Electrically regeneratable filter element

1. An electrically regeneratable filter element, comprising at least two flanks comprising a stiff material layer and at least one thermally and electrically insulated side, said filter element comprising a metal fiber fleece being pleated according to pleating lines providing an edge with pleat openings, such that said metal fiber fleece is mounted between said flanks, said thermally and electrically insulated sides making contact with said edge, said thermally and electrically insulated sides closing said pleat openings, said metal fiber fleece comprising at least one metal fiber strip, each metal fiber strip having two ends, a contact body being fixed to each of said ends of said metal fiber strip, said contact bodies being brought together and being electrically insulated one from the other by an electrically insulating plate, said electrically insulating plate being inserted between said contact bodies.

2. An electrically regeneratable filter element as in claim 1 , at least one of said flanks having an aperture, said metal fiber fleece and flanks providing a hollow filter volume, said aperture providing entrance for gasses to to the inside of said hollow filter volume.

3. An electrically regeneratable filter element as in claim 2 , all of said flanks having an aperture.

4. An electrically regeneratable filter element as in claim 1 , wherein said flanks exercise a clamping force to said metal fiber fleece in a direction essentially parallel to said pleating lines.

5. An electrically regeneratable filter element as in claim 1 , wherein each of said flanks comprises a thermally and electrically insulating fabric and a stiff material layer, said thermally and electrically insulating fabric being present at one side of said stiff material layer, providing a thermally and electrically insulated side to said flank.

6. An electrically regeneratable filter element as in claim 1 , wherein each of said flanks comprises a ceramic plate, said metal fiber fleece being mounted between said ceramic plates of both flanks.

7. An electrically regeneratable filter element as in claim 1 , each of said flanks comprising a stiff material layer, said stiff material layer and said metal fiber fleece being connected using a layer of ceramic adhesive, said layer of ceramic adhesive preventing direct contact of said metal fiber fleece over the length of said edge of said metal fiber fleece with said flank.

8. A filter unit comprising electrically regeneratable filter elements as in claim 1 , said filter unit comprising a permeable core member extending through apertures of said flanks of said filter elements.

9. A filter unit as in claim 8 , said filter elements being thermally insulated from each other.

10. A filter unit as in claim 8 , said permeable core member being a perforated metal tube.

11. A filter system comprising at least one filter unit as in claim 8 , said filter system comprising a valve system and an electronic control system, said electronic control system controlling opening and closing of said valve system and said electronic control system controlling the provision of electric current to said filter elements of said filter units of said filter system.

12. A filter system as in claim 11 , said filter system comprising at least two filter units, said valve system putting one filter unit off-line, said electric current being provided to at least one filter element of said filter unit which is put off-line.

13. A filter element as in claim 1 , wherein said contact bodies are fixed to said electrically insulating plate.

14. A filter element as in claim 13 , wherein said contact bodies are fixed to said electrically insulating plate by means of bolts and nuts.

15. A filter element as in claim 14 , wherein mica sheets are provided for avoiding electrical contact between contact bodies and bolts.

16. A filter element as in claim 1 , wherein the contact bodies are nickel sheets.

17. A filter element as in claim 1 , wherein nickel sheets are sintered to the ends of the metal fiber fleeces for providing the contact bodies.

18. A filter element as in claim 1 , wherein said electrically insulating plate is a mica plate.