Field Test and History Matching of the CO₂ Sequestration Project in Coal Seams in Japan

抄録

Global warming is one of the most important environmental problems facing the world and considered to be caused by an atmospheric greenhouse effect. The contribution of CO₂ to this greenhouse effect is estimated to equate approximately 50% of the effect of all greenhouse gases together, therefore the reduction of CO₂ emission is becoming extremely important. One of innovative technologies for CO₂ reduction in the atmosphere is CO₂ sequestration. In Japan, a six-years project on CO₂ sequestration in Japanese coal seams was started in 2002. This project involves several R&D items including a field test. A micro pilot test has been conducted in the Ishikari coal field since 2003. CO₂ was actually injected into coal seam in 2004 for the first time in Japan. A larger volume of CO₂ was injected in 2005. This paper investigates these field tests and discusses important results obtained through the history matching of these CO₂ sequestration field tests. It is concluded that CO₂ was sequestrated in coal seams and at the same time, the recovery of coalbed methane was enhanced.