Abstract
Keywords: fuel-cell, ammonia, hydrogen, COx free fuel, exergy analysis.
In this paper, the authors have described a fuel-cell electric vehicle for trial purposes with the hydrogen generation system fueled with ammonia for compact vehicles. The system consists of a dissociator with Ruthenium/ Alumina catalyst, a heat exchanger and an ammonia separator to remove residual ammonia. The dissociation system compactly unifies the heat exchanger and the dissociator to effectively rise the temperature of the system by installing some alumina balls just before catalyst. The cruising time is about 160 minutes in the system. If the concentration of residual ammonia in the dissociated gas becomes 13 ppm or more, the residual ammonia will poison the proton exchange membrane (electrolyte) of the fuel-cell, and cause the fuel-cell to decrease the output. The residual ammonia in the separator must be removed, because the ammonia concentration in the dissociated gas reaches 13 ppm after 160 minutes in the experiment. If the residual ammonia is removed, the system can be expected to be about 2.5 times of the cruising time. In addition, it is estimated that the fuel-cell will probably work for about 20 hours with 10 litters of liquid ammonia. The authors have calculated a heat balance and an exergy of the hydrogen generation system for the improvement of the system and found the efficiency of each device. The heat of 45kJ after the dissociation was used for the heat exchanger and evaporator for the total efficiency improvement. Safety and further improvement of service time are necessary, but it can say that the fuel-cell electric vehicle fueled with ammonia is one of the vehicles which are clean of the future.