Numerical Simulation Of Natural Gas Flooding In Deep Clastic Reservoir In Lunnan Tarim

The exploitation of block 3 and block 10 of Lunnan Oilfield Tarim began in 1989,it has experienced a higher oil production stage with greater well-space,a balance oil production stage with reasonable well-space,and a lower oil production stage with smaller well-space.Currently,the water cut of the two blocks is extremely high.Therefore,in order to further increase the oil production rate of the two blocks,the injection of natural gas to improve oil recovery has been proposed.This paper firstly conducted the EOR mechanism of natural gas flooding,the formation characteristics of Lunnan fields,and the oil production history of the two blocks.The feasibility of natural gas flooding in the Block 3 and Block 10 is evaluated.The specific steps include model establishment,parameter input,historical matching,residual oil evaluation,injection parameter optimization,and development scheme design.Results show that the natural gas flooding is suitable for the EOR of the two blocks.It is shown that the oil recovery ratio of natural gas flooding is significantly higher than that of water flooding,nitrogen flooding,and carbon dioxide flooding.For block 3 and block 10,the natural gas-water alternate displacement(WAG)is the optimal option.The application of WAG flooding simulation was conducted for 15 years.Compared with the original development scheme of the original well pattern,the average recovery of the two blocks is increased by 7.37%,which provides a reference basis for the field application of Lunnan natural gas drive in Tarim.