Voltea’s award-winning desalination technology, CapD-I (Capacitive deionization), desalinates brackish water at a lower economic and environmental cost than any other available technology. CapD-I is a simple and innovative way to remove dissolved salts from water, helping to unlock the world’s water potential.
CapD-I is the result of more than ten years of academic and commercial R&D. Voltea, which owns global patents to CapD-I, is a Unilever spin-off based in the Netherlands. Voltea has recently closed an investment round for commercial development, with investors including Pentair, Rabo Ventures and Unilever Ventures.
CapD-I moves water through an electrical field, using electrodes to attract dissolved ions such as sodium, calcium, chloride, nitrates and arsenic. It then reverses the field to regenerate and uses selective membranes to trap the released ions in a waste stream for removal. This:
- recovers between 80% and 90% of the water, reducing water consumption;
- prevents fouling of the electrodes, eliminating the need for anti-scaling and biofouling chemicals;
- reuses the energy stored in the electrodes during desalination, reducing energy use;
- involves little maintenance or down-time;
- is extremely cost effective compared to existing technologies.
CapD-I is scalable, with numerous industrial and domestic applications, including softening of tap water, desalination of process water, brackish ground water and cooling towers.
In cooling towers, one of Voltea’s first applications, CapD-I reduces use of make-up water by 20%, blow-down water by up to 60% and chemicals by up to 80%. CapD-I can also eliminate scaling and corrosion problems in a critical heat exchanger by running a lower cycle of concentration, reducing scaling ions and corrosive chlorides and sulphates. And it is risk-free and easy to install, since it does not alter the chemical composition of cooling water.
