Composite porous media
A composite porous media for either gas or liquid flow is strong and efficient, and can readily be formed in or into a wide range of different shapes and configurations. In particular, the porous media is a composite of a metal, aerogel or ceramic foam (i.e., a reticulated inter-cellular structure in which the interior cells are interconnected to provide a multiplicity of pores passing through the volume of the structure, the walls of the cells themselves being substantially continuous and non-porous, and the volume of the cells relative to that of the material forming the cell walls being such that the overall density of the intercellular structure is less than about 30 percent theoretical density) the through pores of which are impregnated with a sintered powder or aerogel. The thickness, density, porosity and porous characteristics of the final composite porous media can be varied to conform with what is demanded by the intended use.
1. A composite porous media filter comprising:
a conduit having an inlet for receiving a fluid and an outlet for providing a filtered fluid; and
within the conduit a composite porous media including a foam having a reticulated, inter-cellular structure with a multiplicity of interconnected pores extending therethrough; and sintered powder impregnating pores of the foam.
2. The filter of claim 1 , wherein the foam is a ductile metal foam.
3. The filter of claim 1 , wherein the foam and the powder are made of metal.
4. The filter of claim 3 , wherein each of the foam and the powder is one of stainless steel, nickel, titanium, zirconium, and a nickel alloy.
5. The filter of claim 1 , wherein one of the foam and the powder is made of ceramic.
6. The filter of claim 1 , wherein one of the foam and the powder is made of an aerogel.
7. The filter of claim 1 , wherein the composite porous media includes a layer of sintered powder defining a surface of the media.
8. The filter of claim 7 , wherein the layer has a thickness in the range of about 10% to about 50% of the total thickness of the media.
9. The filter of claim 7 , wherein the layer has a thickness in the range of about 25% to about 75% of the total thickness of the media.
10. The filter of claim 1 , wherein the foam has a density less than about 15% of theoretical density.
11. The filter of claim 10 , wherein the foam has a density less than about 10% of theoretical density.
12. The filter of claim 1 , wherein the composite porous media has a density in the range of about 20% to about 35% of theoretical density.
13. The filter of claim 1 , wherein the foam has in the range of 10 to 150 pores per inch.
14. The filter of claim 13 , wherein the sintered powder in the pores provides a porous structure having pores with a nominal size in the range of about 100 micrometers to about 0.1 micrometers.
15. The filter of claim 1 , wherein the conduit includes a cylindrical tube.
16. The filter of claim 1 , wherein the composite porous media is in the form of a cylinder.
17. The filter of claim 16 , wherein the composite porous media includes a layer of sintered powder defining at least one of the inner and outer cylindrical surfaces of the cylinder.
18. The filter of claim 17 , wherein the layer has a thickness in the range of about 10% to about 50% of the total wall thickness of the cylinder.
19. The filter of claim 17 , wherein the layer has a thickness in the range of about 25% to about 75% of the total wall thickness of the cylinder.