标题：Effect of hydrogen addition on the catalytic combustion of fuel-lean carbon monoxide-air mixtures over platinum for micro-scale power generation applications
期刊名称：Bulletin of the Institute of Heat Engineering
印刷版ISSN：2083-4187
出版年度：2018
卷号：98
期号：1
页码：161-169
语种：English
出版社：Warsaw University of Technology
摘要：The catalytic combustion of hydrogen and carbon monoxide over Pt/ -Al2O3 catalyst was investigated numerically for H2/CO/O2/N2 mixtures with overall lean equivalence ratios ' = 0.117 .. 0.167, H2:CO molar ratios 1:1.5 .. 1:6, a pressure of 0.6 MPa, and a surface temperature range from 600 to 770 K relevant for micro-scale turbines and large gas turbine based power generation systems. Simulations were carried out with a two-dimensional CFD (Computational Fluid Dynamics) model in conjunction with detailed hetero-/homogeneous kinetic schemes and transports to explore the impact of hydrogen addition on catalytic combustion of carbon monoxide. The detailed reaction mechanisms were constructed by implementing recent updates to existing kinetic models. The simulation results indicated that the hydrogen addition kinetically promotes the catalytic combustion of carbon monoxide at wall temperatures as low as 600 K, whereby the catalytic reactions of hydrogen are fully lit-off and the conversion of carbon monoxide is mixed transport/kinetically controlled. Such a low temperature limit is of great interest to idling and part-load operation in large gas turbines and to normal operation for recuperative micro-scale turbine systems. Kinetic analysis demonstrated that the promoting impact of hydrogen addition on catalytic combustion of carbon monoxide is attributed to the indirect effect of hydrogen reactions on the surface species coverage, while direct coupling steps between hydrogen and carbon monoxide are of relatively minor importance. The added hydrogen inhibits the catalytic oxidation of carbon monoxide for wall temperatures below 520 K, which are well below the minimum inlet temperatures of reactants in micro-scale turbine based power generation systems.
关键词：Catalytic combustion;Hydrogen promotion;Carbon monoxide;Synthesis gas;Power generation system
