Water Invasion Rule And Development Strategy Of Sebei-1 Gas Field

With the increase in the water production rate of the No.1 gas field in Sebei,the cause of water discharge is becoming more and more complicated,and the effusion wells are increasing year by year,and the daily gas production is gradually decreasing.In this paper,the?-4 and ?-3 layers with large geological reserves and serious water output are selected as the target layer group,and the production characteristics,sedimentary characteristics,reservoir characteristics,fluid characteristics and historical production data are used to carry out the production dynamics.According to the analysis,in order to solve the problem that the water body size is difficult to determine in the calculation of water influx,combined with the material balance method of water flooding gas reservoir and the calculation method of water influx of van Everdingen-Hurst,a new method for judging the size of water in gas reservoir is proposed.The target layer group was fitted with history,and the gas-water motion law and residual gas distribution law of the two layer groups were analyzed,and the development adjustment scheme was proposed.The main research contents and achievements of the thesis are as follows:(1)The dynamic analysis of the development of the ?-4 and ?-3 layers was carried out in four aspects:gas production capacity,effluent,sand production and water body energy.Through analysis of production dynamic data,analysis of water-gas ratio,growth trend,distance from the edge water,perforation horizon and other dynamic and static data,the water-gas ratio and time after gas well water see a "linear" relationship,water The intrusion method is mainly for the side water advancement.The composition of each layer is in 8 directions,and the water body size,water influx,water flooding index,sweep coefficient and B index in each direction are calculated,and the water energy in each direction of each layer group is comprehensively analyzed.(2)The history is fitted to the ?-4 and ?-3 tiers.The sub-simulation uses the Cartesian coordinate system under the corner grid.The plane is 25mx25m grid,and the vertical sandstone is divided into two units.The fitting curve of single well production,wellhead pressure and water production of the group has a good fitting effect.Furthermore,according to the results of numerical simulation,the law of gas-water motion and the distribution of residual gas are analyzed.Through the change of water saturation of each small layer,it is considered that the water intrusion method is in the background of the overall uplift of the edge water,and the local gas along the high permeability zone Rapid tongue advancement;the remaining gas reserves are defined as ?,?,?2,and IV according to the abundance of reserves and the degree of water saturation.The results show that the remaining gas is mainly composed of type ? reserves.(3)Based on the original old well production plan,four sets of development and adjustment plans were designed for the two tiers,including the deployment of new wells,drainage and gas production,the deployment of new wells while drainage and gas production,and the gas production plan in the flooded area.Comprehensive analysis of gas production,water production,final recovery and economic benefits,the final adjustment plan was to deploy 7 vertical wells in the ?-4 layer group and 6 vertical wells in the ?-3 layer group.