DEVICE AND METHOD FOR SEPARATING OFF CONTAMINANTS

Abstract

The present invention relates to: a device (1, 101, 151) for separating off liquid and/or particulate contaminants from a gas flow (7, 107), in which a flow path of the gas flow (7, 107) runs between at least one first electrode (9, 31, 109) acting as a counter electrode and at least one second electrode (11, 111, 51, 53, 57, 135, 135, 135, 155) acting as an emitter electrode and having an electrode end (71, 77, 90) oriented in the direction of the first electrode, and a direct-current voltage exceeding the breakdown voltage can be applied between the first electrode (9, 31, 109) and the second electrode (11, 111, 51, 53, 57, 135, 135, 135, 155) in order to form a stable low-energy plasma (41, 125), wherein the second electrode (11) extends substantially along a first axis (X) in a first direction and the first electrode (31) has at least one plateau region (33) which is arranged opposite the second electrode (11) and which extends at least regionally in a first plane running substantially perpendicular to the first direction (X); and a method for operating such a device.

Claims

1.-23. (canceled)

24. A device (1, 101, 151) for separating off liquid and/or particulate contaminants from a gas flow (7, 107), in which a flow path of the gas flow (7, 107) runs between at least one first electrode (9, 31, 109) acting as a counter electrode and at least one second electrode (11, 111, 51, 53, 57, 135, 135, 135, 155) acting as an emitter electrode and having an electrode end (71, 77, 90) oriented in the direction of the first electrode, and a direct-current voltage exceeding the breakdown voltage can be applied between the first electrode (9, 31, 109) and the second electrode (11, 111, 51, 53, 57, 135, 135, 135, 155) in order to form a stable low-energy plasma (41, 125), wherein the second electrode (11) extends substantially along a first axis (X) in a first direction and the first electrode (31) has at least one plateau region (33) which is arranged opposite the second electrode (11) and which extends at least regionally in a first plane running substantially perpendicular to the first direction (X), wherein the plateau region (33) is connected to the base level (37) by means of a spacer element (35) (in particular, an electrically conductive one) extending against the first direction (X), characterized in that the plateau region (33) is connected to the spacer element (35) by means of at least one connecting element (39) that preferably runs substantially perpendicular to the first direction and/or along the first plane.

25. The device according to claim 24, characterized in that the plateau region (33) is arranged coaxially to the second electrode (11), and/or the flow path runs substantially between the second electrode (11) and the plateau region (33), the plateau region (33) has, at least regionally, in particular, in the edge region, a surface that is curved in the direction of the second electrode (11) and/or against the first direction (X), the plateau region (33) is arranged a distance from a base level (37) of the first electrode (31) in the direction of the second electrode (11), and/or a plurality of second electrodes (11) are present, and the first electrode has a plurality of plateau regions (33), wherein each of the second electrodes (11) is associated with a respective plateau region (33).

26. The device according to claim 24, characterized in that the spacer element (35) runs coaxially to the first axis (X), or the spacer element (35) runs at a distance from the first axis (X), preferably at least regionally parallel to the first axis (X), and/or characterized in that the first electrode (31) has, at least regionally, a substantially C-shaped cross-section, in particular, the C-shape being formed of the base level (37), the spacer element (35), the connecting element (39), and the plateau region (33).

27. The device according to claim 25, characterized in that the plateau region (33), the spacer element (35), the base level (37), and/or the connecting element (39) are configured at least regionally as a single piece; the plateau regions (33, 33) are connected by means of at least one connecting device (43, 43) that extends substantially parallel to the base level and/or has a lesser extension in at least one direction of the first plane than the plateau regions (33, 33), wherein the plateau regions (33) are arranged along a straight line in a direction perpendicular to the first axis, in particular, the connecting devices (43) extend substantially along the straight line and/or a network and/or matrix is configured by means of the connecting devices (43), wherein at least one plateau region (33) is arranged on at least one of the points of intersection of the connecting devices (43), wherein the network and/or matrix extends along the first plane.

28. The device according to claim 25, characterized in that the plurality of plateau regions (33) are provided by at least one counter electrode element (31) that is preferably configured at least regionally as a punched sheet metal part, in particular, the plateau regions (33) are arranged in the counter electrode element (31) along a second direction and/or at least two counter electrode elements (31) can be arranged with mirror symmetry relative to one another, preferably at least regionally interlocking with one another, preferably offset from one another in such a manner that the plateau regions (33) of the respective counter electrode elements (31) are arranged offset relative to one another along the respective second direction, or the punched sheet metal part forms the plateau regions (33, 33) and connecting elements (43, 43).

29. The device according to claim 24, characterized by at least one drip element (59, 73, 79, 80, 89) which is operatively connected to the second electrode (51, 53, 55, 57, 83) and by means of which fluid particles of the gas flow that are moving in the direction of and/or along the second electrode (51, 53, 55, 57, 83) can be collected in such a manner that the fluid particles come loose from the drip element (59, 73, 79, 80, 89) at a distance from the electrode end (71, 77, 91).

30. The device according to claim 29, characterized in that the drip element (89) is at least regionally encompassed by at least one approach flow element (85) arranged in the region of the second electrode (83).

31. The device according to claim 29, characterized in that the second electrode (51, 53, 55, 57) encompasses the drip element (59, 73, 79, 80) at least regionally, wherein fluid particles flowing along the second electrode (51, 53, 55, 57) in the direction of the electrode end (71, 77) can be collected at a distance from the electrode end (71, 77) by means of the drip element (59, 73, 79, 80) in such a manner that the fluid particles come loose from the second electrode (51, 53, 55, 57) at a distance from the electrode end 71, 77), wherein, in particular, the electrode end (71) and an infeed end (63) of the second electrode (51) that is opposite the electrode end (71) are arranged offset from one another along a first axis (Y) extending in a first direction in such a manner that the electrode end (71) is arranged close to the first electrode, and the drip element (59) is formed at least regionally by a transition region of the second electrode that is arranged between a first electrode region (61)in which at least one surface region of the second electrode (51) and/or the electrode (51) extends from the infeed end (63) in the direction of the electrode end (71) in a direction with a direction component along the first axis (Y)and a second electrode region (65) in which at least one surface region of the second electrode (51) and/or the second electrode (51) extends at least regionally in a direction with a direction component against the first direction, wherein, preferably, at least one surface region of the second electrode (51) and/or the second electrode (51) extend from the infeed end (63) in the direction of the electrode end (71), in particular, subsequently to the second electrode region (65), in a third electrode region (69) in a direction with a direction component along the first axis (Y), preferably in such a manner that the drip element (59) is arranged along the first axis above the electrode end (71).

32. The device according to claim 29, characterized in that the drip element is encompassed by and/or constituted of at least one winding (75) of the second electrode (53), at least one kink (59, 89) of the second electrode (51) and/or the approach flow element (85), at least one helical region of the second electrode, at least one protuberance (79) of the surface of the second electrode (55) and/or the approach flow element, at least one skirt, and/or at least one disc element (81); the drip element (79, 80) circumferentially surrounds the second electrode; preferably with radial symmetry, the drip element (73) is arranged downstream of the gas flow; and/or the approach flow element (85) is arranged upstream of the gas flow; and/or the drip element (59, 73, 79, 80, 89) is configured at least regionally integrally with the second electrode (51, 53, 55, 57) and/or the approach flow element (85).

33. The device according to claim 24, characterized in that the second electrode (91) has at least one taper (95), in particular, in the region of the electrode end (93).

34. The device according to claim 33, characterized in that the taper is configured in the form of at least one tip, at least one ridge, and/or at least one edge (95).

35. The device according to claim 33, characterized in that the second electrode has a substantially cylindrical, triangular, quadratic, rectangular, and/or polygonal cross-sectional shape in a plane perpendicular to a main extension direction, in particular, the first direction; the second electrode has an end surface inclined with respect to the main extension direction, in particular, in the region of the electrode end; in particular, the taper is encompassed by an edge of the end surface; the second electrode hasin particular, in the region of the electrode end (93)at least regionally a hollow region in which the second electrode is configured so as to be hollow, preferably in the shape of a hollow cylinder, tube, and/or a cone shell; wherein preferably the taper (95) is encompassed by at least one end edge of the wall of the hollow region; in particular, the taper is circumferential on the electrode end (93); and/or the second electrode comprises a carbon material, at least regionally, in particular, in the region of the electrode end; and/or the second electrode comprises at least one coatingpreferably one that reduces the attachment of particles and/or fluid, in particular, a coating comprising titanium nitride, nanosol, at least one nanoparticle-containing material, at least one material constituting a surface having a nanostructure, and/or chromium nitrideat least regionally, in particular, in the region of the electrode end.

36. The device according to claim 24, characterized in that at least one partition element (123) that is substantially impermeable to the gas flow (107) and/or the contaminants and is electrically and/or electrostatically permittive is arranged at least regionally between the flow path and the first electrode and/or the flow path and the second electrode (111).

37. The device according to claim 36, characterized in that the partition element (123) comprises at least one partition film and/or partition membrane and/or comprise polytetrafluoroethylene at least regionally; the partition element (123) touches the second electrode (111), in particular, the electrode end, or the first electrode; and/or at least one discharge opening is provided in the partition element (123) when the partition element (123) is arranged between the first electrode and the flow path, wherein contaminants that have been separated off from the gas flow-in particular, those that collect on the side of the partition element that faces the gas flow-can be discharged by means of the discharge opening into at least one collecting space.

38. The device according to claim 24, characterized in that the device comprises at least two second electrodes (135, 135, 135), preferably a multitude of second electrodes (135, 135, 135), wherein the second electrodes (135, 135, 135) extend out from at least one first support element (131, 131, 131), and at least one drain device (133, 133, 133) is provided in order to reduce an electrostatic charge of the support element (131, 131, 131) and/or to discharge charge carriers collecting on a surface of the support element (131, 131, 131), at least in the region between the second electrodes (135, 135, 135).

39. The device according to claim 38, characterized in that the second electrodes (135, 135, 135) pass at least regionally through the support element (131, 131, 131) and/or that the support element (131, 131, 131) comprise at least one ceramic element; the drain device comprises at least one drainage element (131, 131) that is at least regionally installed on the support element and/or at least regionally embedded in the support element, wherein the drainage element preferably comprises at least one drain coating (131) (in particular, an electrically conductive one), at least one drain fabric (in particular, a polyamide-containing and/or grounded one), and/or at least one metal band such as a copper band, and/or the drain device is configured as a conductive tunnel element, and/or the drain device comprises at least one depression (137) at least regionally configured in the support element.

40. The device according to claim 38, characterized in that the drain device comprises at least one drainage device (133) arranged in the region between the electrode ends of the second electrodes and the support element, wherein, in particular, the drainage device comprises at least one conductive mesh (133), at least one conductive foam, at least one shield element that surrounds the respective second electrode at least regionally and preferably is curved radially outward in the direction of the electrode end, wherein, in particular, the drainage device (133) is at the same electrostatic potential as the second electrodes, and/or characterized in that the drain device (133, 133, 133), the drainage element (133, 133), the drain coating, and/or the drainage device stretch at least regionally along and/or in a first wall (139) and/or second wall (143) that extend(s) at least regionally in a direction between the second electrode (135, 135, 135) and the first electrode (109) in a direction along the first axis (X) and/or in the first direction and/or opens into the at least one inlet opening (141) or an outlet opening (145), and/or along and/or in a third wall (147) that extends at least regionally in parallel to the first support element (131, 109, 131), at least regionally below the first electrode (131), and/or at least regionally on the side of the first electrode (109) that faces away from the second electrode (135, 135, 135).

41. The device according to claim 24, characterized in that the device comprises at least two second electrodes (162), preferably a multitude of second electrodes (162), and at least one influencing device (160) for influencing the electrical field formed by the at least two second electrodes (162) can be and/or is arranged at least regionally between the at least two second electrodes (162).

42. The device according to claim 41, characterized in that the influencing device (160) can be and/or is arranged substantially at least regionally opposite at least one first electrode (163, 163), preferably a plurality of first electrodes (163, 163), and/or a (preferably predetermined) electric potential can be or is applied.

43. The device according to claim 41, characterized in that the influencing device (160) can be and/or is conductively connected to the at least one first electrode (163), the potential of the first electrode (163) can be and/or is applied to the influencing device (160), and/or the influencing device and the drain device, the drainage device, and/or the drainage element are at least regionally configured together.

44. A method for operating the device according to claim 24, wherein a liquid and/or particulate contaminant-containing gas flow is supplied to the device (151), the gas flow is guided at least partially along a flow path configured between at least one first electrode and at least one second electrode (155) in order to separate the contaminants off from the gas flow, and a direct-current voltage exceeding the breakdown voltage is configured between the first electrode and the second electrode (155) in order to form a stable low-energy plasma, characterized in that the method furthermore comprises a cleaning step for cleaning the first electrode and/or the second electrode (155).

45. The method according to claim 44, characterized in that during the cleaning step, a ground potential is applied to at least a first group of a plurality of second electrodes (155), or a voltage that exceeds the direct-current voltage and produces a breakdown between the first electrode and the second electrodes (155) of the first group is applied, in particular, while the direct-voltage for forming the low-energy plasma is applied to at least one second group of the second electrodes, wherein preferably the second electrodes (155) are alternately associated with the first group and the second group.

46. The method according to claim 44, characterized in that in the cleaning step, a mechanical excitation of the first electrode and/or the second electrode (155) is produced, preferably by means of an ultrasonic vibration produced by at least one excitation device (157), wherein preferably at least one piezoelectric element (157) and/or at least one component of an internal combustion engine and/or a vibration transfer device operatively connected to a component of the internal combustion engine in order to transfer vibrations is/are used as the excitation device, and/or the cleaning step comprises the sequential departure of at least two first electrodes and/or two second electrodes by means of a cleaning element such as at least one brush.

Description

[0101] In the drawings,

[0102] FIG. 1 illustrates a schematic cross-sectional view of a separator device according to the prior art;

[0103] FIG. 2 illustrates a detail view of the separator device of FIG. 1 along the section A1;

[0104] FIG. 3a illustrates a schematic cross-sectional view of a counter electrode element according to the present invention;

[0105] FIG. 3b illustrates a top view of the counter electrode element of FIG. 3a from a direction B;

[0106] FIG. 4a illustrates a schematic cross-sectional view of two counter electrode elements according to the present invention;

[0107] FIG. 4b illustrates a top view of the counter electrode elements of FIG. 4a from a direction C;

[0108] FIG. 4c illustrates a schematic top view of a counter electrode according to another embodiment;

[0109] FIG. 4d illustrates a top view of a counter electrode according to another embodiment;

[0110] FIGS. 5a to 5d illustrate schematic representations of different embodiments of an emitter electrode with a respective drip element;

[0111] FIG. 6a illustrates a schematic representation of an emitter electrode with an approach flow element according to the present invention with a drip element;

[0112] FIG. 7 illustrates a schematic cross-sectional view of an emitter electrode according to another embodiment;

[0113] FIG. 8 illustrates a schematic cross-sectional view of a separator device according to the present invention, in which a partition film according to the present invention is used;

[0114] FIG. 9 illustrates a schematic cross-sectional view of a support element with a drain device;

[0115] FIG. 10 illustrates a schematic cross-sectional view of an alternative support element with a drain device;

[0116] FIG. 11 illustrates a schematic cross-sectional view of a separator device according to the present invention with the use of a drainage element in the form of a conductive mesh;

[0117] FIG. 12 illustrates a schematic cross-sectional view of another embodiment of a device according to the present invention for performing a method according to the present invention;

[0118] FIG. 13 illustrates a schematic cross-sectional view of an influencing device in the form of a metal solid body;

[0119] FIG. 14 illustrates a schematic top view of the alternately-arranged paired rows of the emitter electrode and the influencing devices;

[0120] FIG. 15a illustrates a simulated figure of the electric field in the vicinity of the emitter electrode without a grounded end face of the influencing devices;

[0121] FIG. 15b illustrates a simulated figure of the electric field in the vicinity of the emitter electrode with a grounded end face of the influencing devices; and

[0122] FIGS. 16a to 16c illustrate schematic representations of the cross-sectional profile in difference embodiments of the influencing devices.

[0123] FIG. 3a depicts a schematic cross-sectional view of a counter electrode element 31 in a schematic cross-sectional view. FIG. 3b depicts a top view of the counter electrode element 31 from the direction B in FIG. 3a.

[0124] As can be seen in FIGS. 3a and 3b, the counter electrode element 31 has a plurality of plateau regions 33. The plateau regions 33 are arranged coaxially to an emitter electrode 11, which extends along an axis X. The plateau regions 33 are connected to a base level 37 by means of spacer elements 35. As described previously and explained below, other configurations may also be implemented in order to achieve the spacing apart. An electrical connection between the plateau region 33 and the spacer element 35 is produced via a connecting element 39.

[0125] As can be seen, in particular, in FIG. 3a, the spacer element 35 does not run coaxially to the axis X, but rather parallel thereto. Embodiments that are not shown provide that the spacer element runs coaxially to the axis X, so that the counter electrode element is configured so as to be mushroom-shaped. As can also be seen in FIG. 3a, the plateau region 33 has a curvature.

[0126] Therein, in a preferred embodiment (not shown), the curvature is configured, in particular, in an edge region of the plateau region, whereas the central region of the plateau region is flat. This ensures that a stable and broadest-possible plasma cone is formed, while simultaneously also ensuring that, in particular, liquid contaminants will not accumulate on the plateau region, but rather flow off therefrom. The viscosity of the contaminants causes liquid contaminants present at the edge of the plateau region to entrain contaminants present in the small region.

[0127] This off-flow of contaminants is furthermore supported by the formation of an ion wind in the region of the plasma coneboth adjacent thereto and in the interiorthat causes these contaminants to be blown away from the plateau region, in particular, from the flat region.

[0128] The plateau region 33 also ensures that a predetermined shape of a plasma cone 41 will form. It is also ensured that contaminants diverted in the direction of the counter electrode element 31 via the plasma cone 41 can flow directly off from the plateau region 33, in particular, cannot collect in the plateau region and agglomerate and thus lead to contamination of the counter electrode.

[0129] The C-shaped cross-sectional shape of the counter electrode element 31, which can be seen in FIG. 3a, makes it possible to combine two counter electrode elements with each other, as depicted in FIG. 4a. As can be seen, in particular, in FIG. 4b, the counter electrode elements 31 may be arranged with mirror symmetry and slightly offset from one another. This makes it possible for the plateau regions 33 of the respective counter electrode elements 31 to be arranged offset from one another, so that same can each be positioned coaxially to corresponding emitter electrodes 11. Due to the offset arrangement of the counter electrode elements 31, the respective plasma cones 41 can be formed offset from one another, so as to produce a nearly closed plasma wall for the gas flow.

[0130] In an alternative embodiment (not shown), it may be provided that the two counter electrode elements depicted in FIG. 4a are not configured completely identically, but rather have spacer elements 35 of different heights. This creates the ability to arrange the base levels so as to overlap with one another, and simultaneously ensures that the plateau regions 33 are arranged at the same height. Therewith, the plateau regions are evenly spaced apart from the emitter electrodes, and a uniform plasma wall/plasma cone can be formed.

[0131] FIGS. 4c and 4d depict alternative embodiments of counter electrode elements 31, 31. The drawings each depict schematic top views of the counter electrode elements 31, 31. The counter electrode elements 31, 31, too, have plateau regions 33, 33. The plateau regions 33 of the counter electrode element 31 are, however, arranged in the shape of a chain, whereas the plateau regions 33 of the counter electrode element 31 are arranged in the shape of a matrix. This signifies that not every single plateau region 33, 33 is separated from the base level by a spacer element, but rather only plateau regions 33, 33 respectively arranged in the edge region of the counter electrode elements 31, 31 are spaced apart from the base level by suitable spacer elements. The remaining plateau regions 33, 33 are interconnected, or connected to one another with the plateau regions 33 arranged at the edge via connecting devices 43.

[0132] The connecting devices 43, 43 are configured as conductive elements that, however, have a smaller extent than the plateau regions 33, 33 in at least one spatial direction. This causes the plasma cones to form substantially between the plateau regions 33, 33 and the respective emitter electrodes. The plateau regions 33, 33, due to this connection thereof, span an otherwise empty region between the counter electrode elements 31, 31 and the base level.

[0133] The counter electrode elements 31, 31 may be configured as punched sheet metal parts. This ensures that the plateau regions 33, 33 are arranged substantially in the same plane, and, at the same time, makes it easy in terms of construction to produce the counter electrode elements 31, 31.

[0134] This construction ensures that through the substantially barrier-free space below the counter electrode elements 31, 31, the discharge of contaminants separated off in the plasma separator is facilitated. The contaminants can also be more easily transported away from the counter electrode. Preferably here, the region under the counter electrode elements is electroconductively lined and grounded and thus serves as an additional option for separating off the contaminants that pass by the plateau region.

[0135] FIGS. 5a to 5d depict different embodiments of emitter electrodes, 51, 53, 55, and 57. These emitter electrodes are alike in each having a drip element.

[0136] For example, FIG. 5a shows that the emitter electrode 51 has at least one kink 59. The kink 59 constitutes a drip element. The kink 59 subdivides the emitter electrode 51 into different electrode regions. In a first electrode region 61, the emitter electrode 51 extends from an infeed end 63 along the axis Y. The kink 59 is followed by a second electrode region 65 in which the emitter electrode 51 has a direction component that runs against the Y-axis. A further bending 67 is followed by a third electrode region 69 in which the emitter electrode 51 again extends in the direction of the axis Y.

[0137] This causes the electrode end 71, from which the plasma cone forms, to be arranged below the drip element 59. If, now, there should be particlesin particular, oil particlesdriven by an ion wind that collect on the emitter electrode 51, in particular, the electrode region 61, or flow from the support element into the electrode region 61, then the fluid drops gather in the region of the drip element 59 until they come loose from the emitter electrode 51 due to the force of gravity and move in the direction of the counter electrode, in particular, so as to be accelerated by the plasma. This prevents, in particular, the contaminants from being able to collect in the region of the electrode end 71 and being able to lead to charring there.

[0138] FIG. 5b depicts another embodiment of an emitter electrode 53 with a drip element 73. In the emitter electrode 53, the drip element is formed by the lower region of a winding 75. In this embodiment, the electrode end 77 is located upstream of the gas flow, so that after having dripped from the drip element 73, the fluid drops are prevented from being able to move again in the direction of the electrode end 77 and accumulate there again.

[0139] With the emitter electrode 55 depicted in FIG. 5c, a drip element 79 is formed by an annular bulge in the upper region of the emitter electrode 55. The drip elements 79 are shaped, in particular, by a bulge configured on the surface of the emitter electrode 55. In particular, a bulge may be formed by a bulbous coating that comprises, for example, plastic, ceramic, metal, or rubber. The bulge may also have a plurality of annular bulges around the tip, in addition or as an alternative.

[0140] With the emitter electrode 57 depicted in FIG. 5d, a drip element 81 is formed by a disc element 81 of the emitter electrode 57. Then, the disc element 81 is configured in the form of a shield element.

[0141] The configuration of a drip element is not limited to the shaping of the emitter electrode, however. As can be seen in FIG. 6a, the present invention also proposes that an approach flow element 85 be configured in the region of an emitter electrode 83. The approach flow element 85 causes fluid droplets collecting on the surface of the support element 87 to be unable to reach the emitter electrode 83, but rather to be guided along the approach flow element 85 to a drip element 89.

[0142] The drip element thus prevents contamination of the electrode end 90, which could cause the contaminants to be baked in and thus cause charring of the electrode tip, which could lead to a collapse of the plasma.

[0143] FIG. 7 illustrates a cross-sectional view of another embodiment of an emitter electrode 91. The emitter electrode 91 has a taper 95 at the electrode end 93. This taper 95 is formed by configuring the emitter electrode 91 in the region of the electrode end 93 to be regionally hollow, in particular, in the shape of a hollow cylinder. In other words, the emitter electrode 91 has an annular tip at the electrode end 93.

[0144] This constitutes an annular taper 95 on the electrode end 93. This also effectively prevents contamination of the electrode end 93. If, for example, there occurs a contamination, for example, a drop, that runs down along the emitter electrode 91, then same reaches this region of the taper 95, stripping away the plasma in this region of the emitter electrode 91. The plasma cone then, however, wanders along the taper 95 to another part of the circle, until the fluid droplet comes loose and is discharged so as to be accelerated via the plasma of the counter electrode. Depending on the wandering of the contamination on the electrode end, thus, the plasma cone wanders along the taper, preventing the contamination from overheating and baking in on the electrode end or the plasma from detaching from the electrode 91.

[0145] FIG. 8 depicts another embodiment of a separator device 101 according to the present invention. The elements of the separator device 101 that correspond to those of the separator device 1 bear like reference signs, but increased by 100. In contrast to the separator device 1, the counter electrode elements depicted in FIGS. 3a to 4b is used as a counter electrode 109 in the separator device 101.

[0146] Moreover, the gas flow 107 is separated from the region in which the counter emitter electrodes 111 are located by means of a partition element, in the form of a partition film 123, that is permeable to the plasma or electrons. The partition film 123 entails, in particular, a Teflon film. This has the property of being gas-impermeable for the gas flow 107, but permeable to the electrons supplied by means of the emitter electrodes 111. In other words, the partition film 123 prevents the gas flow 107 from being able to penetrate into the region of the emitter electrodes 111 and from being able to cause unwanted contamination there. At the same time, it is ensured that there can be achieved an efficient separating off of contaminants from the gas flow in the direction of the counter electrodes 109 by means of the low-energy plasma, which is arranged through the plasma cone 125.

[0147] Experiments performed on separator devices known from the prior art have shown that the collection of contaminants in the region of the emitter electrodes is favored by there being an electrostatic charge in the region of a support element from which the emitter electrodes exit. Most often, the support element is made of a ceramic material. The present invention now proposes that drainage elements reduce an electrostatic charge of the surface of the support element.

[0148] FIG. 9 depicts a first embodiment of such a drainage element. The support element 131 is composed of a ceramic material in which, however, a drainage element 133 in the form of a conductive mesh is embedded. The mesh 133 causes charge carriers collecting on the surface of the support element 131 to be discharged, i.e., an electrostatic charge of the surface of the support element 131 is prevented in such a manner that contaminants cannot collect in the region of the emitter electrodes 135. Furthermore, a drainage element is formed by the configuration of a depression 137 between each of the electrodes 135. This shaping supports the discharge of the charge carriers due to the electrical conductivity of the material, and increases the resistance against the contaminants reaching the support element.

[0149] FIG. 10 depicts another embodiment of a drainage element. The support element 131 comprises a drainage element 133 in the form of a coating applied to the support element 131. The coating 133 is placed at the same electrical potential as the emitter electrodes 135, and thus prevents an electrostatic charge.

[0150] A corresponding drainage element 133 may, as depicted in FIG. 11, also be implemented in the form of a mesh which is spaced apart from the support element 131 and through which the emitter electrodes 135 pass. In order to prevent an electrostatic charge of the surface of the support element 131, the same electrical potential is applied to the mesh 133 as to the emitter electrodes 135. Furthermore, the distance between the emitter electrodes 135 and the mesh or the projection of the emitter electrode 135 through the mesh is selected so that the plasma is ignited not between the mesh and emitter electrode 135 but rather between the emitter electrode 135 and the counter electrode.

[0151] As depicted in FIG. 8, the inner region of a separator device 101 is surrounded by a support element 119, a wall 139 in which an inlet opening 141 connecting to the inlet line 103 is configured, a second wall 143 in which an outlet opening 145 connected to the outlet line 105 is arranged, and a third wall 147 that is configured under the counter electrodes 109.

[0152] In other embodiments, it may be provided that the drainage elements 133, 133, 133 extend not only in the region of the support element 131, 131, 131 but also are arranged in the region of the first wall 139, the second wall 143, and/or the third wall 147. In this manner, there forms a Faraday cage that prevents additional electrical fields within the separator device that could lead to influencing of the ion wind and to attraction of contaminants to the walls. Thus, all of the walls are at the same potential, in particular, ground potential, so as to prevent an attractive force between the walls and the corresponding contaminants. Surface charges can be removed immediately, in particular, when the drainage elements are connected to ground. To achieve these drainage elements, for example, the intake and outlet routes of the separator device may comprise a conductive material or at least one conductive coating. The housing may also comprise entirely a conductive material or a conductive coating. Here, however, a conductive coating is preferred. Thus, for example, a poorly thermoconductive material may be provided with a suitably electrically conductive coating. This preventsat least, reducesthe formation of condensation on the inner walls of the separator device when the separator device is cooled off.

[0153] Further experiments performed on the separator devices known from the prior art have shown that detrimental turbulence of the blow-by flow in the inner region of a separator device 101 occurs, wherein, in particular, the turbulence causes the blow-by to reach the region of the emitter electrodes. The swirling of the blow-by flow in the region of the emitter electrodes makes it possible for the particles entrained by the blow-by to follow along the upper wall of the separator device to the emitter electrode, thus collected at the tips of the emitter electrodes in the upper region of the separator device. Contamination of the emitter electrodes may impair the functionality of the separator device.

[0154] The present invention now proposes that influencing devices installed between groups of emitter electrodes in the upper region of the separator device influence the electric field formed by the emitter/second electrodes and first electrodes/counter electrodes in such a manner that the ion winds are conducted through the modified electric field so as no longer act detrimentally. The detrimental turbulence of the blow-by should no longer occur, or at least be reduced. This causes no blow-by to flow along the covering to the emitter electrodes, allowing the tips of the emitter electrodes in the upper region of the separator device to remain clean for longer.

[0155] FIG. 13 depicts a first embodiment of such an influencing device 160 in a separator device in the form of a metallic solid body having a substantially C-shaped profile. Therein, the influencing devices 160 are each integrated in the separator device 101 in alternation with a group 165 of emitter electrodes 162 arranged in two rows, wherein the region 168 of the influencing device 160 that runs along the upper wall of the separator device 101 is integrally connected via a connecting region 161 (in particular, a concave one) to the region 169 of the influencing device 160 that runs along the side walls of the separator device. In the lower region, the influencing device 160 is conductively connected to the region 168 of the influencing device 160 of the opposite counter electrodes 163.

[0156] FIG. 14 illustrates a schematic top view of the upper region of the separator device 101, which comprises groups 165 comprising two rows of two emitter electrodes 162 and influencing devices 160. It should be noted here again how the emitter electrodes 162, designed so as to be grouped into two respective rows in the illustrated embodiment of the separator device 101 in FIG. 14, each extend in alternation with an influencing device 160 according to the present invention transversely in the upper region of the separator device 101. Then, an influencing device 160 in the form of a substantially C-shaped insert is continuously repeatedly placed between each two electrode rows 162, in order to be able to protect as much as possible all of the electrode tips through the positive effect of this solution. A distance d between a group 165 of emitter electrodes 162 and the influencing device 160 is herein selected to be so large that there can be no sparking from the emitter electrodes 162 to the influencing device 160.

[0157] FIG. 15a illustrates a schematic representation of the field line profiles of the electric field 164 that is formed by the emitter electrode 162 and the counter electrode (not shown) that is situated in the lower region of the image, if no influencing devices according to the present invention with grounded end face are provided in the interior of the separator device 101. FIG. 15b illustrates a schematic representation of the field line profiles of the electric field 164 for the same emitter electrode 162. The electric field 164 forms between the emitter electrode 162 and the counter electrode (again, not shown) in the lower region. However, now an influencing device having grounded end faces is represented. Within the framework of different tests, it has been shown empirically that the field distribution of the electrode field 164 from FIG. 15b eliminates or at least reduces the occurrence of turbulence in the blow-by, because the ion winds are directed by the modified field shape of the electric field 164 so as to no longer adversely affect the blow-by. In particular, the end faces of the influencing devices 160 bring about a field shift. Thus, the particles are charged and separated off earlier, so that the degree of separation overall rises. This advantageously prevents any blow-by from flowing along the covering to the emitter electrodes 162, and thus allows the tips of the emitter electrodes 162 in the upper region of the separator device 101 to stay clean longer, because fewer particles are deposited on the emitter electrodes 162 than is the case with the field line profiles of the field 164 without influencing devices.

[0158] As described above, an influencing device 160 is provided respectively in alternation with a group comprising two rows of emitter electrodes 162 in the separator device 101, whereby all of the emitter electrode tips are provided to the greatest extent possible from deposits of blow-by particles due to the influencing device. Then, due to the repeating of the influencing device, the positive effect spreads to all of the emitter electrodes or groups of emitter electrodes. It shall be readily understood, however, that it is also possible to install only one single emitter electrode row in alternation with one influencing device, instead of the two emitter electrode rows mentioned here by way of example, or even to install three emitter electrode rows respectively in alternation with one influencing device, or to install a multitude of emitter electrode rows respectively in alternation with one influencing device. A person skilled in the art may, as a matter of course, also provide other arrangements of the emitter electrodes 162 within a group of emitter electrodes 165, instead of electrode rows.

[0159] With the device according to the present invention, the influencing devices 160 entail only the end flanks, such that a solid body such as is used in FIGS. 13 and 14 for the influencing devices constitutes an embodiment of the influencing devices 160 that is not necessarily compulsory. The devices 160 according to the present invention may, for example, also be implemented by using grounded metal sheets or the like. It is also not necessary to configure round connecting regions 161, such as are configured in FIGS. 13 and 14 with the influencing devices 160, in order to achieve the positive effect of the modified field distribution. The rounded connecting regions 161 present in FIGS. 13 and 14 serve, rather, to facilitate installation and facilitate manufacture. Moreover, other cross-sectional profiles of the influencing device according to the present inventionin particular, cross-sectional profiles in a plane perpendicular to the direction of flow of the blow-bymay be implemented without counteracting the positive effect.

[0160] For this purpose, FIG. 16a illustrates another possible cross-sectional shape of the influencing device 160 according to the present invention, which has a curved shape. FIG. 16b illustrates the substantially C-shaped form disclosed in FIG. 13 and FIG. 14, with the individually segment-connecting connecting regions 161. FIG. 16c depicts a third possible cross-sectional shape of the influencing device according to the present invention, wherein lateral continuations thereof branch off perpendicularly from the part that runs transversely in the upper region in the separator device 101, and thus have rectangular connecting regions 167 instead of curves.

[0161] FIG. 12 finally depicts a modification of a device according to the present invention that makes it possible to carry out a method according to the present invention. With the separator device 151, a support element 153 is present, wherein the emitter electrodes 155 are fastened by means of actuators 157 to the support element 153. The actuators 157 have piezoelectric elements that make it possible for the emitter electrodes 155 to be made to vibrate (ultrasonically). This makes it possible to clean the emitter electrodes by removing, by means of ultrasound, contaminants that have stuck to the emitter electrodes 155.

[0162] One embodiment (not shown) may provide that the emitter electrodes 155 may be formed of or at least comprise a shape memory alloy (SMA) material. The shape memory material causes deformation of the emitter electrode to occur when the temperature increases. This deformation causes the deformation of any contaminants or buildup that may be present on the emitter electrode in such a manner as to cause same to flake off from the surface.

[0163] The features disclosed in the preceding description, in the claims, and in the drawings may, both individually and in any combination, be essential for the invention in the various embodiments thereof.

LIST OF REFERENCE SIGNS

[0164] A1 Cut-out

[0165] N Normal direction

[0166] B, C Direction

[0167] X, Y Axis

[0168] D Distance

[0169] 1 Separator device

[0170] 3 Inlet line

[0171] 5 Outlet line

[0172] 7 Gas flow

[0173] 9 Counter electrode

[0174] 11 Emitter electrode

[0175] 13 Connection

[0176] 15 Collecting space

[0177] 17 Partition elements

[0178] 19 Support element

[0179] 21 Thermoset body

[0180] 31, 31, 31 Counter electrode element

[0181] 33, 33, 33 Plateau region

[0182] 35 Spacer element

[0183] 37 Base level

[0184] 39 Connecting element

[0185] 41 Plasma cone

[0186] 43, 43 Connecting device

[0187] 51 Emitter electrode

[0188] 53 Emitter electrode

[0189] 55 Emitter electrode

[0190] 57 Emitter electrode

[0191] 59 Kink

[0192] 61 Electrode region

[0193] 63 Infeed end

[0194] 65 Electrode region

[0195] 67 Bending

[0196] 69 Electrode region

[0197] 71 Electrode end

[0198] 73 Drip element

[0199] 75 Winding

[0200] 77 Electrode end

[0201] 79 Drip element

[0202] 80 Drip element

[0203] 81 Disc element

[0204] 83 Emitter electrode

[0205] 85 Approach flow element

[0206] 87 Support element

[0207] 89 Drip element

[0208] 90 Electrode end

[0209] 91 Emitter electrode

[0210] 93 Electrode end

[0211] 95 Taper

[0212] 101 Separator device

[0213] 103 Inlet line

[0214] 105 Outlet line

[0215] 107 Gas flow

[0216] 109 Counter electrode

[0217] 111 Emitter electrode

[0218] 113 Connection

[0219] 115 Collecting space

[0220] 119 Support element

[0221] 121 Thermoset body

[0222] 123 Partition film

[0223] 125 Plasma cone

[0224] 131, 131, 131 Support element

[0225] 133, 133, 133 Drainage element

[0226] 135, 135, 135 Emitter electrode

[0227] 137 Depression

[0228] 139 Wall

[0229] 141 Inlet opening

[0230] 143 Wall

[0231] 145 Outlet opening

[0232] 147 Wall

[0233] 151 Separator device

[0234] 153 Support element

[0235] 155 Emitter electrode

[0236] 157 Actuator

[0237] 160 Influencing device

[0238] 161 Connecting region

[0239] 162 Emitter electrode

[0240] 163, 163 Counter electrode

[0241] 164, 164 Electric field

[0242] 165 Group

[0243] 167 Connecting region

[0244] 168 Region

[0245] 169 Region