Patent attributes
A method of storing hydrogen involves forming an excavation in the earth and constructing a storage tank therein comprised of integrated primary and secondary containment structures. The primary containment structure composed of a plurality of joinable cylindrical segments, or pre-fabricated sections joined to form a cylinder within the excavation. The secondary containment structure formed by pumping a curable, flowable composition into the cylinder, allowing it to flow out the bottom and up the second annulus to the earth's surface, and then hardening; thereby encasing the primary containment structure. The bottom of the cylinder is sealed with the bottom assembly. The top assembly is attached to the cylinder and tubing and packer are run into the cylinder creating a first annulus between the cylinder and tubing. Top assembly is sealed, fluids circulated out, and the tank dried. Thereafter, the tank is capable of safely storing hydrogen gas.