisive advantage of always producing a spark or arc discharge when Ru. Since the generation of sparks or arc discharges is bound to occur, the device of the invention is equipped with a control element. There is no need to add. The termination of the spark or arc discharge is also an automatic process, and the distance This is done by increasing the distance, and no control element is required for this purpose. That is, the present invention The device is particularly simple and does not require any additives to the gas stream. Allows effective filter regeneration, combustion or separation of particle layers from the filter surface encourage. Furthermore, since the device of the present invention is extremely simple and lightweight, it saves both weight and space. It can be used in extremely important systems, especially the exhaust system of automobile diesel engines.

This is installed in the exhaust gas stream of a diesel engine, especially in the exhaust pipe in the area of the silencer. attaching a filter and at least two of said electrodes and at least one counter electrode; Just that is enough. The independent regeneration described above requires relatively little space.

The design of the filter will depend on the intended use of the device of the invention.

According to a first embodiment of the device of the invention, the filter is a filter tube, preferably a ceramic It is shaped like a filtration tube made of wood. Such a filter tube is installed in a corresponding cylindrical exhaust pipe. Especially suitable for wearing. filtration tube so that particles are separated on the outer surface of the filtration tube It is very practical to mount the device in the gas stream.

Instead of ceramic filter tubes, use other materials, such as non-conductive steel or glass. It goes without saying that you can also use heat-resistant materials. good. Also, fix the filtration tube in the gas stream so that the particles are separated inside the filtration tube. You can also.

The location and design of at least two electrodes connected to the filter depend on the filter used. depends on the type of The above cylindrical filtration tube has at least two electrodes arranged in a ring shape. electrodes and attach them to the filtration tube, especially on the surface of the filtration tube, and It is suitable to provide it in direct contact with the pipe. These annular electrodes will be used in later examples. As will be explained in detail in , they are configured with a distance between their axes.

The design of the counter electrode required for the present invention involves repeating the previously described spark- or arc-emitting the counter electrode so that electricity is generated between the conductive particles separated on the filter and the counter electrode. The design and location are important. Therefore, it has a cylindrical filter tube. In the embodiments described above in which the counter electrode is radiologically and as a single row of counter electrodes distributed directly between the filters. suitable for building. Especially if at least two electrodes have an annular shape It is preferable that the counter electrode or a row of counter electrodes be annular electrodes of the same shape. ring-shaped electric The diameter of the counter electrode in the form of a pole is much larger than the diameter of the electrode connected to the filtration tube; By means of a continuous radial topography between the cylindrical filtration tube and the counter electrode in the form of an annular electrode. distance is guaranteed.

According to another embodiment of the device according to the invention, the filter is not constructed as a tube.

Rather, this embodiment provides the filter as a plate-like system; A filter consists of a number of plates spaced apart from each other that control the direction of gas flow. It is preferable that it be fixed so as to be located in the direction or in the direction that intersects therewith. gas Depending on the concentration of particles in the stream, the system may contain from 2 to 20 plates.

Regarding the position of the plate relative to the direction of the gas flow to be cleaned, and intersect, preferably at an angle of 90°.

Particularly suitable variants of the above-mentioned embodiments of the invention characterized by a particularly long duration According to are fixed at mutually distant positions to form a gas flow path. This kind of effect To obtain this effect, the filter plate must be positioned in the direction of the gas flow and By using a suitable block element or current transformation element in the flow path, the gas can be Allow the stream to pass through the filter plate one or more times.

According to certain variations of the embodiments described above, a partition, in particular a gas-tight partition, can be connected to an adjacent filter. between the plates of the filter, so that the gas flow is divided into several single gas flows as described above. each single gas stream is separated from the adjacent gas stream by a single gas-tight partition. .

In the device of the invention, which includes a filter as a plate filter, sparks and/or Each filter plate should have at least one Both are provided with electrodes at two separate locations. Furthermore, at least two The counter electrode of each of the electrodes is placed at the same distance. This allows the counter electrode and the two electrodes to Allows for reproducible, failure-free sparking and arcing between the filter section and the The filter part is then covered with a layer of conductive particles, so that this part must be played.

In the above modification where adjacent filter plates are connected by a septum, the counter electrode is made airtight. It is best to fix it at the bulkhead.

According to another advantageous embodiment of the device according to the invention, which consists of a number of counter electrodes, each counter electrode or or each electrode has at least one electrode connected between its respective counter electrode or electrode and a power source. connected by one capacitor. Such decoupled electrodes are It allows current limiting without any actual losses and reduces the capacitance of the capacitor. Variation limits the nature of the discharge and keeps it at a predetermined level. Additionally, this modified example In some cases, it is possible to prevent discharges from occurring at only one electrode or at several electrodes. , so that the discharge spreads in all areas of the filter. Furthermore, that Such a device can assist in generating an infinite number of electrical discharges, with each single counter voltage The poles and electrodes are coupled to one single power source.

Use a resistor instead of a capacitor connected to each single counter electrode or electrode You can also do that. However, the use of such resistors results in some energy loss due to heat. May induce loss.

The above of the device of the invention having a capacitor coupled to each counter electrode or each electrode. A particularly suitable variation of the embodiment provides for the use of coaxial cables for the capacitors. Ru. This modification is a long-lasting product that is relatively light in weight and is particularly easy to install in cars. There is a place. Additionally, the capacitance of such a coaxial cable capacitor is It can be varied particularly easily by adjusting the length of the . The device of the present invention In this example of a change in position, the nature of the discharge is employed as required to change the working conditions. can be quickly changed in any way that is desired.

The capacitance of the capacitor connected between each counter electrode and the power supply is between 5 pF and 50 pF. 00 pF, preferably 100 pF to tsoopi:'.

Variations in which several electrodes or counter electrodes are connected to one single power source as described above. In a further example, each electrode and counter electrode are connected in parallel.

The electrode and counter electrode materials are generally conductive, especially those that do not oxidize or corrode under the conditions of use. A conductor is selected. This means that, in individual cases, the electrode or counterelectrode may be aluminum, iron ( steel), copper, platinum, platinum alloys, tungsten or nickel. Taste. For economic reasons, the use of aluminum, steel or iron is preferred.

According to another particularly suitable embodiment of the device according to the invention, each counter electrode is connected to a second capacitor. In this second capacitor, the electrodes are connected to their respective counter electrodes. It is. This second capacitor controls the timing of the spark or arc discharge. This allows the range of discharge frequencies to be varied. make it possible.

The capacitance of this second capacitor depends on the desired modulation, and the capacitance of this second capacitor is smaller than or has the same capacity as the first capacitor. server is preferred.

Specifically, the capacity of the second capacitor is 10% of the capacity of the first capacitor. It is 90%.

The above change in the capacitance of the second capacitor is due to the fact that the coaxial cable is again connected to the second capacitor. This is particularly easily accomplished when used as a capacitor. coaxial cable length The desired capacitance of the second capacitor can be obtained by changing the capacitance of the second capacitor.

Use a power source suitable for creating alternating current as the power source connected to the electrode and counter electrode. Or preferable. Typically such devices operate between 5Hz and 20,000Hz, preferably An alternating voltage with a frequency of 50 Hz is generated.

The desired voltage produced by the power source depends on the design of the counter electrode and its associated electrode. Depends on structure. Typically, the device of the invention operates between 500v and 50kV, preferably It includes a power supply that provides an alternating voltage of 2kV to 25kV.

In summary, the method and method of the present invention in which a gas stream is divided into at least two single gas streams; Modifications of the device of the invention have been described. Attaching a separate filter to each single gas stream Preferably, it is used in conjunction with a gas stream and is filled thereby. to this to filter out large amounts of particles from a gas stream or to regenerate a filter to an unfilled condition. becomes possible.

To speed up filter regeneration and promote the conversion of conductive particles into gaseous products, this book In another advantageous embodiment of the inventive device, a fresh air intake and/or an acid An ordinary opening is provided and its position is in front of the filter with respect to the direction of gas flow. be. Such a fresh air intake and/or opening for oxygen may be Consists of a valve and one sensor, the valve is opened and closed by a control signal for opening the valve. do. The sensor detects when a current flows between the electrode and the counter electrode for the opening of the valve. A control signal is coupled to generate a spark-and/or short-term This is the case when an arc discharge occurs.

In the above and subsequent descriptions, spark- and/or arcing The expression "short time" is used many times. This means that the discharge is 10-' means occurring within a time period of 10-” seconds, preferably lO-@ to 10-! seconds do.

According to a particularly suitable embodiment of the device according to the invention, the filter is installed at the same time in the diesel engine. This embodiment is especially economical in terms of space saving. Ru.

Preferred variants of the device according to the invention are described in the dependent claims.

The device of the invention is further illustrated by two exemplary embodiments in conjunction with the drawings.

These drawings are Figure 1 is a general drawing, Figure 2 is an example of a modification of the drawing in Figure 1. Figure 3 is a sectional view of the first embodiment of the device, and Figure 4 is a cross-sectional view of the second embodiment of the device. A cross-sectional view, and FIG. 5 shows the flow of a gas stream containing particles in the embodiment shown in FIG. A sketch is shown.

In FIGS. 1 to 5, the same parts have the same numbers.

Figure 1 shows a schematic general diagram, which includes the implementation described in Figures 3 to 5. used in embodiments. This configuration includes a power supply l, which has a voltage of 5kV and generates alternating current with a frequency of 50 Hz. This power source l has three typical electrodes. 2.3 and 4 and three typical counter electrodes 5.6 and 7, this Electrodes 2.3 and 4 and counter electrodes 5.6 and 7 are connected in parallel.

Each counter electrode 5 to 7 is connected to a capacitor 8.9 or lO, each capacitor -8 to 10 have a capacitance of 500 pF. In other words, the counter electrode 5 is not 7 is decoupled, which is connected to electrodes 5 and 2, electrodes 6 and 3, and electrode 7. and 4, an electric spark - or This means that arcing and/or arcing occurs, and the limit of 1: is the distance between the electrodes and It depends on the capacitance of capacitors 8 to 10. This spark- and/or During the discharge, an alternating current flows through each capacitor 8 to IO.

The configuration shown in FIG. 2 differs from the first configuration in that it includes a second capacitor 11.

Again, this configuration consists of a power supply 1, a first capacitor 8, and a counter electrode 5 and a voltage Includes a single illustrated electrode pair consisting of poles 2. A second capacitor is connected in parallel to electrodes 5 and 2. server 11 is connected, which causes a spark to occur between tfi5 and tfi2 and/or Induces a modulation of the arc discharge time. Capacitor 11 is the first capacitor It has a capacity in the same range as . Power supply 1 carries the same voltage as described above for Figure 1. Occur.

FIG. 3 shows a first embodiment of the device, which consists of a cylindrical ceramic filter. It includes a tube, which is connected to a cylindrical case 21 surrounding the filter tube. filtration There is a cylindrical annular space 22 between the tube 20 and the case 21, through which the particles pass. For example, the exhaust gas of a diesel engine containing soot particles is It flows in the direction of mark 23. Each cylindrical annular space is once closed by a closing element 24. Due to the fact that it is chained, the gas flow is forced into the internal space of the filter tube 2o. and passes through this filter tube in the direction of arrow 25. This phenomenon causes particles to be removed from the filter tube 20. It is possible to separate it as a layer 26 on the outside.

The filter tube 20 is connected with three typical electrodes 2 to 4, and the case 21 has two typical counter electrodes 5 and 6. Electrodes 2 to 4 and counter electrode 5 and 6 are annular and connected as shown in FIG. conductive layer 26 As soon as the layer 26 is deposited on the outside of the filter tube and has a thickness of this layer, the electrode 2 or 4 becomes electrically conductive, so that the thickness of the layer reaches its limit. Then, as shown at position 27, an electric spark is generated between the layer and the counter electrodes 5 and 6. and/or arcing. As a result of the electrical discharge, the layers 26 ignite and the respective layers The substances in the layer turn into gases, allowing the combustion of the substances in the layer and the regeneration of the filter. layer loss over time During the process, the conductivity of the layer is disturbed and the combustion automatically stops after the complete combustion of the filter tube. Stop.

The latter embodiment allows the thickness of the filtration tube to be adjusted without the need for a particularly complex control system. The advantage is that the filtration tube can be automatically regenerated. The same applies to the second embodiment below. The same thing can be said.

The embodiment shown in FIGS. 4 and 5 uses a plate filter instead of the ceramic filter tube 20. This embodiment differs from the previous embodiment in that it uses a filter 30, and the plates are spaced apart from each other. . Between each plate 30 there is a gas-tight partition 31 which is connected to the gas flow or the closed element in front. The presence of child 33 causes the flow through filter plate 30 in the direction of arrow 32 (FIG. 5). to force. Conductive particles in the gas stream are filtered out as they flow through the filter plate. , causing the deposition of an electrically conductive layer of filtered particles on the surface of the filter plate 30.

Electrodes 2.3 and 4 are arranged on the gas-tight partition 31 and counter electrodes 5 and 6 are placed on the filter plate 3. 0, and its configuration is as shown in FIG.

When the particle layer 34 on the surface of the filter plate 30 is sufficiently thick and uniform, it becomes conductive. When a certain layer thickness is reached, sparks and/or sparks occur between the conductive layer and the electrode. Or arcing occurs. This ignites the particles and converts them into gaseous products. As a result, the filter is automatically regenerated. Combustion process or end accordingly As the distance between the electrodes increases, another layer of constant thickness is formed on the surface of the filter plate. Until then, no discharge occurs. Therefore, in this embodiment, the first embodiment and all ( Similarly, a similar automatic regeneration initiation without the need for any complex control elements and The end will come.

The above-described embodiments of the invention are particularly suitable for removing soot from the exhaust gas of automobile diesel engines. Particularly suitable for removing particles of

FIo, 5 International search report PCTloE 93100705 Front page continuation (72) Inventor: Wienetzke, Rudolf, Federal Republic of Germany, D-85579 Neubiberg, Alb Rechtodeurerubeke (no street address) (72) Inventor: Truckenmuller, Tart, Federal Republic of Germany, Day-74 076 Heilbronn, Karluvlestraße (72) Inventor Trut Kenmüller, Roman Germany, D-74223 Frein, Que. Luckelstrasse 23

Claims (40)

[Claims] 1. Pass the gas stream through the filter, separate the particles from the gas stream, and regenerate the filter containing particles A method for removing conductive particles from a gas stream, the filtered particles igniting; Allow sufficient time for the ignited cane to be converted to gaseous products by combustion, and filter. The evaporated particles are treated with electrical sparks and/or short arc discharges. It is characterized by regenerating filters clogged with particles by a steady method of A method for removing conductive particles from a gas stream. 2. Said spark and/or arc discharge is caused by an alternating or direct voltage, in particular an alternating current voltage. 2. A method according to claim 1, characterized in that the voltage or high-frequency voltage is generated. 3. Multiple sparks and/or arcs may be generated using a single power source. The method according to claim 1 or 2, characterized in that: A power supply with a voltage of less than 4.50 kV, preferably between 500 V and 50 kV is used. A method according to any one of the preceding claims, characterized in that: Claim 4, characterized in that a power supply with a voltage of 5.2 kV to 25 kV is used. Method described. 6. said filtered particles for less than 2 seconds, preferably from 0.01 seconds to 1.5 seconds. before being treated with said spark and/or arc discharge during A method according to any one of the preceding claims. with an average pore size of 7.5 nm to 400 nm, in particular 150 nm to 300 nm. A method according to any one of the preceding claims, characterized in that a filter is selected that 8. dividing said gas stream into at least two separate gas streams, each of said gas streams The method according to any one of the preceding claims, characterized in that one filter is used for Law. 9. The method of claim 1, characterized in that air is added during regeneration of the filter. The method described in any one of the above. 10. Characterized by filtering soot particles from diesel engine exhaust gases A method according to any one of the preceding claims. 11. Apparatus for carrying out a method according to any one of the preceding claims, comprising: a filter (20, 30), said filters (20, 30) being electrically sparked and/or at least two electrodes (2-4) for generating an arc discharge between and At least one counter electrode (5-7) is arranged, and said at least two counter electrodes (5-7) are arranged. The electrodes (2-4) and at least one counter electrode are connected to one power source (1). A device characterized by: 12. Particularly, the filter is installed in the exhaust system of a diesel engine. 12. The apparatus of claim 11, wherein the apparatus comprises: 13. Said filter is in the form of a filter tube (20), preferably a ceramic filter tube. 13. The device according to claim 11 or 12, characterized in that it has a shape. 14. The filter is arranged so that the particles to be separated (26) are filtered outside the filter tube (20). 14. Device according to claim 13, characterized in that the tube (20) is fixed in the gas stream. Place. 15. At least two annular electrodes (2- 4) is arranged in the filter tube (20). 15. The device according to any one of item 14. 16. a distance radially and axially from said at least two electrodes (2-4); At least one counter electrode (5, 6) located at a distance from said filter tube (20) According to any one of claims 13 to 15, the Device. 17. Claim characterized in that said counter electrodes (5, 6) are in the form of annular electrodes. The device according to item 16. 18. A claim characterized in that the filter (30) is in the shape of a plate-like filter. The device according to item 11 or 12. 19. Said filter comprises a number of single filter plates (30), preferably from 2 to 20 19. Device according to claim 18, characterized in that it consists of two filter plates (30). 20. The filters are fixed at such a distance that they create a gas flow path from each other. 20. The device according to claim 18 or 19. 21. Between adjacent filter plates (30) there is a partition (31), preferably an airtight partition. 21. Device according to claim 20, characterized in that there is. 22. At least two electrodes (2, 3) spaced apart from each other are arranged on each filter plate (30 ) according to any one of claims 18 to 21. equipment. 23. Said counter electrode (5, 6) is located at the same distance from each of the two electrodes (2, 3). 23. The device of claim 22, further comprising: 24. The counter electrode (4, 5, 6) is arranged on the partition wall. 22. The device according to claim 21. 25. Each counter electrode (5-7) is connected to at least one capacitor (8-10). The capacitor is connected to the corresponding counter electrode (5-7) and the power source (1). Claims 11 to 24, characterized in that: equipment. 26. The above-mentioned continser (8 to 10) is characterized in that it is in the shape of a coaxial cable. 26. The apparatus of claim 25. 27. The capacitance of the capacitors (8 to 10) is 5 pF to 5000 pF, 26. Preferably 100 pF to 1500 pF. or 26. 28. The electrodes (2 to 4) and their counter electrodes (5 to 7) are made of metal, in particular iron, aluminum. The material according to claims 11 to 27, characterized in that it is made of aluminum or copper. The device according to any one of the above. 29. Particularly, a second capacitor (11) is placed on each counter electrode (5). 29. A device according to any one of claims 25 to 28, characterized in that 30. Said second capacitor (11) connects the counter electrode (5) to the electrode (2) 30. A device according to claim 29, characterized in that: 31. the second capacitor is smaller than the first capacitor; 31. Device according to claim 29 or 30, characterized in that it has the same capacity. 32. A large number of mutually spaced electrodes (2 to 4), in particular 2 to 40 electrodes, filters (20, 30), and the electrodes (2 to 4) are connected in parallel. are connected to the same power source, and the counter electrodes (5 to 7) are electrically decoupled. 32. A ring according to any one of claims 11 to 31. Device. 33. Particularly, the electrodes (2 to 4) are connected to one AC power source (1). 26. A device according to any one of claims 11 to 25, characterized in that: 34. The power source (1) has a frequency of 5Hz to 20000Hz, preferably 50Hz. 34. A device according to claim 33, characterized in that it generates an alternating voltage having a frequency. 35. The power source (1) is 500V to 50kV, preferably 2kV to 2 Any one of claims 11 to 34, characterized in that an alternating current voltage of 5 kV is generated. The device according to item 1. 36. characterized in that a filter (20, 30) is arranged in each single gas stream 36. A device according to any one of claims 11 to 35. 37. A new filter is installed upstream of the filter (20, 30) in the direction of gas flow. Any one of claims 11 to 36, characterized in that it has a fresh air intake. The device according to item 1. 38. said fresh air intake includes a valve and a sensor, said valve including a sensor; 38. The device according to claim 37, wherein the device is opened and closed by a control signal issued by the sensor. 39. Said sensor is arranged on said electrode (2-4) and counter electrode (5-7) and when a current flows between the counter electrode (5 to 7) and the electrode (2 to 4), 39. Apparatus according to claim 38, characterized in that it generates a signal for opening the valve. . 40. The filter (30) is constructed as a silencer for a diesel engine. 40. A device according to any one of claims 11 to 39, characterized in that: