论文部分内容阅读
针对国内老油田的开发现状,对设计的乳化剂配方体系进行了基本性能评价和乳化驱油效果研究,探讨了乳化驱油的可行性和驱油机理。研究结果表明,优选的乳化剂配方体系HC-5(氨基磺酸型两性活性剂20%,OP系列非离子表面活性剂8%,稳定剂0.8%,助溶剂2.5%,其余为水)具有良好的耐盐抗盐性能,在室温数85℃范围内、盐度超过120 g/L的混合盐水中的溶解性良好;HC-5能在高、中和低盐度的盐水中有效乳化原油,并具有良好的乳化稳定性;HC-5乳化体系的乳状液类型与盐度和含水率有关,盐度增加时,发生W/O型乳状液向O/W型转变的临界含水率增大,矿化度为15350 mg/L、40650 mg/L和120670 mg/L的体系的临界含水率分别为48%、57%和68%。室内模拟乳化驱油试验表明,乳化驱对于低渗透驱替介质有明显增压和调剖作用,波及系数增大,原油采收率提高;而对于较高渗透率的驱替介质,乳液的调剖机理和表面活性剂驱油机理共同作用实现了原油采收率的提高。
In view of the development status of the old oilfields in China, the performance evaluation of the emulsifier formulation system and the effect of emulsification and oil displacement were studied. The feasibility of emulsification and oil displacement and the oil displacement mechanism were discussed. The results show that the preferred emulsifier formulations HC-5 (sulfamic acid amphoteric active agent 20%, OP series nonionic surfactant 8%, stabilizer 0.8%, cosolvent 2.5%, the rest is water) has good Salt-tolerant and salt-tolerant, good solubility in mixed brine with salinity more than 120 g / L at room temperature 85 ℃; HC-5 can effectively emulsify crude oil in high, medium and low salinity brine, And has good emulsification stability. The type of emulsion of HC-5 emulsion system is related to salinity and water content. When the salinity increases, the critical moisture content of W / O emulsion to O / W transition increases, The critical moisture content of the systems with salinity 15350 mg / L, 40650 mg / L and 120670 mg / L were 48%, 57% and 68%, respectively. Laboratory simulation of emulsification and oil displacement tests showed that emulsification flooding had obvious pressurization and profile control effects on low-permeability displacements, and the sweep coefficient increased and the oil recovery rate increased. For the high-permeability displacing medium, the emulsion transfer Partition mechanism and surfactant flooding mechanism to achieve the effect of enhanced oil recovery.