Hydrogen is being considered very seriously as an alternative, renewable energy carrier for use in internal combustion engines or fuel cells. However, despite some recent advancement, hydrogen storage is still a major concern. Here are three main ways that hydrogen can be stored as a compressed gas, in liquid form, in metal hydrides and in carbon nanotubes. Today's state of the art for hydrogen storage includes 5000- and 10,000-psi compressed gas tanks and cryogenic liquid gas tanks for on-board hydrogen storage.
The energy density of gaseous hydrogen can be improved by storing hydrogen at higher pressures. An assessment of the hazard posed by this method of Compressed Hydrogen Storage is presented in this paper. Based on the risk identification, it is proposed that risks can be mitigated and controlled by taking various measures, such as optimizing vessel structure, correct selection of materials, and mitigation of ignition sources, on-line safety monitoring, safe operation and management. Safe operation can be done by multi-layered stationary hydrogen storage vessels and flames obtained in these tanks depended not only on the nozzle diameter but also on the release pressure.
In the case of slit nozzles, the flame length depended on the length of the shorter side of the slit nozzle. The radiation from the hydrogen flame could be predicted from the flow rate of the gas and the distance from the flame
