Reverse osmosis (RO) and Nanofiltration (NF) membranes are commonly used as a filtration method to remove many types of dissolved solids (large molecules and ions) from solutions by applying pressure to the solution when it is on one side of a selective membrane. The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side.
Order Spare Parts and ConsumablesReduces water and sewage use costs
Especially when used instead of distillation for high-purity water production
Modular design for ease of installation
Reverse osmosis (RO) is a special type of filtration that uses a semi-permeable, thin membrane with pores small enough to pass pure water through while rejecting larger molecules such as dissolved salts (ions) and other impurities such as bacteria. Reverse osmosis is used to produce highly purified water for drinking water systems, industrial boilers, food and beverage processing, cosmetics, pharmaceutical production, seawater desalination, and many other applications. It has been a recognized technology for more than a century and commercialized since the 1960’s.
Reverse osmosis is a continuously operating treatment technology that uses pressure to pass source water through a thin membrane and thereby separate impurities from water.
View All Applications
There are key differences between reverse osmosis and nanofiltration membrane technology and conventional filtration (i.e. media filtration). The predominant removal mechanism in conventional filtration is straining, or size exclusion, so the process can theoretically achieve perfect exclusion of particles regardless of operational parameters such as influent pressure and concentration. Reverse osmosis, however, involves a diffusive mechanism so that separation efficiency is dependent on solute concentration, pressure, and water flux rate.
Reverse Osmosis is the reversal of this natural phenomenon, by the application of external pressure on the solution that contains the higher concentration of dissolved ions, thus forcing water through the semi-permeable membrane in the opposite direction, leaving behind the dissolved ions and the suspended solids. In the reverse osmosis process, the water that passes through the membrane is commonly referred to as permeate, or product water. The water that remains behind the membrane along with the dissolved and suspended solids is referred to as the reject, brine, or concentrate water.
Most applications looking for high salt rejection resulting in lower higher quality effluent typically utilize RO membranes. In some applications where high salt rejection is not required, Nanofiltration membranes (often referred to as softening membranes) can be used to selectively remove certain salts from the feed stream reducing the total dissolved solids to acceptable levels at lower operating pressures than RO membranes.
