Improvement of Environmental Monitoring Technology on the basis of Carbon Mass Balance during CO2-enhanced Oil Recovery and Storage

AbstractThis study reviewed the emission inventory of carbon injection, production, storage, and emission. Results indicated that only approximately 95% of injected CO2 can be measured. Approximately 92% to 95% of carbon was stored, 0.01% was leaked from soil, and the residual 5% may have come from leak paths or may have leaked from near-surface sources, such as underground water, through biological metabolism. To develop a carbon mass balance model for CO2 enhanced oil recovery projects, the emission part from soil and underground water, as well as the fixation by vegetation, should be carefully measured. The residual 5% that remains unmeasured should be proven, i.e., whether such amount is derived along leak paths or is emitted from near-surface sources. Findings could highlight the fate of carbon, provide some suggestions to guide the selection of environmental monitoring technology, and aid in establishing a common methodology to identify leak risks for carbon storage projects