Design, development and hydrogen storage performance testing of a tube bundle metal hydride reactor

The present manuscript reports the experimental studies on a tube bundle reactor (TBR) designed for metal hydride (MH) based hydrogen storage system. The TBR comprising 19 MH tubes is designed to operate at low temperature and moderate pressure (273–353 K, up to 95 bar) with a projected storage capacity of ~385 g hydrogen. Each MH tube is packed with 1.35 kg of La0.8Ce0.2Ni5 constituting 26.5 kg active material. Water at a flow rate of 0.9–1.5 m3.h−1 was circulated through the shell side of the reactor to serve as heat transfer fluid (HTF) during absorption and desorption. Outcomes of the parametric investigation indicated that the favourable absorption temperature and pressure were in the range of 10–20 bar and 283–293 K, respectively. The reactor was able to store 369.09 g (1.39 wt.%) hydrogen within 1372 s at 20 bar and 293 K. Promising desorption regime was identified as 323–343 K necessitating only 0.8–1.7 kW average heating rate. The time required for desorption completion (t90%) was at par with published results. The estimated energy efficiency of hydrogen storage was in the range of 58–64 %.