Application of viscoelastic agent profile control in Jurassic reservoir of Jiyuan oilfield
The Jurassic reservoir of Jiyuan oilfield is located in the central western part of the Ordos Basin and belongs to a low-permeability sandstone oil reservoir.The oil and water movement in the reservoir is dominated by pore type seepage.After entering the middle and late stages of development,the phenomenon of water flooding in oil wells is serious.Jiyuan oilfield has successively applied profile control systems such as"cross-linked polymer gel+ bulky particles","PEG single-phase gel profile control and displacement agent"and"nano microsphere"to profile control water injection wells in Jurassic reservoirs.Although some results have been achieved in reducing reservoir decline and controlling water cut rise,the effect on water cut reduction in water flooded wells is not obvious.In recent years,Jiyuan oilfield has conducted research on the mechanism of water flooding in Jurassic oil wells,op-timized the profile control system,and selected a new viscoelastic agent for profile control.Both indoor evaluation and on-site implementation have proven that the performance of the viscoelastic agent is reliable.From 2021 to 2022,after using viscoelastic agents to profile control 56 flooded well groups in Jurassic reservoir of Jiyuan oilfield,the monthly decline rate of the well group decreased from 2.59%to 1.01%,and the monthly water cut increase decreased from 0.61%to 0.08%.At the same time,the water content of most water flooded wells has significantly decreased,and the average effective period of single well group oil increase has reached 226 t.Based on the oil price of $45/barrel,the input-output ratio is 1.00∶2.11,and the implementation benefits are good.
viscoelastic agentprofile controlJurassic reservoiroil well floodedwater flo-oded well treatment
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维普
