Model methane steam reforming

One-dimensional models of a solid oxide fuel cell (see Chapter 9) and a methane-steam reformer [19, 20] were incorporated into the ProTRAX programming environment for transient studies. Lumped parameter ProTRAX sub-models were used for the remaining system components (heat exchangers, turbomachinery, valves, etc ). A schematic of the model is provided for reference in Figure 8.21. 

For the steam reforming reaction (10.20) at the anode, some formulae describing the reaction rate have been proposed [11, 12], To model the steam reforming reaction, it is better to measure the reaction rate for the methane reforming reaction using a practical Ni/YSZ cermet. In the present calculations, the following empirical formula is used as the reaction rate ... 

Assaf, E.M., Jesus, C.D.F. and Assaf, J.M. (1998) Mathematical modelling of methane steam reforming in a membrane reactor An isothermic model. Brazilian Journal of Chemical Engineering, 15 (2), 160-166. 

Lee, D.K., Baek, I.H., and Yoon, W.L. Modeling and simulation for the methane steam reforming enhanced by in situ C02 removal utilizing the CaO carbonation for H2 production. Chemical Engineering Science, 2004, 59 (4), 931. 

Cao, C., Wang, Y., and Rozmiarek, R.T. Heterogeneous reactor model for steam reforming of methane in a microchannel reactor with microstructured catalysts. Catalysis Today, 2005,110 (1—2), 92. 

Fig. 2 Comparison of microkinetic model calculation with previously published data for methane steam reforming at 1 MPa. Markers are experimental data from ref. (15), lines are data from the microkinetic model.

Lin Y, Liu S, Chuang C, Chu Y (2003) Effect of incipient removal of hydrogen through palladium membrane on the conversion of methane steam reforming experimental and modeling. Catal Today 82 127-139... 

Patil CS, Annaland MVS, Kuipers JAM (2007) Fluidised bed membrane reactor for ultrapure hydrogen production via methane steam reforming experimental demonstration and model validation. Chem Eng Sci 62 2989-3007... 

De Falco M, Marrelli L, Basile A (2009) An industrial application of membrane reactors modelling of the methane steam reforming reaction, Chapter 9. In Simulation of membrane reactors. Nova Science Publishers Inc., New York, ISBN 978-1-60692-425-9... 

Fernandez F, Soares A Jr (2006) Methane steam reforming modeling in a palladium membrane reactor. Fuel 85 569-573... 

The application of these reactor models is quite straightforward. For example, let us consider again the hydrogen production in a membrane reactor applied for methane steam reforming. Suppose that the membrane used is a dense defect free Pd-based membrane which obeys the Richardson equation (10.9). The reactions taking place in the reactor are ... 

Table 2.4 Overview on mathematical models used for simulating the methane steam reforming (MSR) reaction in packed-hed membrane reactors (PBMRs) and fluidized-hed membrane reactors (FBMRs)... 

Marin, P., Patino, Y., Diez, F. V., Ordonez, S. (2012). Modelling of hydrogen perm-selective membrane reactors for catalytic methane steam reforming. International Journal of Hydrogen Energy, 37, 18433—18445. 

Patel, K. S., Sunol, A. K. (2007). Modeling and simulation of methane steam reforming in a thermally coupled membrane reactor. International Journal of Hydrogen Energy, 32, 2344-2358. 

Simakov, D. S. A., Sheintuch, M. (2011). Model-hased optimization of hydrogen generation by methane steam reforming in autothermal packed-bed membrane reformer. AIChE Journal, 57, 525-541. 

Robbins et al. performed transient modelling of methane steam reforming over a 1.7 wt.% rhodium/y-alumina catalyst combined with hydrogen or methane combustion over a 0.6 wt.% paUadium/y-alumina catalyst in a co-current plate heat-exchanger... 

Marigliano et al. performed further modelling work for methane steam reforming and water-gas shift in membrane reactors [415]. They defined the sweep factor I as the ratio of flow rates of inert gas on the permeate side to the flow rate of methane on the reaction side of the membrane ... 

Vogiatzis et al. modelled heat dispersion effects in future water-gas shift membrane reactors on an industrial scale [418]. A catalyst bed of 2-m length was assumed, which contained tubular membranes with a 4-mm outer diameter. The distance between the tubes, which was filled by the fixed catalyst bed, was only 23 mm and thus the model could be applied for systems of a smaller scale. Heat dispersion effects occurred in the reactor. Overheating of the catalyst bed by about 30 K occurred, which lead to increased conversion compared with an isothermal catalyst bed. However, the opposite effect is to be expected with an endothermic reaction, such as methane steam reforming. 

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