Nanofiltration (NF) equipment設(shè)備（NFNanofiltration (NF) equipment is a pressure-driven membrane separation process that falls between reverse osmosis and ultrafiltration, with nanofiltration membrane pore sizes typically in the range of a few nanometers. The membrane modules for nanofiltration systems were commercialized in the mid-1980s. Most nanofiltration membranes are derived from reverse osmosis membranes, such as cellulose acetate (CA), cellulose triacetate (CTA), aromatic polyamide composite membranes, and sulfonated polyethersulfone membranes. However, compared to reverse osmosis, nanofiltration systems operate at lower pressures, which is why NF equipment is also referred to as "low-pressure reverse osmosis" or "loose reverse osmosis (Loose RO)."Nanofiltration (NF).

Nanofiltration equipment is widely applied in industries such as electronics, food, and pharmaceuticals for practical separation processes including ultrapure water production, high-concentration juice processing, separation of peptides and amino acids, antibiotic concentration and purification, whey protein concentration, and NF membrane-bioreactor coupling67. Compared to ultrafiltration (UF) or reverse osmosis (RO) systems, NF exhibits lower retention of monovalent ions and organic compounds with molecular weights below 200, while achieving high removal rates for divalent/multivalent ions and organic substances with molecular weights between 200–5008. This characteristic makes NF particularly suitable for water softening, purification, and the separation, classification, and concentration of substances with molecular weights in the hundreds (e.g., dyes, antibiotics, peptides, polysaccharides in chemical and bioengineering processes), as well as decolorization and deodorization16. NF systems are primarily used in drinking water treatment to remove hardness components (e.g., Ca2?, Mg2?), trihalomethane intermediates, odors, colorants, pesticides, synthetic detergents, soluble organic compounds, and evaporation residues7. Additionally, NF plays a critical role in industrial applications such as high-purity water preparation for electronics, precision separation in pharmaceuticals, and concentration processes in food production

Nanofiltration Process Flow

Source Water → Source Water Pump → Mechanical Filter → Activated Carbon Filter → Precision Filter → High-Pressure Pump → NF Main Filtration System