Executive Summary : | The mission of wastewater treatment has transformed from simple contaminant removal to a more sustainable task with the goals to consume less energy and recover more water. In India, groundwater is the primary source of drinking water for 44% of the population, including 99% of the rural population. However, the majority of available groundwater is classified as hard water due to the presence of positively charged multivalent ions (mostly calcium (Ca2+) and magnesium (Mg2+)) in amounts greater than 260 mg/L as CaCO3. Additionally, the quality of the groundwater depletes due to the discharge of fluoride ions either by geological conditions or from anthropogenic sources such as semiconductor, metal processing, fertilizers, and glass-manufacturing industries. Long-term drinking of high fluoride content water can result in mottling of teeth, softening of bones, and ossification of tendons and ligaments. The traditional ground water softening and defluoridation techniques like reverse osmosis, electrochemical coagulation, and ion exchange are energy intensive and generate large amounts of concentrates. Alternatively, the national status for sewage generation is more than their treatment capacity, and therefore, integrating wastewater treatment to groundwater remediation is a novel approach for sustainable waste management. In this study, we adopted a sustainable approach of "utilizing wastewater to achieve groundwater remediation (softening and defluoridation) through their synergy" by employing microbial desalination cell (MDC), an emerging concept that uses bioelectric potential via microbial metabolism to accomplish desalination. The technology is envisioned to be scaled up as technically appropriate, socially acceptable, and economically viable high quality water recovery process. |