FILTER MEDIA AND RELATED FOAM FORMING METHODS
Filter media and related methods of foam forming the filter media are generally described herein.
1 . A method of fabricating a filter media, comprising:
providing a fiber dispersion;
adding one or more foaming additives to the fiber dispersion;
forming a foam slurry comprising the fiber dispersion;
applying the foam slurry onto a carrier; and
drying the foam slurry, thereby providing the filter media.
2 . The method of claim 1 , wherein the foam slurry has a liquid fraction of greater than or equal to 2% and less than or equal to 90%.
3 . The method of claim 2 , wherein the liquid fraction of the foam slurry is greater than or equal to 5% and less than or equal to 60%.
4 . The method of claim 2 , wherein the liquid fraction of the foam slurry is greater than or equal to 20% and less than or equal to 50%.
5 . The method of claim 1 , wherein the fiber dispersion comprises cellulose fibers, nanocellulose fibers, microfibrillated cellulose fibrils, synthetic fibers, glass fibers, lyocell fibers, polyvinyl alcohol fibers, bicomponent fibers, tricomponent fibers, and/or combinations thereof.
6 . The method of claim 1 , wherein providing the fiber dispersion comprises forming the fiber dispersion in a pulper.
7 . The method of claim 1 , further comprising adding one or more binders to the fiber dispersion.
8 . The method of claim 7 , wherein the one or more binders comprise an acrylic, phenolic, melamine, epoxy, polyester, and/or particle binder.
9 . The method of claim 1 , wherein the one or more foaming additives comprise a surfactant.
10 . The method of claim 1 , wherein the one or more foaming additives comprise air.
11 . The method of claim 1 , wherein the foam slurry has a foam density of greater than or equal to 20 g/l and less than or equal to 800 g/l.
12 . The method of claim 11 , wherein the foam density of the foam slurry is greater than or equal to 30 g/l and less than or equal to 600 g/l.
13 . The method of claim 1 , wherein the carrier is a semi-continuous or continuous moving carrier.
14 . The method of claim 13 , wherein applying the foam slurry onto the semi-continuous or continuous moving carrier comprises flowing the foam slurry through a headbox, foam nozzle, curtain coater, and/or slot die.
15 . The method of claim 1 , wherein the filter media is a gas and/or a liquid filtration and/or separation media.
16 . The method of claim 1 , wherein drying the foam slurry comprises applying heat to the foam slurry.
17 . A filter media, comprising:
a fiber web comprising a plurality of pores,
wherein the filter media has a pore permeability index (PPI) of greater than or equal to 0.2 and less than or equal to 4.0, and wherein greater than or equal to 5% of pores of the plurality of pores have an average size of less than or equal to 1 micrometer.
18 . The filter media of claim 17 , wherein the PPI of the filter media is greater than or equal to 0.3 and less than or equal to 3.5.
19 . The filter media of claim 17 , wherein greater than or equal to 10% of the pores of the plurality of pores have the average size of less than or equal to 1 micrometer.
20 . The filter media of claim 17 , wherein less than or equal to 50% of the pores of the plurality of pores have the average size of less than or equal to 1 micrometer.
21 - 31 . (canceled)