Most of these membranes have a wide range of pore sizes to choose from insuring the optimum separation for any application according to filtration spectrum. At one extreme, reverse osmosis membranes reject most dissolved compounds, including salts, while allowing water molecules to pass. Nanofiltration membranes have salt rejection ranging from 10% to 85% (these are sometimes referred to as water softening membranes). While Ultrafiltration membranes can reject molecules of sizes ranging from 1000 to 100,000 d.a. Microfiltration with pore sizes ranging from 0.05 micron to 3 microns are also available for coarse separations.

The standard modular size of a VSEP System is 450 to 1,500 square feet composed of discs with a 19 inch active diameter. Each disc element is manufactured and quality assured by Dunwell.

VSEP systems are supplied with internationally branded Programmable Logic Controllers. All components are fully contained in a NEMA 4 rated enclosure.

Various levels of control sophistication are available depending on the complexity of the application. For polishing or low solids applications simple controls having minimal outputs and inputs are provided. For high solids applications controls with more features are used to insure trouble free operation. The VSEP controller typically sets solids levels by actuating the exit valve based on operating parameters such as pressure or flow rate.

Other control options available include automatic clean-in-place, automatic flush, automatic shut down, full alarm features with digital diagnostic displays, remote diagnostics and monitoring, and many others. Dunwell engineers have spent years perfecting VSEP controls to maximize reliability and to minimize operator intervention.