Research On Multiphase Production Split Method And Bottomhole Pressure Conversion Method Of Gas Wells Under Unified Metering Conditions

Recently,an increasing number of oil and gas fields in China have adopted multi-well metering system instead of single-well metering system.However,the unknown wellhead production of each well in current multi-well metering system results in the incapability to calculate the bottom hole pressure,which consequently makes it difficult to understand the entire actual production conditions.In addition,the installation of downhole throttles will further increase the difficulty in bottom hole pressure calculation.These conditions have affected the estimation and evaluation of dynamic reserves and hampered further understanding and development of the blocks.In view of the above two prominent problems in Hechuan field,the following work has been done to provide theoretical support and convenience for the follow-up research.The Beggs& Brill correlation is used to proposed a mathematical model for calculating the pipe flow,and the data of a real well are substituted into the proposed mathematical model for verification calculation.Based on the proposed calculation model of pipe flow,a production splitting method was proposed.A variety of throttle nozzle flow models were studied.Based on the Perkins pressure loss calculation formula and the improved temperature calculation model,the throttle pressure loss calculation model was proposed,and the sensitivity analysis was conducted.The production splitting and flowing pressure calculation model with downhole throttle were realized by programming,and the corresponding calculation software was compiled to provide convenience for later use.The well group data and production data on site were substituted into the model to carry out production splitting and flowing pressure calculation with downhole throttle.Using Blasingame,Agarwal-Gardner and NPI modern production decline methods,the dynamic reserves of gas Wells are calculated.In order to accurately calculate the dynamic reserves of gas Wells,this paper proposed a production splitting method and a calculation method of bottomhole pressure with downhole throttle in view of single well production loss and installation of downhole throttle.The research results have certain reference value for field application.