Patent ID: 8425149

Claim:
A method of storing and supplying hydrogen to a hydrogen pipeline comprising: compressing a feed stream of the hydrogen to produce a compressed hydrogen feed stream; injecting the compressed hydrogen feed stream into a salt cavern to produce stored hydrogen within the salt cavern through at least one conduit and withdrawing a stored hydrogen stream, composed of the stored hydrogen, from the salt cavern through the at least one conduit, the salt cavern having a residual brine layer located at a bottom region of the salt cavern and side regions extending upwardly from the bottom region of the salt cavern and the at least one conduit having at least one lower end located in an interior region of the salt cavern and spaced above the brine layer and from the side regions of the salt cavern; introducing the stored hydrogen stream after having been withdrawn from the salt cavern into the pipeline without removing carbon dioxide present within the stored hydrogen stream; maintaining at least a minimum quantity of the stored hydrogen within the salt cavern before, during, and between times at which the compressed hydrogen feed stream is injected and at which the stored hydrogen stream is withdrawn such that a stagnant layer of hydrogen is maintained that borders the interior region and has at least a bottom portion overlying the residual brine layer and a lateral portion situated along the side regions of the salt cavern, the stagnant layer having a carbon dioxide content that is a potential source of carbon dioxide contamination to the stored hydrogen stream; and limiting the flow rates and the velocities at which the compressed hydrogen feed stream is injected into the salt cavern and the stored hydrogen stream is withdrawn from the salt cavern such that the stagnant layer is not disturbed and the carbon dioxide contamination of the stored hydrogen stream from the stagnant layer is inhibited.