| Developments in understanding of copper toxicity on anadromous stream biota have caused stricter regulation of discharged pollutants from municipal wastewater treatment plants across Alaska. Wastewater treatment plants have pursued facility upgrades in order to meet stricter permitting, but capabilities of advanced wastewater treatment processes in cold regions are not well understood, particularly with respect to treatment for copper. The goal of this research was to determine the ability of a bench-scale membrane bioreactor and ultraviolet disinfection to treat copper before discharge into receiving conditions applicable to cold regions. Copper removal by a membrane bioreactor was found to exceed removal by activated sludge by 9%, removal in previously published studies by 6%, and was not affected by cold aeration basin temperatures. Enhanced copper removal correlated with total suspended solids. Ultraviolet disinfection was found to decrease the ultraviolet absorbance and alter the copper complexation capacity of dissolved organic matter. |
