Condensate Production Prediction In The G Area Reservoir With Condensate Gas Cap Using Cyclic Gas Injection Method

G-zone reservoir with condensate gas cap have both condensate gas cap and oil ring.As the formation pressure drops,the condensate gas cap will condense a large amount of condensate,and the cyclic gas injection method can be used to maintain the formation pressure and reduce the loss of condensate.Accurately predicting the production of condensate is the basis for formulating a reasonable reservoir development policy.Therefore,it is of great significance to establish a condensate production prediction method in a reservoir with condensate gas cap using cyclic gas injection method.The G-zone reservoir with condensate gas cap adopts the development method of oil and gas simultaneous production and cyclic gas injection,and uses barrier water injection to prevent oil and gas channeling,which makes the condensate production prediction of G zone reservoir more complicated.Firstly,based on the numerical simulation method,the phase change characteristics of the gas cap fluid and the change of the condensate under the cyclic gas injection method are analyzed,and the key parameters are obtained to provide data for the subsequent calculation of condensate production.Secondly,using the reservoir engineering method,the condensate production prediction model of the condensate gas cap reservoir under the cyclic gas injection method is established.The model considers the high velocity effect of the near-well zone and the material balance method considering cyclic gas injection and barrier water injection is used to assist the solution.Thirdly,the impact of different production parameters on the development effect is carried out,and the single factor impact and multi-factor impact are carried out respectively to determine the relationship and range of the influence of each parameter on the degree of condensate recovery and the total recovery.Finally,combined with the analysis of influencing factors,the condensate production under the cyclic gas injection method in the G-zone reservoir with gas cap is predicted.The results show that the calculation results of the condensate production prediction model are accurate.In the actual production,in order to ensure the maximum recovery of condensate oil and oil ring oil,in the initial stage of oilfield development,under the premise of ensuring no gas channeling and water flooding,try to maintain a high oil production rate,at the same time,in order to prevent premature gas channeling and water flooding,gas production rate and injection-production ratio can be appropriately increased,but it is not suitable to increase too much.The condensate production prediction curve based on the numerical simulation method and the reservoir engineering method can provide a basis for the efficient development of similar reservoirs.