Could electrodialysis be a feasible option for desalination?

Chile’s public and private sectors are looking into new options to boost desalination amidst environmental concerns surrounding reverse osmosis, the most widely used technology for the process. 

One option is electrodialysis, which is promoted by local startup Wind Energy Water, and consists of using electrodes to pull naturally occurring dissolved salts through an ion exchange membrane to separate the water from the salts.

Unlike reverse osmosis, which has been questioned because of its brine discharges, electrodialysis “doesn’t require chemicals nor filters, and doesn’t require maintenance nor professional chemical personnel,” Wind Energy Water’s CEO Vladimir De Kartzow told BNamericas.

The startup has met with representatives from water utilities, mining firms and the presidential delegate for Petorca province in Valparaíso region, Luis Soto.

This central province is one of the areas worst hit by the 13-year long drought affecting Chile.

When asked about brine discharges, De Kartzow said electrodialysis generates “minimum” brine, and that it would be used to extract subproducts such as table salt. 

One disadvantage would be desalination costs, since they would be double those of reverse osmosis at the start, but the CEO claims that they would be the same by the seventh year of operations since electrodialysis does not require the filters and chemicals used in reverse osmosis. 

While Chile is seen as a potential regional leader in desalination, some players within the industry have pointed out that it is not technically feasible to install plants along the entire coast, while others have cited long environmental permitting processes as major bottlenecks. 

At the same time, the industry is awaiting the results of the September 4 referendum on a new constitution, as the draft document would replace water rights with administrative permits, which would not entail property rights, and declare the sea a “common natural good.”