Co-agglomerated composite materials
A composite filter aid may include diatomaceous earth, natural glass, and a precipitated silica binder, wherein the filter aid has a permeability ranging from 3 to 20 darcys. A composite filter aid may include diatomaceous earth, perlite, and a precipitated silica binder, wherein the filter aid has an alpha density less than 15 lbs/ft 3 . A method for making a composite material may include blending diatomaceous earth and perlite, adding alkali silicate to the blended diatomaceous earth and perlite, and precipitating the alkali silicate as a binder to make the composite material. A method for filtering a beverage may include using a composite filter aid and/or composite material.
1. A composite filter aid comprising co-agglomerated particles that comprise:
diatomaceous earth;
natural glass; and
1% to 5% by weight of an alkali silicate binder, with respect to the total weight of the co-agglomerated particles;
wherein the average particle size of the diatomaceous earth ranges from 5 microns to 200 microns; and
wherein the average particle size of the natural glass ranges from 5 microns to 200 microns.
2. The composite filter aid of claim 1 , wherein the filter aid has a permeability ranging from 5 darcys to 16 darcys.
3. The composite filter aid of claim 1 , wherein the filter aid has a permeability ranging from 15 darcys to 20 darcys.
4. The composite filter aid of claim 1 , wherein the diatomaceous earth comprises calcined diatomaceous earth, flux calcined diatomaceous earth, or a mixture thereof.
5. The composite filter aid of claim 1 , wherein the natural glass comprises at least one of perlite, volcanic ash, pumice, shirasu, obsidian, pitchstone, or rice hull ash.
6. The composite filter aid of claim 1 , wherein the co-agglomerated particles have a d 50 diameter ranging from 30 microns to 70 microns.
7. The composite filter aid of claim 1 , wherein the co-agglomerated particles have a d 90 diameter ranging from 80 microns to 120 microns.
8. The composite filter aid of claim 1 , wherein the filter aid has a ratio of the diatomaceous earth to the natural glass ranging from 1:3 to 3:1 by weight.
9. The composite filter aid of claim 1 , wherein the filter aid has a BET surface area ranging from 5 m 2 /g to about 50 m 2 /g.
10. The composite filter aid of claim 1 , wherein the diatomaceous earth has a median pore size ranging from 5 microns to 35 microns.
11. The composite filter aid of claim 1 , wherein the diatomaceous earth has a surface area ranging from 5 m 2 /g to 40 m 2 /g.
12. The composite filter aid of claim 1 , wherein the filter aid has a porosity ranging from 3 liters per milligram to 7 liters per milligram.
13. The composite filter aid of claim 1 , wherein the filter aid has a beer soluble iron content of less than 5 ppm, as measured by the American Society of Brewing Chemists (ASBC) method.
14. The composite filter aid of claim 1 , wherein the filter aid has a beer soluble iron content of less than 1 ppm, as measured by the ASBC method.
15. The composite filter aid of claim 1 , wherein the filter aid has a cristobalite content of less than 6% by weight.
16. The composite filter aid of claim 1 , wherein the filter aid has a cristobalite content of less than 1% by weight.
17. The composite filter aid of claim 1 , wherein the filter aid has an alpha density ranging from 9 lbs/ft 3 to 15 lbs/ft 3 .
18. The composite filter aid of claim 1 , wherein the filter aid has a permeability ranging from 2 darcys to 20 darcys.
19. A composite filter aid comprising co-agglomerated particles that comprise:
diatomaceous earth having a d 50 diameter ranging from 20 microns to 70 microns;
perlite having a d 50 diameter ranging from 15 microns to 80 microns; and an alkali silicate binder;
wherein the co-agglomerated particles have a d 50 diameter ranging from 30 microns to 70 microns;
wherein the filter aid has a wet density of less than 15 lbs/ft 3 ; and
wherein the average particle size of the diatomaceous earth ranges from 5 microns to 200 microns; and
wherein the average particle size of the perlite ranges from 5 microns to 200 microns.
20. A method for making a co-agglomerated material, the method comprising:
blending diatomaceous earth and perlite in a weight ratio of diatomaceous earth to perlite of 1:3 to 3:1;
adding alkali silicate to the blended diatomaceous earth and perlite;
precipitating the alkali silicate as a binder that binds the diatomaceous earth and the perlite together to make the co-agglomerated material; and
wherein the average particle size of the diatomaceous earth ranges from 5 microns to 200 microns; and
wherein the average particle size of the perlite ranges from 5 microns to 200 microns.
21. The method of claim 20 , wherein the weight ratio of diatomaceous earth to perlite is 1:3.