Research On Reasonable Process Parameters Of Draining Water Gas Recoveryfrom Plunger Gas Lift In Suxi District

With the rapid development of the national economy,the demand for natural gas in China is increasing year by year.The Sulige gas field is the largest natural gas field in China.However,one of the difficulties in the Sulige gas field is the high water content in the gas reservoir,which is in the production process.It is easy to form bottom effusions and affect gas well productivity.Therefore,the research on the draining water gas recovery of the plunger gas lift in Sulige gas field becomes more and more important,and it is also urgently needed to solve the practical production problem.In this paper,theoretical analysis and field test analysis are combined to perform in-depth research on the implementation of plunger gas lift in the Suxi District.Finally,it is concluded that the main gas production interval in the Sulige gas field is the Upper Paleozoic Permian formation.The he 8th and the shan 1st section of the reservoir are in the stratum and the buried depth is 2800m-3700m.The accumulation model belongs to large lithologic gas reservoirs.The four stages of a plunger's motion cycle are analyzed,and a dynamic mathematical model of plunger gas lift is established and the differential equation is solved.The gas production from gas wells is positively correlated with gas production,rock permeability and porosity,and negatively correlated with gas saturation.The selection conditions for the use of plunger gas lift in the Suxi district are:the gas depth is about 3600 meters;the water/gas ratio is less than 2m~3/10~4m~3,and the daily gas production is 0.1×10~4m~3-0.3×10~4m~3.Within 8 hours,casing pressure is raised from 2 MPa to above 5 MPa or over 5-10 MPa gas wells.This article also summarizes the reasonable process parameters of the plunger gas lift:When the pressure difference of the oil pressure of oil vocabulary is less than 1MPa,it shows that the plunger can maximize the liquid accumulation and the plunger can operate normally.At this time,it must be ensured that at least 2 hours will be shut off;the minimum time for the well is a one-hour work system.