(53a) Aspen Plus Simulation of Steam-Biogas Reforming and Comparison with Experimental Data Obtained over a Metal-Foam-Coated Pd-Rh Catalyst
AIChE Spring Meeting and Global Congress on Process Safety
2015
2015 AIChE Spring Meeting and 11th Global Congress on Process Safety
Emerging Technologies in Clean Energy for the Twenty-First Century
Carbon Capture and Utilization Routes to High Value Products II
Monday, April 27, 2015 - 3:30pm to 4:00pm
The steam biogas reforming (SBR) process was studied using the Aspen Plus process simulation tool. Model biogas (60% CH4 + 40% CO2) mixed with steam at S/C (steam to methane) ratios of 1.25, 1.50 and 1.75 was used as the feedstock. SBR equilibrium data were obtained over a temperature range of 923 to 1123 K at 1 atm pressure through Gibbs free energy minimization. The equilibrium data were compared with experimental data obtained over a [Pd(7)-Rh(1)/(CeZrO2•Al2O3)]/metal foam catalyst at a GHSV of 20,000 h-1. At 923 K, CH4 conversion over the catalyst was approximately 15% lower than the equilibrium conversion, but the difference was attenuated with increasing temperature and was completely removed around 1123 K. The CO/(CH4 + CO2) yields over the catalyst were lower than the equilibrium data in the entire temperature range due to the lower CH4 as well as CO2 conversions. The H2/CH4 yields over the catalyst were lower initially, but exceeded the equilibrium data at the temperature around 1050 K due to water gas shift (WGS) reaction being favored over the catalyst. The WGS reaction was responsible for the lower CO2 conversion. The process thermal efficiencies were calculated through the simulation and experimental data and the results were comparable. The comparisons of the experimental data with the Aspen Plus simulation results will help to enable the SBR process optimization with a focus on improving the net thermal efficiency and product syngas yield.
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