Operating Strategies for Fischer-Tropsch Tail Gas Recirculation on a 100 kW SOEC Reactor

Abstract

The emulated coupling of a 100 kW SOC reactor with an emulated tail gas recirculation of a Fischer-Tropsch reactor was investigated. Different syngas ratios (H2/CO) were studied, not only experimentally but also with the support of the in-house simulation framework from DLR, TEMPEST, which is specialized for transient simulations on electrochemical reactors. Different operating conditions were evaluated by: (i) adding CH4 at open circuit voltage (OCV) and under current and (ii) by performing an experimental ramp of the emulated Fischer-Tropsch gas composition into the inlet gases of the SOC reactor. These results allowed to evaluate the performance of the SOC reactor with the temperature profile along the cells and the stacks, as well as with the syngas ratio behavior. Operation strategies are analyzed and discussed with the aim to mitigate failure conditions on SOC reactors, while operating in transient conditions in the frame of syngas production via high temperature co-electrolysis.