Studies of the effects of the reformer in an internal-reforming molten carbonate fuel cell by mathematical modeling

Park, Hong Kyu; Lee, Ye Ro; Kim, Mi‐Hyun; Chung, Gui Yung; Nam, Suk Woo; Hong, Seong Ahn; Lim, Tae Hoon; Lim, Hee Chun

doi:10.1016/s0378-7753(01)00912-0

Cited by 50 publications

(12 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Steady state results for the base case and for all the steady state conditions investigated are summarized in Table 3a and b. The velocities reported in Table 3 refer to single cell velocities required to reach the desired hydrogen utilization, their numerical value is consistent with literature values of around 1 mol h ±1 [7,12,13]. Output temperatures and mean electrolyte temperatures are rather high and close to the highest acceptable values.…”

Section: Steady State Simulation Of the Mcfcsupporting

confidence: 66%

Process Simulation for Molten Carbonate Fuel Cells

et al. 2005

View full text Add to dashboard Cite

In the framework of electricity production from molten carbonate fuel cells (MCFC), this work presents the results obtained from steady state process simulation, coupled with a detailed dynamic model for the cell. The derivation of the model is briefly outlined, and detailed results of the simulation are reported. Macroscopic state variables of the overall system process are investigated by means of sensitivity analysis, yielding clear directions for process improvement and optimisation. The detailed steady state and dynamic simulation of the MCFC for a bi‐dimensional cross flow configuration showed the importance of the state variable distribution in the cell. Both models were based on data from real plants, and the simulation conditions were selected according to real operating conditions. The process studied was a 500 kW MCFC power system based on Ansaldo fuel cell (AFC) technology. The steady state simulation revealed the main interactions among the different devices involved in the process, and the subsequent sensitivity analysis showed that there is room for improvement in electrical efficiency by increasing: i) the steam to methane ratio, ii) the pressure, and iii) the air feed ratio. The dynamic simulation yielded the quantitative response of the system to several, different, perturbations and proved to be a valid tool for determining temperature, current, and voltage profiles as a function of time, within the fuel cells.

show abstract

Section: Steady State Simulation Of the Mcfcsupporting

confidence: 66%

Process Simulation for Molten Carbonate Fuel Cells

et al. 2005

View full text Add to dashboard Cite

show abstract

“…In the industrial sized fuel cells, the difference in the temperature distributions can be up to hundreds of degrees at the surface causing several disadvantages and difficulties. For the DIR-MCFC, with both advantages and disadvantages, many modellings (Wolf and Wilemski, 1983;Standaert et al, 1996;He, 1998;Yoshiba et al, 1998;Bosio et al, 1999;Park et al, 2002;Heidebrecht and Sundmacher, 2003;Wee and Lee, 2005) have been presented for decades. However, some of them have not quantitatively and directly described the results in relation to the three reactions at each point within the cell and others have not presented the experimental data for their modelling.…”

Section: Introductionmentioning

confidence: 99%

Simulation of the performance for the direct internal reforming molten carbonate fuel cell. Part I: distributions of temperature, energy transfer and current density

Wee

Lee

2006

Int. J. Energy Res.

View full text Add to dashboard Cite

SUMMARYThis study examined the temperature distributions of the anode and cathode gases of the cell body as well as the current density distributions at each point of the direct internal reforming molten carbonate fuel cell (DIR-MCFC) using numerical modelling. The model was based on assumptions and experimental data from a 5 cm Â 5 cm sized unit cell operation. The results showed there was an approximately 138C temperature difference between the initial point (0, 0) and end point (1, 1) of the cell body and the temperature increased steadily along with the direction of the anode gas flow. The temperature distribution of the anode gases showed a similar trend to those of the cell body. The temperature of the anode gases was an average 118C lower than that of the cell body. The temperature distributions of cathode gases were relatively higher than those of the anode gases and the cell body. The temperature distributions at each point of the cell body, including the anode and cathode gases, could be explained by the different rates of the electrochemical, methane steam reforming and water-gas shift reactions at each point in the cell body. The current density distribution at the entrance of the cell was the highest at 290 mA cm À2, and decreased steadily to 150 mA cm À2 at the exit. These results were also confirmed by the amount of hydrogen reacted in the electrochemical reaction (referred to Part II). Finally, modelling simulations showed a non-uniform distribution of the temperature and current density throughout the DIR-MCFC were observed. In addition, it was confirmed that the distributions of the reaction rates and gas compositions at each point of the cell also showed a great deal of difference throughout the DIR-MCFC. The non-uniformity of these temperature distributions can lead to deterioration in the cell performance. These might provide the necessary information for solving these problems.

show abstract

“…However, this would not be enough to completely offset the excess heat produced by the electrochemical reaction, resulting in management of the temperature within the cell to be an issue (Freni and Maggio, 1997;Dicks, 1998;Yoshiba et al, 1998;Bosio et al, 1999;Koh et al, 2000;Park et al, 2002;Wee and Lee, 2005).…”

Section: Introductionmentioning

confidence: 99%

Simulation of the performance for the direct internal reforming molten carbonate fuel cell. Part II: comparative distributions of reaction rates and gas compositions

Wee

Lee

2006

Int. J. Energy Res.

View full text Add to dashboard Cite

SUMMARYThis study examined the distributions of the three reaction rates and the compositions of the gases at each point of the unit cell in DIR-MCFC using a numerical simulation. The electrochemical reaction rates at the anode gas entering position were almost two times faster than those at the anode gas outlet position and most of the feeding CH 4 reacted in the region from the position x ¼ 0 to the position x ¼ 0:3: In addition, the water-gas shift reaction became faster from near the half position of the unit cell to the gas outlet position. Therefore, in the rear position of the unit cell, the steam reforming reaction played an important role as a supplementary reaction for providing the H 2 needed in the electrochemical reaction. The rates of the two catalytic reactions in the case without the electrochemical reaction were relatively slower than those in the DIR-MCFC. Unlike the distributions of temperature, the current density, gas compositions and the reactions rates at each point of the DIR-MCFC cell, the exit gas compositions from the simulation in particular could be comparative to those of the experimental results. Although there was an approximately 10% difference between both of them, the extent of the difference was considered to be reasonable for this simulation considering the experimental values that could be included in this simulation such as the lower conversion of the reactions, the lower current density and any other values.

show abstract

Studies of the effects of the reformer in an internal-reforming molten carbonate fuel cell by mathematical modeling

Cited by 50 publications

References 3 publications

Process Simulation for Molten Carbonate Fuel Cells

Process Simulation for Molten Carbonate Fuel Cells

Simulation of the performance for the direct internal reforming molten carbonate fuel cell. Part I: distributions of temperature, energy transfer and current density

Simulation of the performance for the direct internal reforming molten carbonate fuel cell. Part II: comparative distributions of reaction rates and gas compositions

Contact Info

Product

Resources

About