关键词: 聚合物驱, 微生物降解, 物理模型, 模拟实验, 低渗透率油藏, 提高采收率

Abstract: A kind of polymer degrading microbe JHW-31 was selected from Daqing Oilfield.The microbe was inoculated and cultured in the culture medium confected with polymer and a little sucrose for 7 days under the condition of pH 7.2 and temperature 45℃.The viscosity reduction rate of the polymer reached 92.1%,and the molecular weight of the polymer decreased from 18×10⁶ to 0.5×10⁶.The gross of the polymer decreased a little bit.Nuclear magnetic resonance test result indicated that the content of the amide group in the polymer decreased from 74.6% to 60.8%,while the carboxylic acid group increased obviously.This kind of microbe could be confected with the surfactant microbe T11 and was compatible with the stratum water.The physical simulation indicated that the oil recovery increased by 5.4% when the microbe was used after polymer flooding.If the ASP flooding was used after microbe flooding,oil recovery could increase by 9.7%.In the heterogeneous core,this microbe can mobilize more remaining oil in the low-permeability zone and clean out the resorted polymer.

Key words: polymer flooding, microbe degradation, physical model, simulation experiment, low-permeability reservoir, enhanced oil recovery