Nanofiltration (NF) is a pressure-driven membrane separation process between reverse osmosis and ultrafiltration. The pore size of nanofiltration membrane is about several nanometers. Nanofiltration membrane is mostly derived from reverse osmosis membrane, such as CA, CAT membrane, aromatic polyamide complex

Sealing ring → central pipe water inlet membrane and sulfonated polyethersulfone membrane, etc. However, compared with reverse osmosis, its operating pressure is lower, so nanofiltration is also called "low pressure reverse osmosis" ⑩

-Inflow splitter or "LooseRO".