The objective of this project is to design and model a self-sufficient, energy-independent resource recovery facility (RRF) capable of converting the chemical energy in wastewater, sludge, food scraps, and fats, oils and grease (FOG) produced on military installations into heat and electrical energy using anaerobic bioreactor technology. Because of the relative novelty of RRFs as innovative energy solutions on military installations, this project’s objectives focus on identifying the appropriate use for produced biogas to maximize thermal and electrical energy production, barriers to implementation, and transfer of design and lessons learned to other installations for possible RRF implementation. 

Anaerobic bioreactors are special tanks that use tiny organisms (microbes) that don't need oxygen to break down waste, turning it into biogas, which is mostly methane (a gas that can be burned for energy). These bioreactors have recently been proposed to replace the usual way wastewater is cleaned aerobically, (called "activated sludge") because activated sludge is highly resource intensive. The Staged Anaerobic Fluidized-bed Membrane Bioreactor (SAF-MBR) is the most advanced anaerobic bioreactor technology and can be the centerpiece of a re-envisioned wastewater treatment movement. The SAF-MBR was the subject of a previous ESTCP project (ER-201434; 2019 Project of the Year Award for Environmental Restoration). Generally, the SAF-MBR is a two-stage membrane bioreactor designed to treat domestic wastewater to effluent discharge standards, while maximizing biogas production. In addition to the SAF-MBR, wastewater sludge can be combined with food scrap wastes and FOG in another anaerobic bioreactor – an anaerobic co-digester. Anaerobic co-digestion is the subject of study at the U.S. Military Academy (ESTCP project EW22-7278) where the first full-scale codigester in Department of Defense (DoD) is under construction. Anaerobic co-digestion optimizes growth conditions for anaerobic microorganisms to produce additional biogas. Biogas typically contains 65% methane, which can be converted to heat and electrical energy through combined heat and power technologies. To determine the best design, this project will leverage mechanistic and data-driven modeling approaches, technoeconomic analyses, and lifecycle analyses. This project also intends to study technology transfer, to include installation-level opportunities and barriers to full implementation, and the interaction of installations, local municipalities, and privatized wastewater companies. 

The RRF promises to be net energy producing, i.e., it will produce more energy than is required to run the facility, thereby creating an innovative self-sustaining solution that simultaneously cleans water to effluent discharge standards. A principal DoD benefit of RRFs is that they maximize use of organic wastes already generated on military installations, allowing a base to be more self-sufficient by reducing reliance on sources beyond the fence line through installation-level resource management. Results from this study will help installation leadership determine how RRFs best operate on the ground and how they can be used to advance energy security and energy resilience within the DoD. (Anticipated Project Completion - 2028)