Process schemes for future energy-positive water resource recovery facilities.

Abstract

There are numerous successful studies on optimizing the performance of conventional activated sludge (CAS)-based wastewater treatment plants. However, recent studies have shown that a more significant improvement of the plant performance is achievable through integration of established technologies in novel process schemes. High-rate activated sludge system, chemically enhanced primary treatment, partial nitritation-anammox, partial nitrification-denitrification over nitrite and anaerobic digestion are integrated in two process schemes to determine to which extent energy savings and energy production can be achieved with these new process layouts compared to a CAS-based process scheme. The results presented in this paper show that there is potential for achieving future energy-positive water resource recovery facilities through novel integration of mature technologies for municipal wastewater treatment.