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With the high purity hydrogen source distributed increasing demand, the development of small-scale hydrogen production reactor, the bed was increasingly palladium membrane hydrogen attention, of hydrogen selective and permeable membrane separation process The coupling reaction process, the membrane reactor methane steam reforming die more and more people's attention, but in the past that the model is no real separation process and the hydrogen reforming reaction process coupled together, and no air is introduced consider the formation of NH3. Based on Gibbs free energy minimization principle and Siverts'Law hydrogen separation formulas created using MATLAB and EXCEL membrane reactor steam reforming of methane in the entire mixed model (CSTR model), the model is capable of hydrogen and hydrogen production process The coupling of the separation process and in-depth study of the reaction of carbon and operating conditions on the impact of NH3. Ye is the model with plug flow (PFR) model (Internaltional Journal of Hydrogen Energy, 2009, 34: 4755-4762.) Were compared. Simulation results show that the membrane permeability is less than or greater than 15Km 100Km Time, CSTR and PFR model can be a good model of the actual reaction of the reaction yield of methane and hydrogen, when the membrane permeability 15Km to 100Km in between, PRF model prediction The methane conversion rate and the yield of hydrogen is greater than the predicted value corresponding to the CSTR. In order to verify the accuracy of the model, the model and Adris (Chem.Eng.Sci, 1994, 49: 5833-5843), Roy (Chemical Engineering Science, 1999, 54: 2095-2102.) And Mahecha-Botero (ChemicalEngineering Science , 2008, 64: 2752-2762) published experimental data were compared to the results found in the literature calculated results are in good agreement with the data. Verify the feasibility of the model based on it, using the model of temperature, pressure, film thickness, membrane area, steam to carbon ratio and the oxygen to carbon ratio, membrane measuring the pressure, purge gas such as methane conversion, hydrogen yield, plot carbon and NOX generation and NHX of. Studies show that: the hydrogen through the palladium membrane to break the original thermodynamic equilibrium, reducing the amount of NH3, to promote the reaction to the direction of the generation of hydrogen; or to counteract the adverse effects on the reaction pressure and so on. However, the addition of palladium increases the carbon film formation, reducing the operating temperature of the reactor, pressure in the reactor increased, SC, OC can effectively reduce the generation of carbon. Build a fluidized bed membrane reactor methane steam reforming reaction experiment platform. It was found that the conversion of methane and hydrogen yield increases as the temperature rises, as the operating pressure increases, the methane conversion rate is reduced, the hydrogen production rate increased. When the steam to carbon ratio increased, the methane conversion rate increases, the hydrogen production first increased and then decreased. Experimental results and simulation results more consistent CSTR.
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