Review and Outlook on the Utilization of Low-Concentration Coalbed Methane for Power Generation by Solid Oxide Fuel Cells

Abstract

With the growing global demand for clean energy, more and more attention has been given to the energy conversion efficiency of low-quality fuels. A solid oxide fuel cell (SOFC) is expected to be one of the ideal technologies for clean and efficient utilization of low-concentration coalbed methane (CBM) because it can achieve efficient utilization of low-quality fuels. This review examines the challenges of SOFC technology fueled by low-concentration CBM. In comparison to fuels such as hydrogen and natural gas, lowconcentration CBM usually contains a large number of other gas components in addition to methane, which reduces the chemical reactivity of CBM and leads to a decrease in the utilization efficiency. The effects of different carbon-containing fuels on the cell performance of SOFC have been investigated by a great deal of research, and the results reveal that methane tends to be the main source of carbon deposition, whereas oxygen-containing fuels can have a positive effect on carbon deposition. In the current SOFC technology fueled by hydrocarbon fuels, concentration polarization is also a major factor contributing to the lack of durability and stability of the cell, with the exception of carbon deposition and sulfur poisoning. In addition, the temperature and other operating environments also have different degrees of influence on the cell performance in the SOFC technology fueled by low-concentration CBM. Therefore, the development of cell materials and the optimization of the system structure of a low-concentration CBM-fueled SOFC are still key research directions for the future.

In Situ Exsolved CoFe Alloy Nanoparticles on Gd2SrCo0.8Fe1.2O7−δ for Direct Hydrocarbon Fuel Solid Oxide Fuel Cells

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Utilization of Thermocatalysts in Solid Oxide Fuel Cells (SOFCs) Fed with Hydrogen-Rich Fuels: A Mini-Review

“…Solid oxide fuel cells (SOFCs) are recognized as one of the most efficient energy conversion devices, which directly convert the chemical energy stored in fuels into electrical energy without the limitation of the Carnot cycle at 600–1000 °C. − In addition to hydrogen, various fuels such as hydrocarbons, hydronitrogens, and biomass are also fed to SOFCs. − The hydrocarbons (compounds of carbon and hydrogen) come from abundant fossil fuels on the earth, and biomass (compounds of carbon, hydrogen, and oxygen) is a kind of renewable source derived from carbonaceous waste materials. − The biogas and liquid biomass (e.g., methanol and ethanol) can be operated directly as fuels, and the solid biomass can be converted into gaseous fuels via high-temperature pyrolysis to be used in SOFCs . The biogas composition depends on the type of raw biomass and production processes.…”