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Summary

Carbon capture and storage (CCS) is one of the most important emission-reduction technologies available for large stationary CO₂ sources. Fossil-fueled power generation is the largest source of carbon dioxide (CO₂) that could be captured and stored. Depleted oil and gas fields and major CO₂ sources nearby are ideal places for large-scale geological storage. Injection of CO₂ into a depleted reservoir can enhance the recovery of hydrocarbons. The circumstances, in fact, dictate that the CO₂ enhanced-oil-recovery (EOR) industry and power-generation sector should be eager to magnify the mutually beneficial link between CO₂ EOR and new industrial sources of CO₂.

In 1986, the Turkish Petroleum Corporation (TPAO) started the first large-scale immiscible-CO₂-injection project in southeastern Turkey. Approximately 1 million tons/yr of naturally occurring CO₂ has been injected into Garzan carbonates in the Bati Raman field. A substantial increase in the production rate and ultimate recovery has been experienced, and this is expected to continue. The Bati Raman immiscible-CO₂-injection project has been acknowledged as one of the most unique and successful EOR applications in the history of heavy oil in fractured-limestone reservoirs.

There are nearly 50 oil fields in Turkey, and a significant proportion of them would be potentially suitable for EOR. If sufficient volumes of CO₂ were economically available, many of these could produce incremental oil for an extended period. It is a fact that sedimentary basins in the Middle East are typically carbonates, and this limits the selection of EOR processes significantly. Having observed CO₂ injection as an excellent choice for carbonates through experience with the Bati Raman field, one may extend the CO₂ network idea to the whole region. This will not only activate the enormous EOR potential in the mature fields of the Middle East, but also the permanent storage of CO₂ through a common effort.

The use of captured CO₂ for EOR will become feasible if CO₂-recovery plants with a higher CO₂ content give an attractive CO₂ delivery cost and emission rights can be traded in the carbon market, which was introduced by the Kyoto protocol. The major challenges would be formulating a working and acceptable model between petroleum and power sectors and to establish a market mechanism to ensure that this system becomes economically feasible.