The permeation membrane element utilizes a short film structure, increasing the number of membrane layers to significantly enhance membrane efficiency, providing economical, stable, and superior membrane elements for water treatment systems. The BW series is available in two models: 8 inches and 4 inches, widely applicable in various fields such as brackish water desalination, thermal power plant boiler feedwater, surface water, and zero-liquid discharge wastewater in the petroleum and petrochemical industries. The BW brackish water series membrane elements operate at low pressure and exhibit high removal rates for difficult-to-treat soluble salts like TOC and SiO2, offering a more cost-effective solution for industrial applications.
Reverse osmosis membrane is a thin film that selectively allows substances to pass through, called a semi permeable membrane. Generally, a thin film that can only pass through solvents and cannot pass through solutes is called an ideal semi permeable membrane. When dilute solutions (such as fresh water) and concentrated solutions (such as saltwater) of the same volume are placed on both sides of a semi permeable membrane, the solvent in the dilute solution will naturally pass through the semi permeable membrane and flow spontaneously towards the concentrated solution side. This phenomenon is called permeation.
When the permeation reaches equilibrium, the liquid level on the concentrated solution side will be higher than that of the dilute solution by a certain height, forming a pressure difference, which is the osmotic pressure. The magnitude of osmotic pressure depends on the inherent properties of the solution, which are related to the type, concentration, and temperature of the concentrated solution and independent of the properties of the semi permeable membrane. If a pressure greater than the osmotic pressure is applied to the concentrated solution side, the direction of solvent flow will be opposite to the original osmotic direction, starting to flow from the concentrated solution to the dilute solution side. This process is called reverse osmosis.