Ultrafiltration (UF) is a membrane separation technology driven by pressure difference, utilizing the high-precision interception capability of UF membranes for solid-liquid separation or the classification of substances with different molecular weights. Compared to reverse osmosis (RO) water treatment equipment, UF operates at lower pressures, resulting in lower equipment investment and operating costs. It involves no phase change, has low energy consumption, and offers high membrane selectivity. The principle of ultrafiltration water treatment involves using an asymmetric microporous structure and a semi-permeable membrane medium at room temperature under a certain pressure and flow rate. Relying on the pressure difference across the membrane as the driving force, filtration is carried out in a cross-flow manner. This allows solvents and small molecular substances to pass through, while macromolecular substances and fine particles such as proteins, water-soluble polymers, and bacteria are retained by the membrane. This achieves the goals of separation, classification, purification, and concentration, making it a new type of membrane separation technology.