Experimental research of chemical flooding after polymer flooding

In view of Suizhong 36-1 oil field, this paper conducted physical simulation experiments of the binary compound flooding after polymer flooding, high concentration polymer flooding after polymer flooding, equal concentration polymer flooding after polymer flooding. Contrast enhanced recovery effects, and the results show that compared with the equal concentration polymer flooding after polymer flooding the recovery efficiency of the high concentration polymer flooding after polymer flooding increased by 1.28%. The final total recovery efficiency of the high concentration polymer flooding after polymer flooding is 46.22%; Compared with the equal concentration polymer flooding after polymer flooding recovery efficiency of injecting the binary system after polymer flooding increased by 21.35%, and the final recovery of the binary flooding after the polymer flooding is 66.29%; In the stage of the binary compound flooding, the contribution of the recovery efficiency to the final recovery of the total process is 47.49%.The high permeability layer contributes 57.18%, the infiltration layer contributes 32.72%, the low permeability layer contributes 10.1%. Although the contribution value of the low permeability layer is small, the recovery efficiency of the low permeability layer rises most obviously. The recovery efficiency of the low permeability layer at the end of the binary flooding was 2.57 times than that at the end of the polymer flooding, and it can be seen that the binary flooding drives the residual oil effectively after the polymer flooding. Combining with the contrast of economic property, binary compound flooding is a typical and preferred way of chemical flooding after polymer flooding for the offshore blocks. © 2016 UK Simulation Society. All rights reserved.