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 dry regions relies mainly on groundwater for their water needs in Sri Lanka. The use of the ED process for groundwater treatment has increased globally, and Sri Lanka is also considering introducing ED technology to treat groundwater in rural areas due to its relatively high efficiency and ease of 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 parameters are below SLS 614:2013 water quality 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 suggests possible guidance for operating ED to achieve better selective removal of problematic ions in drinking water in real-world applications.