SUSTAINABLE ENERGY MANAGEMENT: AUGMENTING ANAEROBIC DIGESTERS TO INCREASE BIOGAS-FUELED COMBINED HEAT AND POWER PRODUCTION

This paper focuses on technologies that augment anaerobic digestion to increase biogas fueled combined heat and power generation. In recent years, there has been heightened awareness of the need to develop sustainable sources of energy in order to supplant nonrenewable sources of energy, primarily fossil-fuel-based energy. There is a worldwide concern about the impact of fossil fuels on the climate due to global warming. This compounded with increasing power and natural-gas utility costs make the case for increasing self-generated energy more compelling. In fact, some utilities have achieved energy independence through a combination of decreasing energy demand and increasing energy output. Visionaries, including the authors of this paper, are calling for the wastewater industry to adopt the goal of energy independence.Ultimately, energy independence would be achieved by (1) energy conservation, most importantly, (2) creating more efficient systems, and (3) renewable energy provided by a combination of sources, such as solar power, wind power, hydropower, geothermal power, and bioenergy. Hence, a movement toward maximizing utilization of biologically derived energy has recently become of more interest to wastewater utility management as part of the global renewable energy portfolio. Also, one of the principles of sustainability is to make use of existing infrastructure; hence, as a common part of current wastewater infrastructure, conventional anaerobic biological systems have been targeted for their ability to produce sustainable sources of bioenergy.In addition to a discussion of technologies to convert biogas to combined heat and power, this paper discusses three approaches to augmenting biogas production from anaerobic digestion which include:Anaerobic Digestion Pre-treatment TechnologiesAdvanced Anaerobic Treatment TechnologiesCo-digestion of Supplemental Wastes