低炭素社会に向けた国内タイトオイル開発の展望

抄録

Four potential techniques contributing to low carbon society are discussed in the future view of domestic tight oil development for Onnagwa formation mainly distributed in Akita prefecture, Northern Japan. The first one is a new acid stimulation for aiming dissolution of minerals along veins extended into Onnagawa formation. The acid stimulation can be done with no extra pump power resulting in low energy consumption due to its stimulation mechanism relying on rock-acid interaction in a geochemical process. It might become a low carbon-emission technique. The second one is slim-hole drilling. The slim-hole drilling has been already reported as one of proved approaches to reduce drilling costs for North America shale development. Reducing hole size inherently means reducing input energy to remove rock mass in the subsurface and saving completion materials such as cement and steel. The slim-hole drilling in conjunction with the new acid stimulation should play an important role for Onnagawa tight oil development amid the trend of low carbon society. The rest techniques comprised of compressed natural gas transportation and CO₂EOR with direct air capture process are reviewed in the current status regarding technical readiness levels. It is believed that these techniques will contribute for progressing to low carbon society.