Wyniki wyszukiwania - BazTech

1

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

Motylinski K., Skrzypkiewicz M., Naumovich Y., Wierzbicki M., Kupecki J.

Journal of Power Technologies

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2018

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Vol. 98, nr 4

322--328

EN

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.

2

Model Approach of Carbon Deposition Phenomenon in Steam and Dry Methane Reforming Process

Kaczmarczyk R., Gurgul S.

Archives of Metallurgy and Materials

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2014

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Vol. 59, iss. 1

145--148

EN

This paper presents thermodynamic conditions for carbon deposition in steam and dry methane reforming process. Ranges of substrate concentrations and temperatures for creating carbon deposition were specified in an analytical form. In the description of the conversion of methane CH4-H2O and CH4-CO2 parametric equations were used, which allowed to define equilibrium composition of the process. The article formulates the basic assumptions of parametric equations models and their use to describe the course of the homogeneous reactions. The results may provide a model basis for the description of properties of the mixed reforming process CH4-H2O-CO2.

PL

W prezentowanej pracy przedstawiono termodynamiczny warunek wytracania wegla w procesie parowego i suchego reformingu metanu. Określono zakresy stężenia substratów i temperatury tworzenia depozytów węglowych w postaci analitycznej. Opis konwersji metanu CH4-H2O i CH4-CO2 zrealizowano z wykorzystaniem formalizmu równań parametrycznych, pozwalającego na określenie składu równowagowego zachodzącego procesu. Przedstawiono podstawowe założenia modelu równań parametrycznych oraz ich wykorzystanie do opisu przebiegu reakcji homogenicznych. Uzyskane wyniki mogą stanowić bazę modelowa do opisu własności procesu reformingu mieszanego CH4-H2O-CO2.

3

Model Approach of Carbon Deposition Phenomenon in Mixed H2O/Co2 Methane Reforming Process

Kaczmarczyk R., Gurgul S.

Archives of Metallurgy and Materials

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2014

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Vol. 59, iss. 4

1379--1383

EN

This paper presents thermodynamic conditions for carbon deposition in methane reforming process by gas phase H2O/CO2. Ranges of substrate concentrations and temperatures for creating carbon deposition were specified in an analytical form. In the description of the conversion of methane CH4-(H2O/CO2) parametric equations were used, which allowed to define equilibrium composition of the process. The article formulates the basic assumptions of parametric equations models and their use to describe the course of the homogeneous reactions. The results may provide a model basis for the description of properties of the mixed reforming process CH4 - (H2O/CO2).

PL

W prezentowanej pracy przedstawiono termodynamiczny warunek wytrącania węgla w procesie reformingu metanu faza gazowa H2O/CO2). Określono zakresy stężenia substratów i temperatury tworzenia depozytów węglowych w postaci analitycznej. Opis konwersji metanu CH4-(H2O/CO2) zrealizowano z wykorzystaniem formalizmu równań parametrycznych, pozwalającego na określenie składu równowagowego zachodzacego procesu. Przedstawiono podstawowe założenia modelu równań parametrycznych oraz ich wykorzystanie do opisu przebiegu reakcji homogenicznych. Uzyskane wyniki mogą stanowić bazę modelowa do opisu własności tzw. procesu reformingu mieszanego CH4-(H2O/CO2).