HIGH DENSITY PERLITE FILTER AID
WEBThe method according to embodiment 1 or 2, wherein, before milling, the expanded perlite has a d 10 diameter less than 20 μm. 4. The method according to any of embodiments 13, wherein the filter aid has a permeability ranging from about darcy to about darcy and a cake density greater than 15 lb/ft 3. 5.