(304e) Process Intensification for Hydrogen Generation Using Micro-Channel Steam Reforming

A Tube in Tube micro-Channel Steam Reformer (TTmCSR) was tested on methane showing the capability to intensify the process by an order of magnitude. The mchannel surface bed’s thin catalyst layer directly contacting the reactor wall showed heat transfer of 840 Watt per cc of reactor volume at 600 ¢ªC with limited ability to generate hot and cold spots. The design and production methods of the TTmCSR lend itselves for mass production given the similarity with commercial Pd membrane hydrogen purifiers for semiconductor manufacturing industry featuring thousands of parallel tube in tube assemblies. Some of the issues and solutions are: 1) thermal expansion related stress addressed by tube connection at one end only, 2) small weld length per area of tube (no problematic diffusion bonding such as used for planar mchannels) and 3) low stress, simple manifolding. Noteworthy is that the discussed design lends itself to be transformed into a membrane reactor enabling to shift steam reforming operation to lower temperature and higher pressures. Experimental results interpreted to a COMSOL model will be presented.