Author(s)

Juan Zhao^1,2, Caili Dai³, Guang Yang^1,2, Jian Zhang^1,2, Hui Yang⁴, Xinsheng Xue^1,2, Xiaodong Kang^1,2, Lixia Li^1,2

¹State Key Laboratory of Offshore Oil Exploitation, Beijing, China.
²CNOOC Research Institute, Beijing, China.
³China University of Petroleum (East China), Qingdao, China.
⁴Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, the Chinese Academy of Sciences, Beijing, China.

For low-permeability sandstone reservoir with big channel, we researched the novel deep profile method alternative injection of anionic and cationic polymer. Evaluating various factors on adsorption capacity through lab test, the results show that with the increase of temperature, the adsorption capacity decreases and the cationic polymer is easier to be absorbed. With the increase of salinity, adsorption time or polymer concentration, the adsorption capacity increases. The adsorption equilibrium concentration of cationic polymer is 1500 mg/L; adsorption equilibrium time is 8 h. The adsorption equilibrium concentration of anionic polymer is 1000 mg/L; adsorption equilibrium time is 6 h. Physical simulation experiment shows that alternative injection of anionic and cationic polymer is better than injection of single polymer, and preferential injection of cationic polymer is better than preferential injection of anionic polymer. With the increase of injection rounds, sealing capacity gets better, but in view of cost, the rounds should not be more than 3. The profile control technique can obviously enhanced oil recovery, and water displacement recovery increases 41%. 2 wells were tested successfully in Henan Oilfield in June 2010. Approximate 154.47 tons of incremental oil was obtained with 2% water-cut decrease.

Anionic and Cationic Polymer, Alternative Injection, Sealing Capacity, Water Displacement Recovery Increment

Zhao, J. , Dai, C. , Yang, G. , Zhang, J. , Yang, H. , Xue, X. , Kang, X. and Li, L. (2015) Application of Polymers in Low Permeability Formations. Journal of Materials Science and Chemical Engineering, 3, 37-45. doi: 10.4236/msce.2015.35005.