Lai Nanjun, Zhu Qingru, Qiao Dongyu, Chen Ke, Wang Dongdong, Tang Lei, Chen Gang
School of Chemistry and Chemical Engineering of Southwest Petroleum University, Chengdu, China.
State Key Laboratory of Oil and Gas Geology and Exploitation of Chengdu University of Technology, Chengdu, China.
Front Chem. 2020 May 21;8:393. doi: 10.3389/fchem.2020.00393. eCollection 2020.
During CO flooding, serious gas channeling occurs in ultra-low permeability reservoirs due to the high mobility of CO. The chief end of this work was to research the application of responsive nanoparticles for mobility control to enhance oil recovery. Responsive nanoparticles were developed based on the modification of nano-silica (SiO) by 3-aminopropyltrimethoxysilane (KH540) via the Eschweiler-Clark reaction. The proof of concept for responsive nanoparticles was investigated by FT-IR, H-NMR, TEM, DLS, CO/N response, wettability, plugging performance, and core flooding experiments. The results indicated that responsive nanoparticles exhibited a good response to control nanoparticle dispersity due to electrostatic interaction. Subsequently, responsive nanoparticles showed a better plugging capacity of 93.3% to control CO mobility, and more than 26% of the original oil was recovered. Moreover, the proposed responsive nanoparticles could revert oil-wet surfaces to water-wet, depending on surface adsorption to remove the oil from the surface of the rocks. The results of this work indicated that responsive nanoparticles might have potential applications for improved oil recovery in ultra-low permeability reservoirs.
在CO驱油过程中，由于CO的高流动性，超低渗透油藏会出现严重的气窜现象。这项工作的主要目的是研究响应性纳米颗粒在控制流度以提高采收率方面的应用。通过埃施魏勒-克拉克反应，用3-氨丙基三甲氧基硅烷（KH540）对纳米二氧化硅（SiO）进行改性，制备了响应性纳米颗粒。通过傅里叶变换红外光谱（FT-IR）、氢核磁共振（H-NMR）、透射电子显微镜（TEM）、动态光散射（DLS）、CO/N响应、润湿性、封堵性能和岩心驱替实验，对响应性纳米颗粒的概念进行了验证。结果表明，响应性纳米颗粒由于静电相互作用，在控制纳米颗粒分散性方面表现出良好的响应。随后，响应性纳米颗粒对CO流度的控制封堵能力达到93.3%，原油采收率提高了26%以上。此外，所提出的响应性纳米颗粒可以根据表面吸附作用将油湿表面转变为水湿表面，从而从岩石表面去除原油。这项工作的结果表明，响应性纳米颗粒在提高超低渗透油藏采收率方面可能具有潜在应用。
