Reforming Integrated with Oxidation in Micro-Heat Exchanger Reactor with Circular Micro-Channels

Document Type : Research Paper

Authors

Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, Semnan, Iran

Abstract

Steam reforming integrated with oxidation of methanol was considered with numerical simulation. The parallel micro-channels with circular cross sections were used. Because when the catalytic deposited inside the rectangular micro-channels, it fills up the edges. Hence, the approximation of a cylindrical channel is appropriate. Effect of this changing in cross section was considered and results show conversion is lower in circular model. Also, effects of operating conditions such as inlet temperature, feed flow rate, inlet composition (as steam/carbon ratio) and geometry parameters such as the distance between two rows and two columns were considered. The results show that with increasing inlet temperature and steam/carbon ratio, methanol conversion increases while with increasing feed flow rate, methanol conversion decreases. Geometry parameters are another consideration and the results show that with increasing t1 (the distance between oxidation and steam reforming micro-channels) methanol conversion decreases and with increasing t1/t2 ratio (t2 is the distance between two oxidation micro-channels or two steam reforming micro-channels), methanol conversion increases firstly and then keep almost constant.

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