Wastewater is a resource that contains about 10 times the amount of energy required to treat it (largely as thermal energy). This Focus Group is actively exploring technologies that recover this available energy with the goal of moving them from the emerging or experimental stage into practice.
Energy recovery from sludge is one of the most developed opportunities for treatment plants to engage in energy production practices. Expansions on the two established pathways for energy recovery, anaerobic digestion, and thermal conversion, are being examined at facilities across the nation. New and evolving technologies, including pyrolysis, supercritical water oxidation, hydrothermal liquefaction, and gasification, may hold the key to turning issues such as disposal costs and public opposition to land application into a renewable source of energy and revenue.
Enhancements to AD practice being explored by the Focus Group include pre-digestion technologies, improved mixing and operational control, co-digestion of high strength organic wastes, and advances in biogas conditioning for energy recovery. Digestion enhancements can provide benefits such as increased biogas production, reduced solids generation, increased digester capacity, reduced odors, and more.
The group is funding demonstrations with leveraged support from EPA and DOE. The group is also working cooperatively with organizations such as the Bay Area Biosolids to Energy Coalition (BAB2E). This group is made up of members of the old Biosolids-to-Energy, Digestion Enhancements, and Wastewater to Energy Focus Groups.
Chair: Don Gray, Senior Civil Engineer, East Bay Municipal Utility District (EBMUD)
Vice-Chair: Bob Bucher, Technology Assessment - Engineer IV, King County