Application of a rubber particle profile control system in complex fault-block oilfield

When applied to middle and high permeability fault block reservoirs in Wenmingzhai and Weicheng Oilfield in the Middle and Later Periods, traditional profile control systems such as calcareous clay cement, particle, and polymer species were weakened time after time and profile control effect became worse. Interlayer and within-layer contradictions stood out so strongly that a new and economical profile control system must be developed. The new rubber particle profile control system was made up of rubber particles, suspension agents and polyacrylamide. Compatibility between rubber particle and pore throat in reservoirs were researched by gravel packing. Also, sealing ability of the system in sand pack tubes with diverse permeability was studied. The optimum injection concentration ratio was determined by studying the rubber particle with different sizes, suspending agent and polyacrylamide with diverse concentration. Field application in 9 water injection wells in Wenmingzhai and Weicheng Oilfield got 773 tons increment oil totally. The input/output ratio came to 1: 1.75. Application of rubber particle system was a step further technology of profile control. It showed an evident effect in sealing middle and high permeability fault block reservoirs. Correspondingly, oil wells were seen as obvious oil stabilizing and water cut control.