Study and Application of Micro Bubble Temporary Plugging Technology

The conventional method to plug channeling with cement is apt to pollute formation,and particle-type temporary blocking agents usually have short effective period.We tried to solve the two problems with micro bubble temporary plugging.The properties(shear thinning behaviors,static plugging,dynamic pollution and flow back)of micro bubble treatment fluid were evaluated by lab experiment.The results proved that the micro bubble treatment fluid had certain shear thinning behavoir,and strong plugging ability.At the temperature of 120℃,back pressure of 0.5 MPa and differential pressure of 5 MPa,the leakage of the fluid was 0.It had good flow back ability,and caused little damage to reservoir.Core permeability recovery ratio was up to 96.1% after pollution by it for forty-eight hours.The technology has been used on four wells in Jidong Oilfield.The working pressure was controllable during injection of micro bubble plugging fluid.The treatment resulted in a cumulative oil increment of 10 314 t,and the average water cut had declined by 17.6%,the effects of increasing oil production and reducing aquifer yield were obvious.Its application indicated that it had low operation risk,strong plugging ability,good reservoir protection effect,and long period of validity.