Effects of gas velocity on formation of carbon deposits on AS-SOFC fuel electrodes

Konrad Motylinski, Marek Skrzypkiewicz, Yevgeniy Naumovich, Michał Wierzbicki, Jakub Kupecki

Abstract


The elevated operating temperatures of solid oxide fuel cells (SOFC) create favorable kinetics for the oxidation of carboncontaining
gas mixtures, which may include carbon monoxide and light organic compounds. The presence of carbon-based
components in the fuel might result in the formation and deposition of soot on the surface of the anode in a fuel cell. This
process depends on and is driven by the prevailing thermodynamic, kinetic and electrochemical conditions. The present
study was premised on the following: in addition to the aforementioned parameters providing for the operating conditions,
gas velocity also affects the formation of deposits on the anode. The role of fuel gas velocity in the process was studied
experimentally using 5 cm x 5 cm anode supported solid oxide fuel cells (AS-SOFC) at 750°C at velocities in the range 0.1
to 0.9 m/s. It was found that carbon deposition was clearly observable approximately 24 hours after the necessary conditions
were attained. An intense stage of performance degradation typically lasts for a period of up to 60 hours. An increase in fuel
flow velocity leads to an acceleration in the carbon deposition process. The correlation between velocity and cell degradation
due to this phenomenon was determined and the corresponding function was proposed.


Keywords


Boudouard Reaction, Carbon Deposition, SOFC, Soot Formation

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References


A. Silva, C. Malfatti, I. Iler, Thermodynamic analysis of ethanol steam

reforming using gibbs energy minimization method: A detailed study of

the conditions of carbon deposition, International Journal of Hydrogen

Energy 34 (2009) 4321–4330.

S. Singhal, K. Kendall, High temperature solid oxide fuel cells: fundamentals,

design and applications, 2003.

S. Srinivasan, Fuel cells. From fundamentals to applications, 2006.

C. Song, Fuel processing for low-temperature and high-temperature

fuel cells. challenges, and opportunities for sustainable development

in the 21st century, Catalysis Today 17 (2002) 17–49.

E. S. Inc., Fuel cell handbook (Seventh edition), 2004.

Y. Liu, Performance evaluation of several commercial alloys in a reducing

environment, Journal of Power Sources 179 (1) (2008) 286–291.

J. Macek, B. Novosel, M. Marinsek, Ni-ysz sofc anodes – minimization,

Journal of the European Ceramic Society 27 (2007) 487–491.

F. Cayan, M. Zhi, S. Pakalapati, I. Celik, N. Wu, R. Gemmen, Effects

of coal syngas impurities on anodes of solid oxide fuel cells, Journal of

Power Sources 185 (2008) 595–602.

T. Chen, W. Wang, H. Miao, T. Li, C. Xu, Evaluation of carbon deposition

behavior on the nickel/yttrium-stabilized zirconia anode-supported

fuel cell fueled with simulated syngas, Journal of Power Sources 196

(2011) 2461–2468.

V. Subotic, C. Schluckner, C. Hochenauer, An experimental and numerical

study of performance of large planar esc-sofcs and experimental

investigation of carbon depositions, Journal of the Energy Institute

(2016) 121–137.

Y. Zhang, Z. Yang, M. Wang, Understanding on the carbon deposition

on the nickel/yttrium-stabilized zirconia anode caused by the co containing

fuels, Journal of Power Sources 279 (2015) 759–765.

T. Takeguchi, R. Kikuchi, T. Yano, K. Eguchi, K. Murata, Effect of precious

metal addition to ni–ysz cermet on reforming of ch4 and electrochemical

activity as sofc anode, Catalysis Today 84 (3/4) (2003)

–222.

T. Takeguch, Y. Kani, T. Yano, R. Kikuchi, K. Eguchi, K. Tsujimoto,

Y. Uchida, A. Ueno, K. Omoshiki, M. Aizawa, Study on steam reforming

of ch4 and c2 hydrocarbons and carbon deposition on ni–ysz cermets,

Journal of Power Sources 112 (2) (2005) 588–595.

T. Borowiecki, A. Gotebiowski, B. Stasifiska, Effects of small moo3 additions

on the properties of nickel catalysts for the steam reforming of

hydrocarbons, Applied Catalysis A: General 153 (1997) 141–156.

D. Niakolas, J. Ouweltjes, G. Rietveld, V. Dracopoulos, S. Neophytides,

Au-doped ni/gdc as a new anode for sofcs operating under rich ch4

internal steam reforming, International Journal of Hydrogen Energy

(15) (2010) 7898–7904.

J. Koh, Y. Yoo, J. Park, H. Lim, Carbon deposition and cell performance

of ni-ysz anode support sofc with methane fuel, Solid State Ionics 149

(2002) 157–166.

V. Alzate-Restrepo, J. Hill, Carbon deposition on ni/ysz anodes exposed

to co/h2 feed, Journal of Power Sources 142 (2005) 194–199.

D. Singh, E. Hernandez-Pacheco, P. Hutton, N. Patel, M. Mann, Carbon

deposition in an sofc fueled by tar-laden biomass gas: a thermodynamic

analysis, Journal of Power Sources 142 (2005) 194–199.

K. Girona, J. Laurencin, J. Fouletier, F. Lefebvre-Joud, Carbon deposition

in ch4/co2 operated sofc: Simulation and experimentation studies,

Journal of Power Sources 210 (2012) 381–391.

K. Eguchi, H. Kojo, T. Takeguchi, R. Kikuchi, K. Sasaki, Fuel flexibility

in power generation by solid oxide fuel cells, Solid State Ionics 152-153

(2002) 411–416.

J. Milewski, A mathematical model of sofc: A proposal, Fuel Cells

(5) (2012) 709–721.

J. Kupecki, J. Milewski, J. Jewulski, Investigation of sofc material properties

for plant-level modeling, Central European Journal of Chemistry

(5) (2013) 664–671.

C. Huang, S. Shy, C. Chien, C. Lee, Parametric study of anodic microstructures

to cell performance of planar solid oxide fuel cell using

measured porous transport properties, Journal of Power Sources

(8) (2010) 2260–2265.

J. Kupecki, J. Milewski, A. Szczesniak, R. Bernat, K. Motylinski, Dynamic

numerical analysis of cross-, co-, and counter-current flow configuration

of a 1 kw-class solid oxide fuel cell stack, International Journal

of Hydrogen Energy 40 (45) (2015) 15834–15844.

R. Kluczowski, M. Krauz, M. Kawalec, J. Ouweltjes, Near net shape

manufacturing of planar anode supported solid oxide fuel cells by using

ceramic injection molding and screen printing, Journal of Power

Sources 268 (2014) 752–757.

J. Kupecki, Modeling platform for a micro-chp system with sofc operating

under load changes, Applied Mechanics and Materials 607 (2014)

–208.

K. Badyda, J. Kupecki, J. Milewski, Modelling of integrated gasification

hybrid power systems, Rynek Energii 88 (3) (2010) 74–79.

J. Kupecki, J. Jewulski, K. Badyda, Selection of a fuel processing

method for sofc-based micro-chp system, Rynek Energii 97 (6) (2011)

–162.

Z. Jaworski, B. Zakrzewska, P. Pianko-Oprych, On thermodynamic

equilibrium of carbon deposition from gaseous c-h-o mixtures: Updating

for nanotubes, Reviews in Chemical Engineering 33 (3) (2002)

–235.


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