DE102009034707A1 - Device for treating liquid medium, comprises an opening for passing the medium, and a first electrode with a first electrode surface and a second electrode with a second electrode surface spaced and parallel to the first electrode surface - Google Patents

Abstract

The device comprises a first opening for passing a liquid medium, a first electrode (3) with a first electrode surface (5) and a second electrode (4) with a second electrode surface (6) spaced and parallel to the first electrode surface, an electrically non-conducting housing (2), within which the first and second electrodes are present. The first opening is arranged in the electrode surface and the first electrodes has a first conduction path, which connects an electrically separated line with the first opening in the first electrode surface. The second electrode surface is a closed surface. The device comprises a first opening for passing a liquid medium, a first electrode (3) with a first electrode surface (5) and a second electrode (4) with a second electrode surface (6) spaced and parallel to the first electrode surface, an electrically non-conducting housing (2), within which the first and second electrodes are present. The first opening is arranged in the electrode surface and the first electrodes has a first conduction path, which connects an electrically separated line with the first opening in the first electrode surface. The second electrode surface is a closed surface. The first opening is centrally arranged in the first electrode surface. The first electrode surface and/or the second electrode surface have a circular outer circumference. The second electrode surface is circular and consists of an electrically non-conducting material in a surface section opposite to the opening of the electrode surface. The first and second electrodes are liquid-tightly connected through the wall of the housing. The first electrode surface and the second electrode surface are arranged in a distance from the wall of the housing. The housing has an opening for the passage of the medium. The second electrode has a second conduction path and a recess in a distance to the second electrode surface for the passage of the medium. The recess is connected with the second conduction path. The second electrode has an opening for passage of the medium, where the second conduction path is connected with the opening of the second electrode. The device is designed to flow the medium rectified by the first opening in the first electrode surface and a second opening in the second electrode surface in relation to the intermediate space between the first and second electrode surfaces. The second conduction path is connected with the electrically separated second line in connection to the second electrode. An independent claim is included for a method for treating a liquid medium.

Description

The The invention relates to apparatus and method for the treatment of Liquids in the pulsed electric field, in particular for continuous treatment of liquids, or liquid and pumpable media, especially food are. Pumpable media with the inventive Procedures that can be treated may be lumpy Have constituents, since these are also digested with the process or their germ content is also reduced. The pulsed electric field is generated between electrodes between which the liquid is guided, so when flow the liquid through the electric field a continuous Treatment is achieved.

The Invention provides a device with an electrode assembly ready with the high-voltage pulse treatment of liquids can be carried out continuously, and use the device in a method for high voltage pulse treatment. The device according to the invention is particularly suitable for applying strong electric fields in a short duration, for example by Actuation of the electrodes in the device with impulse powers from about 3 to 10 MW, in particular 5 MW, with a pulse duration of 10 to 30 μs, in particular 20 μs, at a time of 3,000 of the 5,000 μs between the pulses, in particular 4,000 μs, or an average power of about 15 to 50 kW, in particular 25 kW.

The High voltage pulse treatment, also called electroporation, is used among other things for sterilization and / or cell disruption in food, Medicines, waste water, substrates and feed, since it leads to perforation of the cell wall in biological cells, and therefore at least partially digesting and / or reducing the Germ load or for sterilization. The special electrode shape the device of the invention allowed because of the uniformity of the generated electrical Feldes a uniform treatment method, and preferably a method with less energy expenditure for the electric field, as known electrode arrangements. For the digestion or the sterilization of food are z. B. field strengths of 15-20 kV / cm suitable.

State of the art

The WO 2005/093037 A1 describes a device for the extraction of grapes, in which electrodes are embedded flush in the surface of a tube to generate when applying high voltage pulses between them an electric field in the flowing medium. The electrodes may protrude radially into the tube in the shape of a pencil or may be annular and may be arranged at a distance coaxially with the tube.

The DE 60933273 T2 shows a device for high-voltage pulse treatment, in which a first tubular electrode is arranged around a spaced coaxial second electrode, so that the electrodes between them form a flow channel with annular cross-section.

The EP 1123662 B1 describes a device for high-voltage pulse treatment, in which the electrodes should be arranged in a treatment chamber so that the field lines of the electric field generated by the electrodes are parallel to each other, and the potential control should be designed so that the strength and direction of the electric field in the effective Flow area are constant. The treatment chamber may be a rectangular housing in which the electrodes are spaced apart from one another. Alternatively, electrodes may be embedded in the inner wall of a tube parallel to the longitudinal axis.

at the coaxial arrangement of electrodes is the high voltage field not homogeneously distributed so that there are areas in the annular Gap formed by the electrodes in which the medium to be treated a significantly reduced maximum field strength experiences.

Therefore is in known devices for high voltage pulse treatment disadvantageous in that insulating material is arranged between the electrodes, that with a voltage flashover between the electrodes can be changed, and these changes then a voltage flashover on the same Facilitate the job.

Lelieveld et al. (Food Preservation by Pulsed Electric Fields, CRC Press, p. 73, (2007)) schematically show the coaxial arrangement of two electrodes and the arrangement of two plate-shaped electrodes perpendicular to the longitudinal axis of a tube.

at Arrangement of electrodes at a distance parallel to the main flow direction, as is usual with coaxial electrodes, is particularly problematic that insulation material be arranged between the electrodes must, for example, as part of the treatment cell. Because the insulation material is exposed to the high voltage field and is z. B. in inhomogeneities of the liquid medium, for example, trapped air bubbles, by flashovers damaged.

Object of the invention

It is an object of the invention to provide an alternative device and a durchzufüh with the device to provide a method of high voltage pulse treatment of alternative construction.

General description of the invention

The Invention solves the problem with the features of the claims and in particular provides a device for continuous treatment liquid media by high-voltage pulse discharge, the at least one first and at least one second with a high voltage pulse generator electrically connected electrode whose electrode surfaces are parallel and spaced apart, and preferably both plan, alternatively curved dome-shaped. According to the invention it is provided that the to be treated liquid medium through a first opening in the Space between the opposing electrode surfaces supplied or can be discharged therefrom, wherein the opening is arranged in one of the electrode surfaces is, preferably centrally, wherein the electrode surfaces around the opening are rotationally symmetric. This opening may be formed by one or more recesses in the first electrode surface be. Preferably, the opposite second electrode surface closed, with their section opposite the opening alternatively to an electrically conductive electrode surface may consist of insulating material. When applying high voltage pulses is in the interspace of the first electrode surface and the spaced second electrode surface is limited is generated, the electric field for the treatment of the medium.

The First and second electrodes may be non-conductive Housing includes. Preferably, the first and second Electrode surface spaced from the housing, z. B. by the electrodes respectively over the inner wall of a Housing protrude. Electrodes are for the Purpose of the invention electrically conductive and exist made of electrically conductive material, for. Metal or Graphite.

The Device according to the invention achieved through an opening for the passage of medium within one of the electrode surfaces a uniform flow of the medium through the electric field that is between the spaced parallel Electrode surfaces can be generated. By placing an opening for the passage of medium in the first electrode surface is not an insulating material between or adjacent to the gap present between the electrode surfaces and the electrode surfaces may be spaced from the housing, for. B. by an electrode portion passing through the wall of the housing protrudes. Therefore, the inventive allows On the one hand, the generation of a uniform High voltage field between the spaced parallel electrode surfaces, on the other hand, because of the absence of dielectric material adjacent to or in the region of the gap between the electrode surfaces an impairment of the insulation of the electrodes against each other avoided. In particular, a first opening for passage of medium exclusively within one of first and second second electrode surface, z. B. arranged in the first electrode surface, while the housing may be closed and / or optionally a second opening for the passage of medium in the housing and / or in the second electrode at a distance is arranged from the second electrode surface.

Preferably is the first opening to the inlet and / or outlet of the medium to be treated centrally in the one electrode surface arranged symmetrically around this opening a uniform To generate high voltage field.

The Housing can be sealed liquid-tight, so that the opening within the one electrode surface is usable as a feed of medium into the housing, or as a drain of medium from the housing, preferably the housing provided with a device for pressure equalization is. In this embodiment, the housing a container for treated or for be treated pumpable medium whose internal volume to the Germ reduction or required for the digestion of the medium limited duration of the continuous treatment process.

For a continuous treatment it is preferred that the device has a housing of non-conductive material and the electrodes are arranged at least with their electrode surfaces respectively within the housing, wherein at least the first electrode has an opening within its electrode surface, optionally the second electrode surface has no opening , and the housing has a second opening. In this embodiment, the opening within the first electrode surface may be an inlet for medium to be treated, and the second opening within the housing may be a drain for the medium to be treated, or vice versa. Furthermore, in this embodiment, both electrodes each have an opening in its electrode surface, preferably centrally located, and be inlet and / or outlet opening, wherein the housing preferably has an outlet or inlet opening, or is closed. In embodiments in which both the first electrode surface and the opposing second electrode surface each have an aperture for passage of medium, the flow of the medium is preferably rectified with respect to the gap between the electrodes and the housing has an opening, e.g. B. is the flow of the medium from the space directed into both openings and the opening of the Ge Housing is inlet port, or the flow of the medium is directed through both openings in each case on the opposite electrode in the intermediate space and the opening of the housing is outlet opening.

If from the opposing first and second electrode surfaces only the first electrode surface has an opening for Inlet or outlet of medium and the spaced parallel second Electrode surface is closed, with optional section the closed second electrode surface of an insulator is formed, the second electrode at a distance from the second electrode surface one or more openings, also called second openings can be designated to have the passage of medium, and thus at a distance from the opposite ones Electrode surfaces allow the passage of medium.

The The device according to the invention therefore has at least in a first of the two spaced parallel electrode surfaces a first opening for passage of medium up, and optional in the electrically non-conductive housing, in which the two electrode surfaces are arranged, a second opening for the passage of Medium, and optionally an opening in the second electrode surface for the passage of medium or a second opening in the second electrode in one Distance to the second electrode surface.

The opening in the first electrode surface and the optional opening in the second electrode surface are preferably central arranged, wherein the electrode surfaces are preferably rotationally symmetrical are arranged around the center of the first opening. The electrode surfaces can congruent with each other Alternatively, the first electrode surface may have a have larger or smaller outer circumference, as the second electrode surface. Preferably both have Electrode surfaces have a circular outer circumference.

The inventive device provides by their Arrangement of the electrode surfaces an electric field Application of a voltage between the two electrode surfaces ready, which extends between the electrode surfaces. The medium as it passes through the gap between the electrode surfaces and passing through the opening of the first electrode surface at least in sections parallel to the opposite one another Electrode surfaces is moved, is the electric field between the electrodes approximately perpendicular to the flow direction of the medium is oriented between the electrodes.

The second electrode surface may be annular disk-shaped be and have an opening for the passage of medium, or insulating material against the opening of the first electrode surface, preferably around the Center of the second electrode surface, so that the second Electrode surface a substantially liquid-tight closed surface is.

at closed second electrode surface and arrangement of a second opening in the housing in which the first and second electrode surface are arranged, or in arrangement at least one second opening within a section the second electrode at a distance from the second electrode surface, which is disposed within the housing, the device be used for continuous treatment. Even with the arrangement of Electrode surfaces within a housing, the a container with volume for receiving medium is, can the device for quasi-continuous or sentence-wise treatment can be used by medium, and medium can through the first opening in the first electrode surface in the housing or be let out of the case.

The first electrode has one connected to the first opening first line path for supply or discharge of medium on, as well preferably one electrically separate from the first electrode or isolated, or an electrically non-conductive first Line connected to the first line path.

In Embodiments in which the second electrode has an opening in the second electrode surface, the second one has Electrode connected to this opening second Conduit for supply or discharge of medium. In embodiments, in which the second electrode has a closed second electrode surface and at a distance from the second electrode surface one or more recesses, the second electrode has one with them Recesses connected second conduction path for supply or discharge from medium. The second conductive path of the second electrode is preferably for feeding or discharging medium with a electrically isolated or isolated from the second electrode, or an electrically non-conductive second line connected.

Detailed description of the invention

The Invention will now be described in more detail with reference to the figures, in which

1 shows a schematic structure of an embodiment of the invention,

2 schematically shows an alternative construction of a device according to the invention,

3 schematically shows a further structure of a device according to the invention,

and 4 schematically shows an embodiment of the device according to the invention in a container.

In the same reference numerals designate functionally identical elements. Features described with respect to an embodiment can also be transferred to the other embodiments become.

In the embodiments of the invention, the inventive arrangement causes an opening 7 in the first electrode area 5 the first electrode 3 along with the parallel spaced arrangement of the second electrode surface 6 the second electrode 4 in that medium flowing through the opening in the first electrode surface, the gap 8th flows through, between the first electrode surface 5 and the second electrode surface 6 is clamped, and thus at between the first electrode 3 and second electrode 4 applied high-voltage pulses through the generated voltage field occurs. By the arrangement of the electrode surfaces 5 . 6 For example, in a housing 2 are arranged at a distance from the wall, it is avoided that electrically non-conductive material as insulation and / or as a wall portion of the housing 2 between the two electrodes 3 . 4 is to be arranged in the region of their gap. As a result, the breakdown of voltage between the electrodes 3 . 4 , or between the electrode surfaces 5 . 6 For example, in gas bubbles in the liquid medium, not to an effect on an insulation, the z. B. in devices according to the prior art, separating between the electrodes is arranged.

The Arrangement of an opening for the passage of medium in the Space between the parallel and spaced electrode surfaces becomes a uniform treatment of the medium achieved with the homogeneous electric field, which is between the opposite electrode surfaces formed. Areas of lower field strengths are therefore avoided and a lower energy input than with known devices is sufficient to treat equally effective of the medium.

1 shows a high voltage pulse generator 1 who is in a housing 2 arranged first electrode 3 and second electrode 4 supplied with high voltage pulses. The cables from the high voltage pulse generator 1 to the spaced apart electrodes 3 . 4 are outside the case 2 guided.

The first electrode 3 has a first electrode surface 5 on, at a distance and parallel to the second electrode surface 6 the second electrode 4 inside the case 2 is arranged. The first electrode 3 and second electrode 2 can through the wall of the housing 2 be guided, and outside the housing 2 be contacted by lines connected to the high voltage pulse generator 1 are connected.

The first electrode 1 points in its first electrode surface 5 a first opening 7 on, through the medium into the gap 8th , or from the gap 8th can flow, that of the first electrode surface 5 and the second electrode surface 6 is limited.

Accordingly, the first electrode 1 a recess on, as the first conduction path 9 to the opening 7 leads. At the first conduction path 9 is outside the case 2 an electrically non-conductive line 10 from an electrically non-conductive or electrically from the first conduction path 9 isolated material connected.

According to the invention, the second electrode surface 6 be a closed surface, or, as in 1 shown, the second electrode surface 6 can an opening 11 exhibit, the passage of medium from or into the space 8th serves. A recess in the second electrode 4 serves as a second conduction path 12 to the passage of medium, with the opening 11 in the second electrode area 6 connected is. Adjacent to the second conduction path 12 the second electrode 4 is an electrically non-conductive or electrically from the second conduction path 12 isolated wire 13 connected. As indicated by the arrows, it is preferred that in the method of the invention, medium 17 each with respect to the gap 8th rectified by the opening 7 in the first electrode area 5 and through the opening 11 in the second electrode area 6 passes, either on the gap 8th to or from the gap 8th path.

Alternatively, but less preferably, in the process, medium 17 through the first opening 7 in the gap 8th flowed out and out of the opening 11 in the second electrode area 6 from the gap 8th directed away, the housing 2 the first electrode and the second electrode without further opening receives.

In terms of the gap 8th rectified flow of medium 17 through the opening 7 in the first electrode area 5 and through the opening 11 in the second electrode area 6 shows the case 2 an opening 14 for the passage of medium 17 on, through the first conduction path 9 and the second conduction path 12 each same aligns with the case 2 flows, or out of the case 2 flows. Depending on the internal volume of the housing 2 can its opening 14 to pressure equalize while the housing 2 the first and second electrodes 3 . 4 includes liquid-tight, for example, with simultaneous removal of the medium from the housing 2 through the first opening 7 and the second opening 11 , or with simultaneous filling of the housing 2 through the first opening 7 and second opening 11 ,

2 shows a preferred embodiment of the invention, in which the second electrode surface 6 the second electrode 4 has a closed surface. In this embodiment, only the first electrode 3 an opening 7 in their first electrode surface 5 on, by means of the first line path 9 Medium in the gap 8th or from the gap 8th can flow. The second electrode surface 6 may be made of electrically conductive material throughout, or alternatively in the surface portion 15 made of non-conductive material, preferably opposite the opening 7 is arranged so that first electrode surface 5 an opening 7 and the second electrode surface 6 a spaced non-conductive portion 15 , wherein preferably the non-conductive surface portion 15 the second electrode surface 6 congruent with the first opening 7 is.

As the flow path for medium for a continuous process for the treatment of the medium, the housing 2 preferably an outlet or inlet opening 14 on. Preferably, an inlet or outlet port 14 of the housing 2 if present, in all embodiments of the invention in a housing portion above the gap 8th arranged to empty the gap between the first electrode surface 5 the second electrode surface 6 to avoid.

3 shows a development of the embodiment of 2 in that the second electrode 4 a second conduction path 12 while the housing 2 the first electrode 3 and second electrode 4 and otherwise closed in itself, or at least for the implementation of the method is closable, and optionally a pressure compensation device (not shown), so that the volume of the housing 2 as well as the gap 8th for the medium to be treated 17 only through the first conduction path 9 within the first electrode 3 and the second conduction path 12 within the second electrode 4 is accessible. The second electrode 4 has at least one, preferably two, three, four or more rotationally symmetrical about their longitudinal axis arranged recesses or holes 16 on, at a distance to the second electrode surface 6 are arranged and a passage for medium between the second conduction path 12 and the volume of the housing 2 produce.

4 shows an embodiment, in particular for the treatment of medium in the introduction into a housing 2 or discharge from a housing 2 is usable, which z. B has a volume as a storage or buffer tank or mixing tank for medium 17 serves. The first electrode 3 has a central in the first electrode surface 5 arranged opening 7 on, the second electrode 4 a closed second electrode surface 6 , which consists entirely of electrically conductive material. The arrangement of the first and second electrode surfaces 5 . 6 is preferably horizontal, to a non-gravitationally uniform distribution of medium in the space 8th to create. Inlet or outlet of medium is through the first conduit path 9 within the first electrode 3 in the opening 7 empties. The first electrode 3 is outside the case 2 by means of an electrical line to the high voltage pulse generator 1 connected. An insulation against the second electrode 4 already takes place through the formation of the housing 2 made of electrically non-conductive material, preferred is the first electrode 3 outside the case 2 provided with an outer insulation (not shown). For feeding (arrow) or removal of medium 17 is the first electrode 3 with an electrically non-conductive cable 10 connected.

The second electrode 4 is outside the case 2 by means of a line with the high voltage pulse generator 1 connected and to avoid uncontrolled currents except for the second electrode surface 6 at least inside the case 2 electrically isolated.

LIST OF REFERENCE NUMBERS

1

High voltage pulse generator

2

casing

3

first electrode

4

second electrode

5

first electrode area

6

second electrode area

7

first opening

8th

gap

9

first line path

10

first management

11

opening

12

second line path

13

second management

14

opening

15

Not conductive surface section

16

recess

17

medium

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 2005/093037 A1 [0004]
• - DE 60933273 T2 [0005]
• - EP 1123662 B1 [0006]

Cited non-patent literature

• - Lelieveld et al. (Food Preservation by Pulsed Electric Fields, CRC Press, p. 73, (2007)) [0009]

Claims (21)

Device for the treatment of a liquid medium ( 17 ), which has at least a first opening ( 7 ) for the passage of the medium ( 17 ) and within an electrically non-conductive housing ( 2 ) a first electrode ( 3 ) with a first electrode surface ( 5 ) and a second electrode ( 4 ) with a to the first electrode surface ( 5 ) parallel and spaced second electrode surface ( 6 ), characterized in that the first opening ( 7 ) in the first electrode surface ( 5 ) and the first electrode ( 3 ) a first conduction path ( 9 ) having an electrically isolated line ( 10 ) with the first opening ( 7 ) in the first electrode surface ( 5 ) connects. Apparatus according to claim 1, characterized in that the second electrode surface ( 6 ) is a self-contained surface. Device according to one of the preceding claims, characterized in that the first opening ( 7 ) centrally in the first electrode surface ( 5 ) is arranged. Device according to one of the preceding claims, characterized in that the first electrode surface ( 5 ) and / or the second electrode surface ( 6 ) has a circular outer periphery. Device according to one of the preceding claims, characterized in that the second electrode surface ( 6 ) is annular and in a surface section ( 15 ) opposite the opening ( 7 ) of the first electrode surface ( 5 ) consists of an electrically non-conductive material. Device according to one of the preceding claims, characterized in that the first electrode ( 3 ) and the second electrode ( 4 ) liquid-tight through the wall of the housing ( 2 ) and the first electrode surface ( 5 ) and the second electrode surface ( 6 ) at a distance from the wall of the housing ( 2 ) are arranged. Device according to one of the preceding claims, characterized in that the housing ( 2 ) an opening ( 14 ) for the passage of medium ( 17 ) having. Device according to one of the preceding claims, characterized in that the second electrode ( 4 ) a second conduction path ( 12 ) and at a distance to the second electrode surface ( 6 ) within the housing ( 2 ) at least one recess ( 16 ) for the passage of medium ( 17 ) connected to the second conduction path ( 12 ) connected is. Device according to one of claims 1 to 6, characterized in that the second electrode surface has an opening ( 11 ) for the passage of the medium and an opening connected thereto ( 11 ) second conduction path ( 12 ) having. Apparatus according to claim 8, characterized in that the device is set up, medium rectified by the first opening ( 7 ) in the first electrode surface ( 5 ) and the second opening ( 11 ) in the second electrode surface ( 6 ) in relation to the space ( 8th ) between the first electrode surface ( 5 ) and the second electrode surface ( 6 ) to flow. Device according to one of claims 7 to 9, characterized in that the second conduction path ( 12 ) following the second electrode with an electrically isolated second line ( 13 ) connected is. Method for treating liquid media by high-voltage pulse discharge by applying high-voltage pulses to a first electrode ( 3 ) with a first electrode surface ( 5 ) and a second electrode ( 4 ) with a to the first electrode surface ( 5 ) parallel and spaced second electrode surface ( 6 ), characterized in that the medium through a first opening ( 7 ) in the first electrode surface ( 5 ) into the space ( 8th ) or from the intermediate space ( 8th ) flowing from the first electrode surface ( 5 ) and the second electrode surface ( 6 ) is limited. Method according to claim 12, characterized in that the first electrode surface ( 5 ) and / or the second electrode surface ( 6 ) have a circular outer periphery. Method according to one of claims 12 or 13, characterized in that the second electrode surface ( 6 ) has a closed surface. Method according to one of claims 12 to 14, characterized in that the second electrode surface ( 6 ) is annular and in its surface section ( 15 ), opposite the first opening ( 7 ) is in the first electrode surface is formed by an electrically non-conductive material. Method according to one of claims 12 to 14, characterized in that the second electrode surface ( 6 ) is annular and one with a second conduction path ( 12 ) connected opening ( 11 ) to the passage of medium, and medium ( 17 ) through the first opening ( 7 ) in the first electrode surface ( 5 ) and through the opening ( 11 ) in the second electrode surface ( 6 ) in relation to the space ( 8th ) rectified flows from the first electrode surface ( 5 ) and the second electrode surface che ( 6 ) is limited. Method according to one of claims 12 to 16, characterized in that the first electrode surface ( 5 ) and the second electrode surface ( 6 ) in a non-conductive housing ( 2 ) at a distance to the wall of the housing ( 2 ) are arranged. Method according to one of claims 12 to 17, characterized in that the medium ( 17 ) through an opening ( 14 ) in the housing ( 2 ) passes. Method according to one of claims 12 to 18, characterized in that the medium is pumpable. Method according to one of claims 12 to 19, characterized in that the medium is lumpy components having. Use of a method according to one of the claims 12 to 20 for the reduction of the germ content and / or the Zellausluß of Food.

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