Abstract

The carbon dioxide (CO₂) injection is the promising enhanced oil recovery technique used in low permeability reservoirs. The presence of high permeability fractures along the matrix leads to poor sweep efficiency and gas channeling effect. The CO₂ responsive mobility control gels could be a potential solution to mitigate the gas channeling effects. This work showcases the straightforward method to prepare a CO₂ responsive gel by mixing aqueous suspension of nanocellulose and ethylenediamine. The addition of CO₂ leads to protonation of amine which enhances the ionic strength of the solution. This promotes the agglomeration of nanocellulose to form gel. The rheological properties of the gel were studied and found to have interesting mechanical property. And the micromodel is used to visualize the mobility control phenomenon of the as prepared gel. The core flooding experiment proves that the synthesized gels were effective in low permeable cores.

摘要

二氧化碳（CO ₂）注入是用于低渗透油藏的有前景的提高采油技术。沿基质存在高渗透性裂缝导致波及效率和气道效应较差。CO ₂响应迁移率控制凝胶可能是减轻气体通道效应的潜在解决方案。这项工作展示了通过混合纳米纤维素和乙二胺的水悬浮液制备 CO ₂响应凝胶的简单方法。CO _{2 的添加}导致胺质子化，从而提高溶液的离子强度。这促进了纳米纤维素的团聚以形成凝胶。研究了凝胶的流变特性并发现其具有有趣的机械特性。并使用微模型来可视化所制备凝胶的流动性控制现象。岩心驱油实验证明合成的凝胶在低渗透岩心中是有效的。