Optimization And Application Of Pressure Recovery Well Test In Puguang Gas Well

At Present,Puguang gas field is the largest carbonate gas field in Sichuan of China,the main part type of gas field is high sulfur of atmospheric pressure with edge water and fracture pore,the characteristic of marine carbonate reservoir gas field with buried depth,high temperature,long well,strong heterogeneity,high content of sulfur,etc.Puguang gas field is also the gas origin of Sichuan to east as well as one of the most important energy development projects in China.In recent years,the exploration and development of the Puguang gas field have achieved a great deal of important information and data,these data has played a very important role to realize the reasonable development of Puguang gas field,continuous and stable yield as well as improve recovery factor.But because of the characteristic in the Puguang gas field has complex geological characteristics and conditions of gas reservoir,in the pressure of gas well recovery tests,according to the existing theory of numerical calculation and field test data statistical analysis,certain deviation have been found.To optimize the well test of gas well pressure recovery in Puguang gas field,one is to select the appropriate recovery time of well pressure,which is to reduce the risk of construction,and to ensure the quality of well test data.The two is to choose reasonable well test to explain the stable production time of gas well,ensure the accuracy and continuity of well test interpretation results,and provide accurate data for gas reservoir development.Three,the interference rule of adjacent wells in Puguang gas field is determined.When the pressure recovery wells are tested,the interference from adjacent wells is reduced to the minimum,so as to ensure the accuracy of well test data.The four is to use the water invasion boundary to reflect the well test curve,through the establishment of water penetration model,study and analyze the distance of the water invasion boundary of the gas well,adjust the gas well work system and put forward the related control measures in time.This study is of great significance for improving the energy recovery of the Puguang gas field,maintaining the sustained and stable production and the success of the East Sichuan gas transmission project.In this paper,based on the geological characteristics and reservoir information of Puguang gas field,and combined with a lot of well logging data,to establish related model,suitable shut-in pressure restore time and stable production time for Puguang gas field is studied,the adjacent well interference and gas well water invasion boundary distance is analyzed,and combined with the data analysis,the effect of wellbore liquid to gas well pressure recovery is evaluated.In view of the pressure buildup test requirements of Puguang gas field,this paper has carried out a series of research work,and obtained the corresponding research achievements,mainly includes the following aspects:(1)The geological characteristics and reservoir profiles of Puguang gas field were analyzed.The relevant data obtained by the actual scene,widely consult and search the related literature at home and abroad.Geological structure field overview,geological condition,reservoir properties and production situation of Puguang gas field were analyzed,and put forward the research direction and ideas of this paper.(2)The research on the analysis for the Puguang gas field shut-in pressure recovery time and stable production time is carried out.According to the relevant data obtained by field test and the data analysis results analyzed by the simulation software,Analyzed the different of shut-in pressure recovery time At of stable production time tp selected value of the minimum requirements,and effects of different stable production time tp on the derivative curve shape and explain parameters.(3)The research on the interference between adjacent wells interference and gas well water invasion boundary is carried out.Based on the principle of seepage mechanics,the interference model of adjacent wells and the mathematical model of water invasion gas wells are established.The distance between the interference pressure drop of the adjacent well and the water invasion boundary of the gas well is calculated.(4)Field application effect is analyzed.The shut-in time and stable production time are determined by analysis and comparison.The interference effect of adjacent wells,the effect of well bore liquid phase interference and the effect of water invasion gas well are evaluated and analyzed.