Studying the applicability of electrodialysis technology to treat groundwater in CKDu regions, Sri Lanka: operational parameter optimization of the pilot project

ABSTRACT The population in the dry regions relies mainly on groundwater for their water needs in Sri Lanka. The use of ED technology for groundwater treatment has been increasing globally, and Sri Lanka is also considering its introduction to treat groundwater in rural areas because of its higher efficiency and easier operation compared to other membrane technologies. A pilot plant was installed in Kahatagasdigiliya, NCP, Sri Lanka focusing on the selective removal of problematic ions identified in the area. Operational parameters were adjusted to remove identified problematic ions during the TED process, and suitable operational parameters were selected considering treated water quality and the water demand of villagers. TED was operated at a selected condition of 12 m3/h flow rate and 45 V voltage. The final effluent water quality meets the Sri Lanka Standard (SLS) 614:2013 limits, with a higher removal efficiency of 65.63% (hardness) and 55.37% (F-). This TED system with a capacity of 260 m3 day has been operational since 2017 in Sri Lanka, providing better quality water to villagers and ensuring water safety in the area. This pilot TED provides guidance on operating ED for selective removal of problematic ions in drinking water in real-world applications.