Depending upon their pore size and upon the hydraulic pressure required for the separation, the four membrane systems commonly in use for the treatment of drinking water are detailed in the following table:
Pore size | Pressure (bar) | |
---|---|---|
Microfiltration | 0.1 - 1 μm | 0.1 - 2 |
Ultrafiltration | 5 nm - 0.1 μm | 0.1 - 5 |
Nanofiltration | 1 - 5 nm | 5 - 15 |
Reverse osmosis | < 1 nm | 8 - 50 |