Patent ID: 8735008

Claim:
A fuel cell system comprising: a fuel cell stack for generating electrical energy by reacting oxidant and mixed fuel to produce a cathode output stream comprising moisture and non-reacted oxidant, and an anode output stream comprising non-reacted fuel and carbon dioxide, and for discharging the non-reacted fuel, the non-reacted oxidant, the moisture, and the carbon dioxide; a mixer for preparing the mixed fuel by mixing at least a portion of the non-reacted fuel and the moisture with concentrated fuel, and for supplying the mixed fuel to the fuel cell stack; a fuel supply unit for supplying the concentrated fuel to the mixer; an oxidant supply unit for supplying the oxidant to the fuel cell stack; a first gas-liquid separator for receiving the cathode output stream and the anode output stream, separating the non-reacted fuel, the non-reacted oxidant, and the moisture into a first gas and a first liquid, discharging the first gas, and supplying the first liquid to the mixer; a first heat exchanger between the first gas-liquid separator and the mixer, the first heat exchanger for receiving the first gas, cooling and partially condensing the first gas into a first fluid, and discharging the first fluid; and a second heat exchanger between the mixer and an inlet of the fuel cell stack.