红河油田长8油藏CO_2泡沫剂配方的研究

Research on CO_2 foam formula of Chang-8 reservoir in Honghe oilfield

针对红河油田低渗裂缝性储层地层能量不足、注CO2会发生气窜的问题,优选了CO2泡沫起泡剂和稳泡剂,确定了泡沫剂配方由起泡剂AOS、咪唑啉、BS-12和稳泡剂烷基醇酰胺组成,其组分配比为38:19:38:5,泡沫剂最佳使用浓度为0.5%,发泡体积>540 mL,析液半衰期>6 min,泡沫半衰期>10 h,泡沫稳定性能优越,泡沫阻力因子可达28.684,封堵性能较好。CO2泡沫在高渗透率岩心中的阻力因子较大,说明泡沫更易封堵高渗储层及裂缝,可有效解决注CO2的气窜问题。

Due to the formation energy shortage and gas breakthrough of COs injection in Honghe oilfield, the foam agent and the foam stabilizer of CO2 foam are optimized, and the foam formula is determined to be composed of foam agent AOS, imidazoline, BS- 12 and alkanolamide whose proportion is 38：19：38：5. Foam optimum concentration is 0.5 %, foam volume is over 540 mL, drainage half-life period is over 6 minutes and foam half-life period is over 10 hours. Foam resistance factor can achieve 28.684 with good stability and sealing characteristics. CO2 foam with higher resistance factor in high permeability rocks shows that the foam is more suitable for sealing high permeability formation and fracture and the gas breakthrough of CO2 injection could be solved effectively.