ABSTRACT: Reduction of "greenhouse gas" emissions through underground CO2 sequestration in Texas oil and gas reservoirs
Holtz, Mark H.1, David L. Carr2, and Peter K. Nance1
(1) Teknecon Energy Risk Advisors LLC, Austin, TX
(2) Geoscience Consultant, Austin, TX
A promising method for reducing CO2 emissions -- and thus reducing potential human impacts on global climate -- is through sequestration of CO2 in subsurface reservoirs. The greatest concerns regarding the feasibility of subsurface CO2 sequestration are the economics and the long-term trapping capability of a given reservoir over geologic time. Using CO2 emissions in enhanced oil recovery (EOR) operations may provide a solution that addresses both concerns. Oil reservoirs are ideal candidates for CO2 sequestration because they are proven geologic traps. Structural analysis, caprock evaluation, and pressure monitoring similar to the methods widely used by operators of underground gas-storage reservoirs can be applied to oil reservoirs to determine their viability for CO2 sequestration. The economic benefit from increased oil production resulting from EOR by CO2-injection would partly, or in some cases, fully offset the costs of power-plant CO2 capture, pipelines, and transportation. CO2 EOR can produce oil that would otherwise not be recovered, at an incremental cost of $6 to $12 per stock tank barrel (STB; 1992 U.S. dollars). More than 1,700 oil reservoirs are possible candidates for CO2 EOR in Texas. These reservoirs represent 80 billion STB of original oil in place, of which 31 billion STB is residual oil, the target for CO2 EOR. Eight (8) billion STB of this resource is within a 90 mile radius of candidate coal or lignite fired plants in Texas. In addition, between twelve (12) and twenty (20) years of CO2 production from nineteen (19) lignite or coal fired boilers could be sequestered.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia