Method for initiating operation of an underground storage cavity for low-boiling hydrocarbons and an installation for the storage of low-boiling hydrocarbons

摘要

Method for setting in operation an underground storage cavity (1) intended to receive a hydrocarbon maintained in liquid form at a very low temperature, under 0 DEG C, the cavity (1) being formed in phreatic water (5) and comprising an internal liquid-tight coating (2), the process comprising the steps of draining the water, during an initial phase, till the phreatic water (5) is brought to a level lower than the cavity (1), then introducing the liquid hydrocarbon in the cavity while continuing drainage so that the underground reaches a temperature lower than 0 DEG C, and finally stopping drainage in order to form around the cavity an ice barrier. The invention also discloses an underground storage plant comprising a cavity (1) intended to receive a hydrocarbon maintained in liquid form at a very low temperature under 0 DEG C, the cavity (1) being formed in a phreatic water layer (5) and comprising an internal liquid-tight coating (2) wherein the coating (2) comprises at least a carrier structure formed of independent voussoirs (22) capable of a relative displacement to each other, and a deformable sealing membrane (24) supported by said structure and defining the inside of the cavity (1).