Filtration media especially useful for filtering fluids associated with wire electron discharge machining (WEDM) processes

A method of making a fibrous web comprising:

• (a) forming a wet-laid fibrous web from an aqueous fibrous slurry comprised of about 20 wt. % to about 80 wt. %, based on total weight of the wet-laid fibrous web, sheath-core bicomponent staple fibers, and from about 10 wt. % to about 50 wt. %, based on total weight of the wet-laid fibrous web, fibrillated lyocell staple fibers;
• and
• (b) subjecting the wet-laid sheet from step (a) to hot calendering to melt the sheath of the bicomponent staple fibers so as to bind the fibrillated lyocell staple fibers one to one another and achieve a fibrous filtration media having a wet burst strength of 3 bar or greater and a mean flow pore size of 20 μm or less, wherein the media is free of binder resin.