Optimierung der permanenten Druckuber-wachung im Erdgasspeicher Puchkirehen

摘要

The gas field Puchkirchen in Upper Austria has been used for gas storage since 1982.The initial pressure measure-ment concept was to record wellhead pres-sures only.To maximise the capacity of the gas storage an increase of the reservoir pressure was necessary.The pressure increase in the reservoir and the verification ofthe Simulation model required a continuous and auto-mated recording of pressures measured at the wellhead and at reservoir depth.So far wellhead pressures have been recorded man-ually and subsurface pressures with memory gauges run on slickline.Bottom hole pressures are required to im-prove the reservoir model,to monitor the movement of the aquifer and to optimise the vertical lift correlations.For wells without bottom hole measurements it is possible to calculate bottom hole pressures using an op-timised vertical lift correlation from wellhead pressures.An evaluation of the reservoir Puchkirchen has shown that two continuous bottom hole measurements provide sufficient data to im-prove the reservoir Simulation model and the vertical lift correlations as well.Two different completion methods for permanent bottom hole pressure measurement are in use in the gas storage Puchkirchen at the moment.On one well the downhole gauge is hung off on wireline lowered in the tubing.This well is at the margin of the reservoir.Therefore it is mainly used to monitor the aquifer movement when injecting and producing.In the second monitoring well the pressure gauge is lowered as a permanent downhole gauge as a part of the tubing string.The cable is run to surface on the outer side ofthe tubing.The advantage of this completion is that the well still can be used as a storage well.With the project"Optimisation of Permanent Pressure Monitoring at the Puchkirchen Underground Gas Storage",a very efficient and cost effective concept of pressure monitoring has been realized.