Needle punched nonwoven fabric is made from various fibrous webs (usually carded webs) in which fibers are bonded together mechanically through fiber entanglement and frictions after fine-needle barbs repeatedly penetrated through the fibrous web. The performance of needle-punched nonwoven, including filtration efficiency, pressure drop, operational life, cleaning performance, dust cake formation, and mechanical and chemical resistance, are influenced by its fiber sizes, fabric porosity, thickness, and fabric permeability