UTILIZATION OF GASES FROM BIOMASS GASIFICATION IN A REFORMING REACTOR COUPLED TO AN INTEGRATED PLANAR SOLID OXIDE FUEL CELL: SIMULATION ANALYSIS

Abstract

One of the high-efficiency options currently under study for a rational employment of hydrogen are fuel cells. In this scenario, the Integrated Planar Solid Oxide Fuel Cell (IP-SOFC) is a new concept recently proposed by Rolls-Royce. The basic unit of a modular plant is the so called 'strip', containing an electrochemical reactor formed by a number of IP-SOFC modules, and a reforming reactor. For a better understanding of the behaviour of a system of this kind, a simulation model has been set up for both the electrochemical reactor and the reformer; both models follow the approach typically employed in the simulation of chemical reactors, based on the solution of mass and energy balances. In the case of the IP-SOFC electrochemical reactor, the model includes the calculation of the electrical resistance of the stack (that is essentially due to ohmic losses, activation polarisation and mass transport limitations), the mass balances of the gaseous flows, the energy balances of gaseous flows (anodic and cathodic) and of the solid. The strip is designed in such a way that the reaction in the reforming reactor is thermally sustained by the sensible heat of the hot air exiting the electrochemical section; this heat exchange is taken into account in the model of the reformer, which includes the energy balance of gaseous flows and of the solid structure. Simulation results are reported and discussed for both the electrochemical reactor in stand-alone configuration (including comparison to experimental data in a narrow range of operating conditions) and for the complete strip.

Keywords

Dates

  • Submission Date2004-05-07
  • Revision Date2004-09-27
  • Acceptance Date2004-10-14

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