Since 1980, Beaver Chemicals Limited has been a filteraid distributor. We provide filtering expertise to virtually all areas of industry. Filteraids are mineral powders or cellulose fibers or a combination of both, used to filter suspended matter from all types of liquids, aqueous and non aqueous. Filteraids are generally classified as to how small a particle they can remove from a liquid. Natural diatomaceous earth (also known as diatomite ) removes particles as small as 0.45 microns.