Study on a Polymer Profile Control Agent with Controllable Swelling Time
Keywords:Controllable swelling time, Polymer, Profile control agent, Shell structure, Self-thickening.
AbstractThe study provided a microsphere profile control agent, which can smoothly go deep into the stratum by using the hydrophobic shell structure as the “protective film”. While the solution time in simulated brine was prolonged, water molecules went deep into the inside of the microsphere particles through the pore structure, and combined with hydrophilic groups. Because of the combination, the microsphere polymer started to swell, and opened the shell into long chain for days, and then at the end, its hydrophilic-hydrophobic block groups were all exposed in the solution, which resulted in self-thickening property. The dissolution time after entering into the stratum, i.e. the shell “rupture” time can be controlled by adjusting the carbon chains length of hydrophobic groups in the synthetic process. The agent can not only prolong the depth of plugging and provide a stable plugging rate, but also enlarge the water swept volume after dissolution. This method can stabilize the oil production and control the water cut. The function of delayed thickening ability makes the stratum sealed but kept at a certain permeability.
Yao CJ, Lei GL, Li L, Gao XM. Selectivity of pore-scale elastic microspheres as a novel profile control and oil displacement agent. Energ Fuel 2012; 26(8): 5092-5101. https://doi.org/10.1021/ef300689c
Pu WF, Wen CL, Liu R, Jin FY, Wang CY, Liao ZC. Evaluation of a novel profile control agent for enhancing an oil‐recovery application. Appl Polym 2016; 133(32): 43756. https://doi.org/10.1002/app.43756
Zhao FL, Zhang GC, Sun MQ, Xie TC, Wang FT. Studies on channel plugging in a reservoir by using clay as a profile control agent in a double-fluid method. Acta Petrol Sinica 1994; 15(1): 56-65.
Lu XG, Wang SX, Wang RJ, Wang HG, Zhang S. Adaptability of a deep profile control agent to reservoirs: Taking the Lamadian Oilfield in Daqing as an example. Petrol Explor Dev 2011; 38(5): 576-582. https://doi.org/10.1016/S1876-3804(11)60056-6 He Y, Xiong S, Yang Z, Ruan X, Gong Y. The research on cross-linking polymer gel as in-depth profile control agent. Petrol Sci Technol 2009; 27(12): 1300-1311. https://doi.org/10.1080/10916460802455236
Hu XD, Wang J, Liu PP, Experimental research on thermostable deep oil profile control agent. Adv in Fine Petrochem 2010; 10:5-9.
Liu PD, Zhang S, Feng AL, Qin J. Research of a retarding crosslink weak gel for conformance control and displacement and its performance evaluation. Oil Drill & Pro Tech 2013; 35(3): 90-93.
Jiang WD, Zhang J, Kang XD, Lu XG, Li Q. Chinese Patent 103342998A.
Li CQ, Li JP. Chinese Patent 102533240A.
Zheng YL. Chinese Patent 101260293.
Epifanio M-Z, Gilberto E-P. Mass transfer resistance at the boundary of a fractured porous medium. Int J Petrol Tech 2014; 1(1): 3-7. https://doi.org/10.15377/2409-787X.2014.01.01.1
Durmaz S, Okay O. Acrylamide/2-acrylamido-2- methylpropane sulfonic acid sodium salt-based hydrogels : synthesis and characterization. Polym 2000; 41(10): 3693- 3704. https://doi.org/10.1016/S0032-3861(99)00558-3