Storage of Natural Gas in the Reitbrook Cretaceous Reservoir.

To meet the seasonal and daily peak demand for gas, Hamburger Gaswerke GmbH needed storage capacity which was installed in the Cretaceous oil reservoir of Reitbrook, about 15 km southeast of Hamburg, by the Preussag/Mobil Oil Consortium. The oil reservoir was discovered in 1937 at a depth of about 650 m. By analysis of the production history by means of material balance calculations the input data for computing the volume-pressure behavior during the storage cycles were found. Based on multiple rate tests and pressure build-up analyses the flow capacities of the storage wells were derived numerically. Well stimulation and the installation of bigger tubing strings were taken into account. During the first two years of operation the volume-pressure behavior and the well capacities agreed well with the predicted data. No technical difficulties have been experienced to date.