A Missouri University of Science and Technology researcher is working on a method to increase oil production and store carbon dioxide into oil formations — at the same time.
Dr. Baojun Bai, the Lester Birbeck Endowed professor of geosciences and geological and petroleum engineering at Missouri S&T, has received a U.S. Department of Energy grant to make the process of drawing oil from underground and storing CO2 more efficient using thermostable particle gels, which can resist the high temperature of formations.
Typically, water is used to flood an oil well formation to aid in oil recovery. But this method often leaves as much as two-thirds of the oil in a formation behind. Using carbon dioxide (CO2) for enhanced oil recovery is more efficient because CO2 can dissolve into oil, reducing oil viscosity. Currently about 5 percent of the United States’ oil production relies on CO2 flooding — but using CO2 comes with problems.
Formations are not uniform. Areas and layers allowing oil to pass through easily (high permeability) are interspersed with areas and layers where oil passes through less easily (low permeability). Injected CO2 flows through areas of high permeablity but leaves a lot of oil unswept in areas of low permeablity, Bai says. The differences in viscosity between the injected CO2 and oil can cause the CO2 to seep through fingers-like channels in the formation; the carbon dioxide that’s produced reduces the efficiency of the greenhouse gas storage in formations.
Reviewed 2015-09-03