The Effect of Heat Supply on Diesel Evaporation as the First Step of Hydrogen Production

Evaporation of diesel fuel is an important stage in the diesel reforming processes. Thermal decomposition of the heavy feedstock that occurs primarily in the high temperature domain of the evaporation process leads to carbonous material formation and may plug the evaporator. The diesel evaporator design is one of the key parameters to minimize carbon formation. The operating conditions must be optimized as well. In this study, the evaporation heat was supplied by two different ways. In the first evaporation system, the evaporation heat of the diesel fuel was supplied by an electrical furnace. In the second system, diesel was evaporated in a tube-and-tube heat exchanger via indirect heat supplied by hot nitrogen gas. The latter case was chosen to simulate the utilization of fuel reforming off-gases. Results indicate that evaporation by the hot gases results in much lower thermal decomposition of the diesel fuel compared to the utilization of the electrical energy. (authors)