Development of a new method for hydrogen recovery from lean gas mixtures (eg producer gas) using metal hydride slurries
During the present research period, the principle of continuous hydrogen recovery has been demonstrated. The effect of the reaction kinetics between hydrogen and the metal hydrides, mass transfer phenomena, hydrodynamics of this gas-liquid-solid system and physicochemical constants on the efficiency of this hydrogen recovery process are studied. The latter is necessary for the development of this new process for practical applications. On pilot-plant scale the hydrodynamics and the hydrogen absorption rates are investigated. A valve tray column serves as gas liquid contactor and experiments with pure hydrogen as well as with a gas consisting of nitrogen and hydrogen have been carried out. The presence of nitrogen results in a decrease of the hydrogen uptake rate without any loss in loading capacity. The absorption kinetics of hydrogen in metal hydride slurries suspended in inert silicon oil are studied independently in a stirred vessel model reactor. Two types of metal hydrides, LaNi(5) and LaNi(4.7)Al(0.3) are investigated. From the results it can be concluded that the reaction is first order in hydrogen and that the temperature dependence of the reaction rate is the same for both hydrides. For the description of the gas absorption in slurries, theoretical models, necessary for the design and development of large-scale hydrogen recovery processes, are developed. These models are also useful for the interpretation of the experiments.
Bibliographic Reference: EUR 12712 EN (1990) 195 pp., MF, ECU 8, blow-up copy ECU 25
Record Number: 199011002 / Last updated on: 1994-12-01
Original language: en
Available languages: en