新型层内生气泡沫体系优选与性能评价

Optimization and performance evaluation of new in-situ gas generating foam system

针对常规泡沫体系稳定性差、调剖能力有限的问题,采用Waring Blender法筛选出一种适用于层内生气调驱技术的泡沫封堵体系,并通过长填砂管实验和微观驱油实验对优选体系的传质性能和驱油能力进行了评价。实验结果表明,最优泡沫体系配方为起泡剂w(AM-YY)=0.5%+起泡剂w(S-AN)=0.5%+稳泡剂w(WP3)=0.1%(ASW泡沫体系),在温度为80℃、矿化度为21315 mg/L的条件下该体系起泡体积为500 mL,析液半衰期可达22.4 min,电镜扫描结果显示ASW泡沫优化体系较常规体系生成的泡沫更加细小,并会在液膜形成致密的多层次网络结构;长填砂管实验表明优选泡沫体系的深部运移和封堵能力都明显优于常规泡沫体系;宏观驱油实验表明体系提高采收率幅度为31%,较常规泡沫体系提高11%。

Aiming at problem of poor stability and limited profile control ability of conventional foam system,a foam plugging system suitable for in-situ gas generating technology was selected by Waring Blender method.Mass transfer performance and oil displacement ability of the optimized system were evaluated by long sand-filled tube test and micro-flooding test.Experimental results showed that the optimal formula was 0.5%AM-YY+0.5%S-AN+0.1%WP3(ASW).Foaming volume of the system was 500 mL and half-life of the solution was up to 22.4 min when temperature was 80℃and salinity was 21315 mg/L.SEM result showed that the foam formed by the optimized system was smaller than that of conventional system and formed a dense multilayer network structure on the liquid film.Long sand filled tube test showed that deep migration and plugging ability of optimized foam system were obviously better than those of conventional foam system.The microscopic oil displacement test showed that EOR of the optimized system was 31%,which was 11%higher than that of the conventional system.