Performance of 1.5 Nm3/h hydrogen generator by steam reforming of n-dodecane for naval applications

Liquid hydrocarbons conversion into hydrogen rich gas is a central process step in fuel processors for auxiliary power units (APUs) for naval applications. Diesel, together with gasoline, is the preferred fuel for these applications. The CNR-ITAE has developed an hydrogen generator based on steam reforming (SR) of n-dodecane (n-C12H26) as surrogate of diesel, designed for a maximum hydrogen production of 1.5 Nm3/h. The prototype consists of an integrated catalytic reactor coupled with heat exchanger, static mixer, water-dodecane and recycle reservoirs, manual/automatic valves, pressure regulators/transducers, flow meters, and ancillaries. The unit has been engineered, focusing every single component and the system integration, to meet the requirements of small size and volume, improving thermal/mass transfer and system efficiency. This study reports the performance of the hydrogen generator with a commercial Rh-based catalyst, packed on the steam reforming reactor. Experimental tests were carried out at a molar ratio steam to carbon (S/C) of 2.5, under a gas hourly space velocity (GHSV) of 3500 h-1, as derived from preliminary investigations in laboratory scale. Total conversion of n-dodecane and absence of carbon deposition phenomena, were observed. The syngas produced (H2/CO = 4.7) was adequate to feed a Solid Oxide Fuel Cell (SOFC).