Direct carbon fuel cells

Not all of the gas is wasted. About 300 MW of electricity is generated from landfills. A variety of electric generation systems have been employed by a small number of developers. Most projects use simple technology and are small (2—10 MW). However, an EPRI study has estimated that landfill gas resources in the United States could support 6,000 MW of generation if utilized in 2-MW-sized carbonate fuel cells. Constmction on the world s first utihty-scale direct carbonate fuel cell demonstration was begun in California. If successful, EPRI estimates that precommercial 3-MW plants based on this design could become available by the end of this decade at an installed cost of 17,000/kW. 

Comprehensive discussions of fuel cells and Camot engines Nemst law analytical fuel cell modeling reversible losses and Nemst loss and irreversible losses, multistage oxidation, and equipartition of driving forces. Includes new developments and applications of fuel cells in trigeneration systems coal/biomass fuel cell systems indirect carbon fuel cells and direct carbon fuel cells. 

H. Maru et al., "ERC Direct Carbonate Fuel Cell Program Overview," DOE Contractor s Review Meeting, Morgantown, WV, August 26-28, 1997. 

J. Ding et al., A Computer Model for Direct Carbonate Fuel Cells, Proceedings of the Fourth International Symposium on Carbonate Fuel Cells, 19C Electrochemical Society Meeting, Montreal, May 1997. 

Could a direct carbon fuel cell work without employing, as the MCFC, melting temperatures ... 

A new version of MCFC technology - the direct carbon fuel cell (DCFC) - is under development at the Lawrence Livermore National Laboratory in the USA. Instead of using gaseous fuel, a slurry of finely divided carbon particles dispersed in molten alkali metal carbonates is fed to the cell. The carbon is made by the pyrolysis of almost any waste hydrocarbon e.g., petroleum coke), a process that is already carried out industrially on a large scale to produce carbon black for use in the manufacture of tyres, inks, plastic fillers, etc. The pyrolysis reaction yields hydrogen that can itself be utilized in another fuel cell ... 

In the development of direct carbon fuel cells, different directions were followed with respect to the electrolytes—high-temperature melts of carbonates or sodium hydroxide and high-temperature solid electrolytes. 

A difficulty of principle arises when using a solid electrolyte in direct carbon fuel cells. In fact, in fuel cells with a liquid electrolyte (solution or melt) the entire surface area of the carbon material is in contact with the electrolyte (is wetted by the electrolyte). In fuel cells with a solid electrolyte, to the contrary, the contact between the solid carbon material and the solid electrolyte is a mere point contact, and the working surface area is much smaller. 

The direct carbonate fuel cell is a variant of molten carbonate fuel cells (MCFC) in that it internally reforms methane-containing fuels within the anode compartment of the fuel cell (Matsumoto et al., 1990 Farooque, 1991 Sasaki et al., 1993 Shinoki et al., 1995). The largest demonstration of MCFC technology has been California s 2-MW Santa Clara Demonstration Project (Fuel Cell Engineering Corporation, 1997). 

Ding J., Patel P.S., Farooque M., Maru H.C., 1997. A computer model for direct carbonate fuel cells. In Proceedings of the Fourth International Symposium on Carbonate Fuel Cell Technology, Montreal, Quebec. 

Hemmes, K., Houwing, M., and Woudstra, N. (2010) Modeling of a methane fuelled direct carbon fuel cell system./. Fuel Cell Sci. Technol, 7 (6), 061008 / 1-061008/6. 

Giddey S, Badwal SPS, Kulkami A, Mannings C (2012) A comprehensive review of direct carbon fuel cell technology. Prog Energ Combust 38 360-399. doi 10.1016/j.pecs.2012.01.003... 

Direct Carbon Fuel Cells (DCFC). In direct carbon fuel cells, solid carbon (presumably a fuel derived from coal, pet-coke or biomass) is used directly in the anode, without an intermediate gasification step. Concepts with solid oxide, molten carbonate, and alkaline electrolytes are all under development. The thermodynamics of the reactions in a DCFC allow very high efficiency conversion. Therefore, if the technology can be developed into practical systems, it could ultimately have a significant impact on coal-based power generation. 

S. Katikaneni, C. Yuh and M. Farooque, The Direct Carbonate Fuel Cell Technology Advances in Fuel Processing and Internal Reforming, ACS Fuel Chemistry, 46(2) 685-688, Preprints, 2001. 

Cao D., Y. Sun, G. Wang, Direct carbon fuel cells Fundamentals and recent developments, J. Power Sources, 167, 250 (2007). 

Desclaux P, Numberger S, Stimming U (2010) Direct carbon fuel cells. In Steinberge-Wilckens R, Lehnert W (eds) Innovations in fuel cell technologies. The Royal Society of Chemistry, Cambridge, p 190-211 doi 10.1039/9781849732109-00190... 

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