Research On Drainage Gas Recovery Measures Of Gas Well In Edge Of Main Reservoir Of PG Gas Field

PG gas reservoir with partial fracture existed is carbonate rock pore type,high sulfur with edge and bottom water drive gas reservoir.The characteristics of PG gas reservoir is complex, which is deeply buried with higher H2 S and CO2 content,large thickness and strong heterogeneity. Since June 2012, water have been seen in P105-1H、P103-1、P105-2、P103-4 and P104-3 well.The water gas ratio is high and edge and bottom water invasion has great influence on the gas filed development.Making full use of the production data, well logging data and geological data, the classification of water source are analyzed. Water source including condensate water, stratum movable water, edge and bottom water are identified.The stratum pressures is evaluated by the extrapolation of material balance method in water drive gas reservoir and the type of water invasion is identified by means of cumulative production method and standard template method. What’s more, with influence function combined with the productivity equation of gas reservoirand grey system prediction method applying, water yield of water invasion risks well is predicted. Effect of the edge gas well water invasion on gas field development is also evaluated.According to the condition of wellhead, different method such as visual method, critical liquid carrying flow rate method and dynamic parameters method in gas wells were comprehensively used to carry on effusion judgment so that the basis for drainage gas technology type selection and process parameters design will be provided.Based on research in principle, characteristics and the adaptability of several kinds of common drainage gas recovery technology,they are preliminarily chosen. In addition, the economic indicators are comprehensively considered. It is turned out that concentric capillary foam drainage gas recovery technology is the most applicable.Therefore,foam scrubbing agent is chosen for designing the technology parameters.The results of this study has certain guiding significance for foam drainage gas technology of gas well in edge of main reservoir of PG gas field. The implementation of foam drainage gas recovery technology result in improving the recovery of gas reservoir and realize the economic and effective development of PG gas field.