Viscosity enhancement of CO2 by rod-like reversed micelles for enhanced oil recovery(Fostering Joint International Research)

2019 Fiscal Year Final Research Report

• Project/Area Number: 15KK0221
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Earth system and resources engineering
• Research Institution: Hirosaki University
• Principal Investigator: Sagisaka Masanobu 弘前大学, 理工学研究科, 准教授 (60374815)
• Project Period (FY): 2016 – 2019
• Keywords: 原油増進回収 / 二酸化炭素 / 界面活性剤 / 棒状 / 粘性 / 会合体 / 泡

Outline of Final Research Achievements

To increase a sweep efficiency in enhanced oil recovery using carbon dioxide, this study aimed to develop rod-like aggregates and foams in supercritical CO2 as a CO2-viscosifer. As the results, we found the fluorocarbon-hydrocarbon hybrid surfactant FC6-HC5 to form rod-like reverse micelles enable to increase CO2 viscosity by three times. On the other hand, this study successfully developed mixtures of CO2-philic polymers and fluorocarbon-hydrocarbon hybrid compounds having no headgroups to form rod-like aggregates active even at a high salinity condition in oil fields. The aggregates were suggested to thicken CO2 by two times. Foams were also generated in mixtures of supercritical CO2 and high salinity brines by using nonionic surfactants. These molecular assemblies were identified as one of the most efficient and effective CO2-viscosifers in earlier studies.

Free Research Field

コロイドおよび界面化学、超臨界流体工学

Academic Significance and Societal Importance of the Research Achievements

本研究成果は、日本が効果的なEOR技術を手にするおおきな一歩となり，他国の石油資源を採掘する権利を獲得するチャンスを増やす。そして，ガス攻法における原油回収率を2倍以上に増加させるものであり，回収されずに油田に残っている原油をより多く回収し，可採年数を増やす役割を果たす。この技術は，言い換えれば，新たな油田を発見するのと同等の価値をもち，この原油資源の延命措置が，非炭素エネルギー源に置き換わるまでに必要な時間を可能な限り多く稼ぐことである。また，本成果の分子集合体は、EORのみならず，微粒子合成，抽出，ドライクリーニング，乾式精密洗浄，染色，酵素反応などに有望な将来技術を与える。