Technische Herausforderungen bei der untertagigeti Erweiterung des Erdgas-Kavernenspeichers Empelde

摘要

The gas cavern storage facility in Empelde came into Operation with three caverns between the early and the middle nineteen-eighties and is subject to a surface and subsurface extension since 2004. The subsurface extension comprises the con-struction oftwo new caverns (K4 is operated since 2009, K5 in leaching process since 2010) and the leaching extension as -well as repair works of both existing caverns K2 (since 2012 in gas Operation again) and K1 (is being re-leached since the end of 2012). The Volumetrie extension process of cavern K2 took place in three steps: flooding, re-leaching, gas re-filling. The flooding with water through a 4 1/2" tubing were imple-mented discontinuously alternating with phases of gas withdrawal through the annu-lus 41/2 "x 9 5/8 " in order to minimize the risk of hydrateformation. The length of the indi-vidual phases mainly depended on the gas demand/consumption of the storage users. Water injeetion has been made in a gas well-head pressure range above the hydrostatic pressure ofthe water column in order to keep it stable at any time and to keep the cavern pressure high. The cavern volume increased by 12% because ofthe flooding.