Desalination and fate of nutrient transport in domestic wastewater using electrodialysis membrane process

Abstract

The use of domestic wastewater (DWW) in irrigation offers numerous advantages because of its nutrient compositions. However, the direct use of DWW is risky to both human health and the environment. Hence to comply with circular economy principles, designing a strategy for treating and capturing nutrients from DWW is imperative. Electrodialysis (ED) is a promising technology to achieve this objective. This study investigated the effect of pH and potential difference (voltage) on the performance of the ED. The desalination and transport fate of some nutrients on real DWW is also monitored. The ED system attained an optimum desalination performance of 0.469 mS/cm in 20 min at voltage 15 V and pH 7. Under these conditions, the system achieved 90% nitrate and nitrite removal, while phosphate removal was at 67%. Under continuous flow conditions, the system managed to concentrate the target nutrients in a subsequent chamber. The removal of some organics was also attained.