Biogas combustion characterization for flame fuel cell utilization

Anaerobic digesters (AD) utilize microorganisms to breakdown organic materials, such as food waste and waste water sludge; in turn, this process generates a biogas containing methane, carbon dioxide, and trace quantities of other gases. Combustion can reform the methane, resulting in hydrogen, carbon monoxide and heat generation suitable for solid oxide fuel cell (SOFC) use. By varying the combustion equivalence ratio, SOFCs are capable of utilizing fuel-rich combustion byproducts as a fuel source for electrical power generation. The development of a combined SOFC-AD system is of interest due to its ability to generate heat and electricity from a waste stream. A source meter and the four-probe method were used to characterize SOFC electrical performance for various methane to carbon dioxide ratios, as well as various combustion equivalence ratios. The material properties of SOFCs make them suitable for use in these high temperature combustion environments, and their simplicity and flexibility makes them advantageous over other combined heat and power systems.