三次采油用小分子自组装超分子体系驱油性能

Study on oil displacement performance of self-assembled small-molecule supramolecular system for EOR

胜利油区三类油藏由于温度和矿化度较高,常规聚丙烯酰胺驱油剂无法在该类油藏条件下取得较好的驱油效果。为此,利用自制的超分子主剂和辅剂,研制耐温抗盐非聚丙烯酰胺类新型超分子体系,并对其基本性能、驱油效果及微观聚集形态进行分析。研究结果表明:超分子体系利用小分子之间的自组装,能够形成和常规聚丙烯酰胺一样致密的网络聚集体;在胜利油区三类油藏条件下,超分子体系质量分数为0.1%~0.25%时相对于常规聚丙烯酰胺,粘度提高1倍以上;不除氧条件下,超分子体系在30 d内粘度保持稳定;超分子体系质量分数为0.15%时的单管物理模拟实验能提高采收率18%以上;因此,超分子体系是一种非常有前景且能适用于胜利油区高温高盐油藏的新型驱油体系。

Due to high temperature and high salinity in type-Ⅲreservoirs of Shengli oilfield,conventional polyacrylamide oil displacement agent cannot effectively enhance oil recovery. Therefore,a new type of non polyacrylamide supramolecular system with temperature resistance and salt tolerance was developed with self-made supramolecular main agent and assistant agent. And the basic performance,oil displacement efficiency and microscopic accumulation morphology were characterized. The result shows that the supramolecular system can form dense network aggregate like HPAM by self-assembly between small molecules. Under the condition of type-Ⅲreservoirs in Shengli oilfield,the viscosity of the supramolecular system increases by more than one time with mass concentration of 0.1%-0.25% compared with HPAM. Without oxygen removal,the viscosity of the supramolecular system keeps stable within 30 days. Single pipe physical simulation may enhance oil recovery by over 18% when the mass concentration of supramolecular system is 0.15%. So the supramolecular system is a very promising new type of oil displacement,suitable for high temperature and high salinity reservoirs in Shengli oilfield.