Thermodynamic Analysis of Steam Methane Reforming for Hydrogen Production

Thermodynamic equilibrium of steam methane reforming (SMR) reactions in a compact plate heat exchange reformer consisting of plate-type metal-monolithic anodic alumina supported catalyst was studied by Gibbs free minimization using AspenPlus (TM), as a function of pressure (0.1-2MPa), reforming temperature (300-1100 degrees C), steam to carbon ratio (S/C=0.5-6). The formation of C (s), operating conditions and system efficiency were investigated as well. The results show that there is no C(s) formed when the steam to carbon ratio is higher than 1.4 at pressure of 0.1MPa. As both the H-2 yield and system efficiency are concerned, the optimal operating condition is S/C=3 similar to 4 at 700 similar to 750 degrees C and 0.1MPa. CH4 conversion of 98.69%, H-2 yield of 3.49mol.mol(-1) CH4 and system efficiency of 72.73% can be obtained under that condition of S/C=4 at 700 degrees C and 0.1MPa. It is feasible for the reformer being operated at atmospheric pressure. The calculation result fits well with the experimental data from related paper. The heat of the product should be recovered to improve the system efficiency.