低渗油藏缔合聚合物调剖体系

缔合聚合物调剖技术通过添加交联剂,使之与缔合聚合物形成三维网状结构体系,可控制成胶时间及强度,改善了单纯聚合物体系存在的抗盐性、耐温性、抗剪切性差的问题。针对马寨油田油藏特点,对缔合聚合物的黏-浓、黏-温、稳定性、耐盐性、耐剪切性等指标进行评价,试验结果表明,缔合聚合物体系具有良好的抗温、抗盐及剪切恢复性能。在95℃、马寨注入水配制条件下,3000mg/L时体系黏度可达64mPa·s;在同浓度下(1000mg/L),与聚丙烯酰胺、AMPS聚合物常温增黏特性相比,缔合聚合物黏度高于前二者2~30倍。现场实施取得了良好的增油效果,表明缔合聚合物调剖体系适用于低渗透油藏提高采收率的需要。

Profile Modification by Hydrophobic Associating Polymer System in Low Permeability Reservoir

Profile modification technology by hydrophobic associating polymer is to add crosslinker to polymer to compose three dimension structure by controlling the composed time and strength, which can improve the weakness of salt resistance, temperature endurance and shearing resistance existing in sole polymer system. According to Mazhai Oilfield’s specialties, through a series of parameter tests and evaluation to viscosity-density, viscosity-temperature, stability, salt and shearing resistance, it shows that the investigated Mazhai Oilfield’s hydrophobic associating polymer has the high characters of temperature endurance, salt resistance and shearing restress. In the condition of 95℃ and Mazhai injection water, the 3000 mg/L polymer viscosity is only 64 mPa.s. Compared with polyacrylamide and AMPS polymer, its viscosity can be up to hundreds times of them and higher. Site application has verified that it has the great potencies to increase the production, and shows that this system can fit for the use as to promote the production in low permeability oil field reservoirs.