The remaining spent fuel is recycled and burned to increase the temperature of the exhaust stream coming from
the gas turbine, which is then used to heat up the fuel reformer. NG has to be added in order to achieve a
temperature of 750°C at the hot side of the reformer reactor to enhance the endothermic reforming reactions. Gas
turbine and spent fuel are preheated with saturated water bled from the IP drum of the HRSG.
In both configurations, the cathode exhaust stream is cooled by the HRSG, so that the MCFC operates in a
hybrid configuration releasing exhaust heat to the steam bottoming cycle. This allows improving the efficiency (at
least before CO2 capture, as will be clarified in the discussion of results) with respect to the level of the original
combined cycle. Moreover, in both cases the cooled exhaust gas can be sent to the stack (as shown in Figure 3 and
Figure 4) or partially recycled to increase the CO2 concentration on the MCFC cathode side and enhance the fraction
of CO2 captured; this option, which has been considered in previous works [3,4] based on internal reforming type
MCFCs, is not addressed here because exceed the proper range of operating conditions