Iran has raised its in-place oil reserves by 2.5 billion barrels, employing enhanced oil recovery techniques, the head of reserves evaluation bureau at National Iranian South Oil Company announced on Tuesday.
Ramin Roqanian also told Shana that 43 studies, including simulation and reservoirs engineering research, have been conducted.
“The surveys not only has improved the management of these fields, but also resulted in a rise of 2.5 billion barrels of in-place recoverable oil reserves,” he said.
Iran’s proven oil reserves amount to over 150 billion barrels.
Likewise, the Persian Gulf country is one of the richest countries in terms of gas reserves.
Iran (34 trillion cubic meters) and Russia (32.6 tcm) hold the largest proven gas reserves, according to BP Statistical Review of World Energy 2015. But the US Energy Information Association places Russia ahead of Iran with an estimated 49 tcm in reserves.
Iran, Russia and Qatar together hold nearly half the world's proven gas reserves.
Roqanian noted that oil reservoirs with relatively large gas caps, newly developed and undeveloped reservoirs account for 13% of southern oilfields, on which comprehensive viability studies are being carried out.
The official noted that gas injection, as an enhanced oil recovery method, is not prescribed for all oilfields, but in accordance with a reservoir’s features, a suitable method should be employed.
Gas injection is presently the most commonly used method in enhanced oil recovery, accounting for nearly 60% of EOR production in the United States. The technique maintains reservoir pressure and improves oil displacement because the interfacial tension between oil and water is reduced.
“The development plan of each oilfield has been prepared as per its unique challenges. For instance, some of the fields require drilling new wells or other well activities such as hydraulic fracturing—breaking a rock by a pressurized liquid,” Roqanian explained.
"Other oilfields may need gas lift systems like well pumps, which are being implemented in some of the fields."
According to Roqanian, installation of the pumps can increase oil extraction by 3-4%.
