polyester sewage treatment fabrics 1. used for belt filter press 2.good air & water permeability 3.steel clipper polyester sewage treatment ... treatment factories.They have the characteristics ofgood water permeability, air permeability and non-revealed sludge,acid-resisting, alkali-resisting, ... , the sludge can be peeled off easily after pigeonhole filter, so the screen are easily cleaned and have a ...