Woven metal fiber diesel particulate filter

Abstract

A passive particulate filter assembly for filtering diesel exhaust. The assembly includes a housing unit defining a filtering chamber having an inlet port and an outlet port. A cylindrical inner core member is disposed in the filtering chamber and is surrounded by a pleated cylindrical filter pack having first and second opposite ends. An end cap couples with the first end of the filter pack and is configured to prevent exhaust flow there through. An end plate is coupled to the second end of the filter pack and is configured to secure the filter pack to the housing unit. The filter pack comprises a woven metal fiber medium preferably manufactured from stainless steel or a nickel-chromium-iron alloy having a porosity of between about 2 to about 15 μm.

Description

DRAWINGS

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

FIG. 1 illustrates an exploded perspective view of a passive particulate filter system for diesel exhaust according to the present disclosure;

FIG. 2 illustrates a perspective view of a filter assembly;

FIG. 3 is a cross-sectional view of FIG. 2 and illustrates the inner core member in addition to the end cap and end plate;

FIG. 4 is a side view of a pleated filter pack;

FIG. 5 is a cross-sectional view of FIG. 4;

FIG. 6 is a partial magnified view of FIG. 5;

FIG. 7 is a plan view of a flanged end plate;

FIG. 8 is a cross-sectional view of FIG. 7;

FIG. 9 is a partial magnified view of FIG. 8;

FIG. 10 is a plan view of an end cap;

FIG. 11 is a cross-sectional view of FIG. 10; and

FIG. 12 is a partial magnified view of FIG. 11.

Claims

1. A passive diesel particulate filter assembly comprising: a housing unit defining a filtering chamber having an inlet port and an outlet port;a cylindrical inner core member disposed in the filtering chamber;a pleated cylindrical filter pack having first and second opposite ends and surrounding the inner core member;an end cap coupled to the first end of the filter pack and configured to prevent exhaust flow there through; andan end plate coupled to the second end of the filter pack and configured to secure the filter pack to the housing unit;wherein the filter pack comprises a woven metal fiber medium.

2. A filter assembly according to claim 1, wherein the filter pack comprises woven sintered metal fibers having an average porosity of between about 2 to about 15 μm.

3. A filter assembly according to claim 1, wherein the filter pack is manufactured of a material selected from the group consisting of nickel-chromium-iron alloy and stainless steel.

4. A filter assembly according to claim 1, wherein the filter pack comprises a dual laminate woven material having an exterior layer and an interior layer.

5. A filter assembly according to claim 4, wherein the exterior layer has an exterior porosity and the interior layer has an interior porosity different than the exterior porosity.

6. A filter assembly according to claim 5, wherein an average exterior porosity is between about 7 to about 15 μm and an average interior porosity is between about 2 to about 7 μm.

7. A filter assembly according to claim 1, wherein the housing unit comprises an inlet housing coupled to an outlet housing.

8. A filter assembly according to claim 1, configured to operate having a fuel penalty of less than about 3%.

9. A filter assembly according to claim 1, having a soot loading capability of between about 0.5 g/l to about 4 g/l.

10. A filter assembly according to claim 1, further comprising at least one weld strap circumferentially disposed about the filter pack and configured to secure the filter pack to the inner core member.

11. A filter assembly according to claim 1, wherein the filter pack comprises at least 150 folds and has a surface area greater than about 7 ft2.

12. A filter assembly according to claim 1 configured such that the diesel exhaust travels from the inlet port into the filtering chamber and passes inwardly through the cylindrical filter pack to an interior of the inner core member and exits through the outlet port.

13. A passive diesel particulate filter assembly comprising: a housing unit defining a filtering chamber having an inlet port and an outlet port;a perforated cylindrical inner core member disposed in the filtering chamber;a pleated cylindrical filter pack comprising a dual layer woven sintered metal fiber medium surrounding the inner core member and having first and second opposite ends, the innermost layer having an average porosity of between about 2 to about 7 μm and the outermost layer having an average porosity of between about 7 to about 15 μm;an end cap coupled to the first end of the filter pack and configured to prevent exhaust flow there through; anda flanged end plate coupled to the second end of the filter pack and configured to secure the filter pack to the housing unit;wherein the filter assembly is configured such that the diesel exhaust travels from the inlet port into the filtering chamber and passes inwardly through the dual layer filter pack to an interior of the inner core member and exits through the outlet port.

14. A filter assembly according to claim 13, configured to configured to operate having a fuel penalty of less than about 3%.

15. A filter assembly according to claim 13, wherein the woven sintered metal fiber medium is manufactured of a material selected from the group consisting of nickel-chromium-iron alloy and stainless steel.

16. A filter assembly according to claim 13, wherein the filter pack comprises at least 150 folds and has a surface area greater than about 7 ft2.

17. An exhaust gas filtering system for a diesel engine comprising: a passive diesel particulate filter assembly including a housing unit defining a filtering chamber having a cylindrical inner core member surrounded by a dual layer woven sintered metal fiber medium, wherein the innermost layer of the metal fiber medium has an average porosity of between about 2 to about 7 μm and the outermost layer of the metal fiber medium has an average porosity of between about 7 to about 15 μm; anda secondary injection assembly coupled to the housing unit and configured to selectively heat the diesel exhaust to a temperature suitable for regeneration of the passive diesel particulate filter.

18. A system according to claim 17, wherein the woven sintered metal fiber medium is manufactured of a material selected from the group consisting of nickel-chromium-iron alloy and stainless steel.

19. A system according to claim 17, wherein the filter assembly is configured such that the diesel exhaust travels into the filtering chamber and passes inwardly through the dual layer filter pack to an interior of the inner core member and exits through an outlet port.

20. A system according to claim 17, wherein the secondary injection assembly is configured to regenerate a loaded filter assembly with a maximum fuel penalty of about 3%.