- 9:45 AM

Experimental Demonstration of a Thermally-Integrated Microchannel Network

Angela M. Moreno and Benjamin A. Wilhite. Department of Chemical, Materials and Biomolecular Engineering and Connecticut Global Fuel Cell Center, University of Connecticut, 191 Auditorium Rd, Unit 3222, Storrs, CT 06269

Microreactors and microchannel networks enable compact, thermally efficient multi-stage reforming of hydrocarbon fuels to hydrogen gas, as part of an overall portable-power system. Theoretical and experimental studies of microchannel networks coupling endothermic and exothermic processes indicate that optimal efficiencies are obtained by using low thermal conductivity construction materials (e.g. glass, ceramics).1-3

Our research group is developing a new class of ceramic microchannel reactor, combining the benefits of precision machining and ceramics extrusion. An extruded ceramic microchannel network is combined with a precision-machined distributor to realize complex distribution patterns which allow integration of two or more processes within a monolithic unit. This novel technique presents the following advantages; (i) ease of catalyst introduction, (ii) flexibility in material thermal conductivities, and (iii) space-separation of process flows in a variety of radial distribution patterns.

This talk presents the construction and demonstration of a prototype mini-channel reactor based on this new microchannel reactor design. The device is comprised of machined brass distributors designed to evenly distribute two unique fluids in a checker-board pattern among a 3x3 network of parallel mini-channels cut from a stock cordierite monolith (72 cpsi). The resulting ceramic mini-channel will be investigated in order to: i) perform simple heat transfer studies between non reacting fluids to quantify transport rates and verify 1-D models, ii) introduce a catalyst into individual channels by traditional wash coating methods and iii) carry out high-temperature heat transfer experiments between reacting fluids by using methanol as a fuel for conversion to hydrogen with appropriate catalytic micro channel networks. Experimental results will serve as validation of concept for the device as a new class of thermally integrated micro-reactors and will provide the basis for the creation of a powerful fuel reformer design.

1Moreno, A.; Murphy, K.; Wilhite, B. Parametric Study of Solid-Phase Axial Heat Conduction in Thermally-Integrated Microchannel Networks. Industrial and Engineering Chemistry Research. Article In Press.

2Terazaki, T.; Nomura, M.; Takeyama, K.; Nakamura, O.; Yamamoto, T. Development of Multi-Layered Microreactor with Methanol Reformer for Small PEMFC. Journal of Power Sources 2005, 145, 691.

3Kolios, G.; Glockler, B.; Gritsch, A.; Morillo, A.; Eigenberger, G. Heat-Integrated Reactor Concepts for Hydrogen Production by Methane Steam Reforming. Fuel Cells 2005, 5 (1), 52.