A Simulation Study of Simultaneous Acid Gas EOR and CO2 Storage at Apaches Zama F Pool
The Plains CO2 Reduction (PCOR) Partnership is working with Apache Canada Ltd. (Apache) to validate the stored amount of CO2 during ongoing enhanced oil recovery (EOR) operation at the F pool of the Zama oil field situated in northwestern Alberta, Canada. Apache is capturing CO2 and H2S from a nearby gas-processing plant and injecting this stream into the F pool for simultaneous EOR and CO2 storage. Acid gas injection was initiated in December 2006 and is continuing to date. The present compositional flow simulation study aims to evaluate ways for maximizing ncremental oil recovery and CO2 storage capacity in this depleted and closed pinnacle reef structure. Two different versions (Version 1 and Version 2) of a constructed static geologic model were used for performing dynamic simulations. In the first simulation scenario that used, the Version 1 static model, additional storage capacity gain by pressure management through water extraction (no oil production) from the water zone below the oilwater contact (OWC) was investigated. The results clearly indicate the viability of formation water extraction for increasing storage capacity in a closed geologic structure. The second iteration of the constructed static geologic model (Version 2) was chosen for simulating cases of continuing the current EOR scheme with and without a bottom water extraction well. A fivefold (0.30 million metric tonnes [MMt] to 1.22 MMt) increase in CO2 storage capacity was observed with a bottom water extraction well compared to the case with no bottom water extraction well. This scheme also results in an incremental EOR recovery of 22.1% in the next 20 years, which is 5% more compared to the case of the existing EOR scheme (no bottom water extraction well). With over 700 pinnacle reef structures (oil-bearing or water-bearing) in the Zama subbasin, a careful selection of pinnacle structures similar to the F pool may provide significant storage capacity gain through water extraction from the underlying water zone (aquifer) while achieving a significant increase in oil recovery.View/Download Document
Event/Meeting Information
11th International Conference on Greenhouse Gas Control Technologies
11/18/2012
Kyoto,