Energy and Resource Recovery from Wastewater Treatment: State of the Art and Potential Application for the Army and the DoD

This report summarizes a study to assess energy and resource recovery from wastewater treatment and assess short- and long-term opportunities and impacts for the Army and the Department of Defense DoD in general. The organic material in wastewater contains inherent energy. The challenge is concentrating and recovering this energy. Several methods are available of these, anaerobic digestion either of the sludge, or directly applied to the wastewater using Upflow Anaerobic Sludge Blanket or a similar reactor is the most advanced and can be readily applied to existing military installations or to contingency operations. Recovery of chemical products is another option for wastewater treatment. The most commonly recovered products are nutrients, in the form on nitrogen N and phosphorus P. The simplest way is to recycle the collected and digested biosolids sludges, either for direct soil application or by incorporation into compost. Resource recovery from wastewater may eventually include biopolymers that could make bioplastics or valuable nanometals that are increasingly found in consumer products. Many of the energy recovery technologies and most of the resource recovery approaches beyond simple biosolids recovery require large-scale operations to be economically viable at this time. Wastewater treatment facilities that serve Army and other DoD installations tend to be relatively small, limiting the application of many approaches that might be viable in the civilian sector. ERDC should focus research on technologies that could be economically applied to smaller treatment plants on the order of 3 to 10 mgd.