Recovery of Elemental Selenium Nanoparticles (SeNPs) from the Aerobic Batch Reduction of Selenite (Se(IV)) in water by a mixed culture of Enterococci.

The U.S. EPA completed a study and report that analyzed the long-term performance of five facilities in the US and one in Canada that implemented innovative technologies or process enhancements designed to significantly intensify treatment or enhance the removal of nitrogen or phosphorus species. The analysis centered on assessing technology performance and statistical variability of plant effluent nutrient concentrations over a three-year period. Each case study presents a detailed process description, performance analysis, assessment of process train consistency in meeting permit limits, and lessons learned in process implementation. The technologies evaluated include two sidestream deammonification processes, phosphorus stripping, sidestream enhanced biological phosphorus removal, and a submerged nitrification reactor process for consistent ammonia removal from lagoons to low levels, as well as an innovative modification of a BNR process for enhanced total nitrogen removal to low levels. Benefits experienced included reduction of sidestream nitrogen loads, reduction in energy and chemical use, and reduction of total nitrogen, phosphorus, or ammonia to very low effluent concentrations.