Brackish Water Desalination Using Electrodialysis: Influence of Operating Parameters on Energy Consumption and...

Groundwater is one of the main water sources for consumption, domestic use, agriculture, and tourism in coastal communities. However, high total dissolved solids (TDS) levels in the water (700-2000 mg L^-1 TDS) and electrical conductivity (3000-5000 µS cm^-1) threaten the health and economic growth opportunities for residents. This research aims to evaluate the performance of a laboratory-scale electrodialysis system as a technology for desalinating brackish water. For this purpose, water samples were collected from real groundwater sources. Batch experiments were conducted with varying operational parameters, such as voltage (2-10 V), feed volume (100-1600 mL), recovery rate (50-80%), and cros-flow velocity (1.3-5.1 cm s^-1) to determine the electrodialysis system setup that meets the requirements for drinking water in terms of TDS and energy efficiency. A total specific energy consumption of 1.65 kWh m^-3, including pumping energy, was achieved at a laboratory scale. The conditions were as follows: flow velocity of 5.14 cm s^-1, applied voltage of 6 V, feed volume of 1.6 L, and a water recovery of 66%. Furthermore, increasing the flow velocity and the applied voltage enhanced the desalination kinetics and salt removal. Additionally, the system presented opportunities for scalability. This research aims to evaluate a sustainable membrane-based treatment technology for meeting the growing demand for water resources in coastal communities, particularly in developing countries in South America.