TITLE:
Application of Polymers in Low Permeability Formations
AUTHORS:
Juan Zhao, Caili Dai, Guang Yang, Jian Zhang, Hui Yang, Xinsheng Xue, Xiaodong Kang, Lixia Li
KEYWORDS:
Anionic and Cationic Polymer, Alternative Injection, Sealing Capacity, Water Displacement Recovery Increment
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.3 No.5,
May
7,
2015
ABSTRACT: 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.