改性纳米SiO_(2)流体提高采收率机理实验研究

Experimental Study on the Enhanced Oil Recovery Mechanism of Modified Nano-SiO_(2) Fluid

纳米流体具有表面效应、小尺度效应和量子效应,在油藏多孔介质中产生较强的化学驱油能力和物理剥离原油能力。低渗透油藏开发难度大,纳米驱油技术具有提高采收率的潜力,但是纳米流体驱油能力和渗流规律研究较少。研制了新型改性纳米SiO_(2)材料,通过扫描电镜和粒度测试分析其结构和物理特征;对比分析纳米流体和油田常用表活剂,纳米流体改善油水界面张力能力较强,能达到10^(-2)mN·m^(-1)水平;纳米流体可以显著提高岩心亲水性,渗吸液吸附前接触角为115.0°,吸附后接触角为26.9°;驱油能力实验表明,纳米流体能够有效增注和降低含水量,提高采收率达到20.28%。

Nanofluids have surface effects, small-scale effects and quantum effects, which produce strong chemical flooding ability and physical stripping ability in reservoir porous media. The development of low-permeability reservoirs is difficult, and nano-flooding technology has the potential to improve oil recovery, but there are few studies on the oil-flooding capacity and seepage law of nano-fluids. In this paper, a new type of nanomaterial was developed,and its structure and physical characteristics were analyzed by scanning electron microscopy and particle size test;the nanofluid and common surfactant used in oilfields were compared and analyzed, and the nanofluid improved the tension of the oil-water interface with a strong ability to reach the level of 10^(-2)mN·m^(-1) The nanofluid could significantly improve the hydrophilicity of the rock core, and the contact angle before adsorption of the seepage was 115.0°, and the contact angle after adsorption was 26.9°;The oil flooding ability experiment showed the nanofluid could effectively increase the injection amount and reduce the water content, and the recovery rate was increased by 20.28%.