Evaluation Of Electrodialysis For Brine Management Inland Brackish Desalination

Electrodialysis (ED) can become a key technology for treating brine obtained during desalination with reverse osmosis (RO). Brine disposal can pose as a challenge specially within inland desalination facilities, due to the high salinity content of brine usually discharge in any form can have environmental impacts. This investigation provides insight of ED as a brine management technology by using a laboratory scale stack to test commercially available membranes. The RO concentrate used was gathered from Kay Bailley Hutchison (KHB) RO facility in El Paso, Texas. While testing different membrane configurations under controlled conditions, the system was monitoring conductivity and current over time. Experimental testing with two different voltages (0.4V and 0.8V) was performed to understand the effect of voltage with high salinity water in ED. The observed diluate conductivity removal percentage ranged from 8.06% to 16.48% while the total specific energy consumption (SEC) ranged from 5.45 to 31.57 kWh/m3. Monovalent selective membrane configurations demonstrated lower SEC, with retention of desalination properties even at low voltage applied. These findings validate the use of ED to treat brine from RO systems, with a potential for larger scale applications.