CDI - Capacitive Deionization
For water softening in residential or industrial applications
Membranes: standard grade and low electrical resistance membranes
Water softening or water demineralization removes scale forming ions like calcium and magnesium from hard water. This is important for the prevention of scale forming in:
- power stations
- cooling towers
- boiler feed water supplies
- point-of-entry household applications
A new, upcoming technology for water softening is capacitive deionization. Fujifilm developed cost effective membranes for this breakthrough technology.
The advantages of capacitive deionization
Capacitive deionization does not need salt dosing for regeneration like mixed bed technology. This is a big advantage for the surface water pollution level due to water softening processes. Another advantage is that uptime can be improved and maintenance intervals and costs can be lowered. Fujifilm develops cost effective membranes for water softening that are user friendly and robust, with a stable performance.
How does it work?
The feed solution flows in between a positive and negative electrode. Under the applied electric field the positive and negative ions move respectively to the negative and positive electrode. The ions are grasped by the ion capacitors. When the capacitors are saturated with ions, the polarity is reversed. Subsequently, the ions are thrust out and will be trapped between the membranes. The function of the E-separation membranes during regeneration is to prevent precipitation of the ions on the electrodes. After flushing away the ions, the cell is clean and can be used again.