Economic analysis of electrodialysis, denitrification, and anammox for nitrogen removal in municipal wastewater treatment

Technologies to remove nitrogen from wastewater are employed to preserve drinking water and prevent environmental damage. Nitrification/denitrification and partial nitrification-anammox are two accepted nitrogen removal techniques for wastewater treatment plants. These processes require energy for aeration and can release fugitive greenhouse gases in the form of nitrous oxide. Electrodialysis could potentially be used as an alternative to remove ammonium from waste streams, but previous experimentation has concluded that concentrate streams experience rapid scaling and fouling of membranes. This analysis compiles literature values to compare the state-of-the-art of municipal nitrogen removal to the new electrodialysis technique on an economic basis. Results show that nitrogen removal and recovery by electrodialysis is estimated to lower both initial capital costs and subsequent operation costs than traditional N removal technologies.