Convegni ATI - Accesso riservato soci CTI

Autore: A. Casalegno, P. Grassini, R. Marchesi

Collana: BT - 34 - Mag 06 - Energy: production, distribution and conservation

Note:
In this work a method to evaluate methanol cross-over rate and operating condition influence is presented and qualified in term of measurement uncertainty. In the investigated range, the methanol cross-over rate results mainly due to diffusion through the membrane, in fact it is strongly affected by temperature. Moreover the cross-over influence on fuel utilization and fuel cell efficiency is investigated. The methanol cross-over rate appears linearly proportional to electrochemical fuel utilization and values , obtained by measurements at different anode flow rate but constant electrochemical fuel utilization, are roughly equal; methanol wasting, due to cross-over, is considerable and can still be higher than electrochemical utilization. The fuel recirculation effect on energy efficiency has been investigated and it has found that fuel recirculation gives more advantage at low temperature, but fuel cell energy efficiency results anyway higher at high temperature.