Research and application of asynchronous injection-production in ultra-low permeability horizontal well area

When using horizontal wells to exploit ultra-low permeability oil fields, the development effect is usually ensured by increasing the scale of fracturing reconstruction. However, it also leads to the increasing difference of seepage capacity between matrix and fracture, which makes it easier to see water in horizontal wells after water injection and difficult to recover after water cut rises. Therefore, asynchronous injection-production test was carried out in the ultra-low permeability horizontal well area, making full use of the artificial fracture of horizontal well as the high permeability channel, and performing oil-water replacement through full imbibition between high and low permeability layers, so as to improve oil recovery. On the basis of theoretical guidance, during the summary of practice, the main factors affecting the implementation effect of asynchronous injection and production are gradually analyzed, and the reasonable parameters in the implementation process are clearly defined, so as to explore a new treatment method for the middle and high water cut stage in the ultra-low permeability horizontal well area.