Needle felt:Our PTFE Coated Polyester Needle Felt can nearly retain all the particles in the dust gas Needle feltPTFE coated( ... compare with.Applications: 1) Mineral: cement, gypsum, lime, carbon black, asbestos, limestone, phosphate, alkali2) Chemicals: acids, alkalis ... asphalt plant, aster, incinerator, metallurgy,cement, lime, carbon black, liquid boiler, coal fire boilerPTFE Filter Bag,Filter ...