GB1509184A - Hydrogen storage apparatus - Google Patents

Abstract

1509184 Hydrogen storage apparatus ASSOCIATED ENG Ltd 25 July 1975 [26 April 1974] 18485/74 Heading C1A A hydrogen storage apparatus comprises storage means 10 for storing metallic hydrides charged with hydrogen, a heat exchanger 12, 13 for heating the hydrides to evolve hydrogen gas, a gas path around which hydrogen gas can circulate and including the storage means, the heat exchanger and a duct 11, 14, 16 external of the storage means, a pump 15 for circulating gas around the path, and means (filter 18, valve 19, pipe 17, burner 20) whereby part of the circulated hydrogen may be withdrawn from the path. Preferred metallic hydrides are magnesium hydride and iron-titanium hydride. As shown in Fig. 2, container 10 contains a gas packed bed of particulate metal hydride up to a level 23, which in operation, forms a fluidized bed up to level 24. Above level 24 is a filter 25 permeable by hydrogen, but not by the particulate hydride. Duct 16 is connected within the container to a further filter 26, and connections 27 and 32 are made to the upper part of the container above and below filter 25 respectively, the latter enabling the container to be filled with fresh hydride; spent hydride is removed at 28. In operation, hydrogen gas with entrained particulate hydrides is circulated from the container, through duct 11, heat exchanger 12 and ducts 14,16 back to the container by pump 15. In the heat exchanger, the hydrides are heated by heat exchange with the hot fluid flowing through 13, and hydrogen is released in quantities dependent on the flow and/or temperature of fluid through side 13. Some hydrogen may be tapped off through filter 18, and valve 19 after use in burner 20, which may be a heater or heat engine. Spent hydride, being of higher density, accumulates in the lower part of container 10 and may be removed through 28. Container 10 may be removed and exchanged, or may be recharged either by circulating hydrogen therethrough, with coolant flowing through side 13 of the heat exchanger, or by passing hydrogen through the container via duct 16, connection 27 and valve 29. Fig. 3 (not shown) illustrates an apparatus in which a series of containers alternate with a series of heat exchangers; Fig. 4 (not shown) an apparatus in which the container includes an integral heat exchanger within the fluidized bed and Fig. 9 a multi-stage apparatus of similar form; Fig. 8 (not shown) an apparatus differing from that of Fig. 1 in that only hydrogen is circulated, and not entrained powder; Figs. 10 and 11 (not shown) an apparatus in which the storage container is formed as a large number of separate compartments, connected in sequence in the hydrogen circuit; and Figs. 12 and 13 (not shown) a modification in which the hydrides in the compartments are heated directly by the supply of fluid.