Re-Orienting Municipal Wastewater Management Systems for Energy Reduction and Energy Production

To achieve the water quality goals of the future while avoiding major increases in the cost and carbon footprint of wastewater management, it will be necessary to develop integrated wastewater systems that are able to recover and utilize the energy contained in municipal wastewater. An alternative model for wastewater management systems focused on maximum recovery of chemical energy in the treatment process is presented in this paper. Two complementary strategies for maximizing the net recovery of chemical energy are discussed: (1) aggressive treatment at the front end of the process such that cost-effective benefits in downstream unit processes are realized and (2) collection of solids in their highest energy density condition and thermally converting these solids to achieve maximum energy production potential and highest value residual solids.