Experimental study on potential tapping treatments with bidirectional profile control and water shutoff in oil and water wells

Profile control and water shutoff technology is used to improve the development effects of water-flooding in Daqing high water cut stage of early formations. In order to optimize the technical scheme of potential tapping treatments with profile control and water shutoff, three dimensional heterogeneous models is established to simulate the measures of water shutoff in oil wells, profile control in water wells and bidirectional water shutoff and profile control in oil water wells. A series of laboratory physical simulation experiments are conducted to study the influence of water shutoff and profile control succession and block radius on the recovery. The results show that displacement effect is the essentially same with profile control first and water shutoff first, but profile control first is effective early; and the effect treated by bidirectional water shutoff and profile control is better than that of the other two measures with which the recovery rate is 2% higher than these two measures; meanwhile, the profile control experiment results show that the effect of blocking is better with the increasing of block radius, but when the plugging distance is more than 10% of well spacing, the oil displacement effect of plugging radius increase is not that obvious. So it is suggested that the best radius of water shutoff range from 1 / 20 to 1 / 10 times of well spacing.