Selection of Oil Displacement System for Type III Reservoir in Daqing Oilfield and Its Evaluation

Li Xia;Zhang Xiaoqin;Zhou Hao;Guan Wenting;Wang Wei;Research Institute of Exploration and Development,Daqing Oilfield Co.Ltd.;

low permeability reservoir;;polymer flooding;;Asp flooding;;performance evaluation;;displacement effect

At present low permeability reservoirs(Type III Reservoir)in Daqing Oilfield have been still produced by water flooding,recovery percent of reserves was low for water flooding,tapping the potential of remaining oil was high,it was an important replacement potential in Daqing Oilfield in the future.For establishing the technology to improve oil recovery in the low permeability reservoirs as soon as possible,through indoor experiments,a low salt resistant polymer,binary compound system and the ternary compound system were screened,performance of the system was evaluated.The result shows that under the same condition,the oil displacement effect of ternary compound system is obviously better than that of the polymer and the binary composite systems.The recovery percent of 800 ×104 salt resistant polymer has 5% more than that of 900×104 polymer,it can save the polymer injection amount by 60%.For ternary compound system with high alkali,it is suitable for preparation with 800×104 salt resistant polymer,it can save more than 50% of the polymer injection amount.The existed low molecular weight polymer has shortcomings in its performance,it needs to be improved by research and development for suitably used in the low permeability reservoirs for the purpose of improving its viscosity and stability for obtaining better oil displacement effect.