Currently the daily oil production comes from mature or maturing oil fields and reserves replacement is not keeping pace with the growing energy demand. The world average recovery factor from hydrocarbon reservoirs are stuck in the mid-30 percent range. If the average world wide recovery factor from hydrocarbon reservoirs can be increased beyond current limits, it will alleviate a number of issues related to global energy supply, mitigating the demand-supply balance, which can be achieved by using improved oil recovery (IOR) and enhanced oil recovery (EOR)
Primary and secondary recovery (conventional recovery) targets mobile oil in the reservoir and tertiary recovery or EOR targets immobile oil (that oil which cannot be produced due to capillary and viscous forces).
The timing of EOR is important. A case is made that advanced secondary recovery (improved oil recovery or IOR) technologies are a better first option before full-field deployment of EOR. That is cause of the implementation of EOR is intimately tied to the price of oil and overall economics. EOR is capital and resource intensive, and expensive, primarily due to high injection cost.
Besides, the projects are generally complex, technology-heavy and require considerable capital investment and financial risks. The risks are aggravated with the fluctuations in the price of oil. The unit costs of EOR oil are substantially higher than those of secondary or conventional oil. Another challenge for EOR projects is the long lead time required for such projects. Typically, it may take several decades from the start of the concept – generating laboratory data and conducting simulation studies – to the first pilot and finally, full commercialization.
While there has been some discussion in the literature of applying or deploying EOR at an early stage of a reservoir’s life, this is generally difficult, and not necessarily the best option, due to the risks involved and lack of data availability, that can easily be obtained during the secondary stage of recovery.
So, why is there EOR if IOR is easier to be applied? This can be answered by table below:
Primary and secondary recovery (conventional recovery) targets mobile oil in the reservoir and tertiary recovery or EOR targets immobile oil (that oil which cannot be produced due to capillary and viscous forces).
The timing of EOR is important. A case is made that advanced secondary recovery (improved oil recovery or IOR) technologies are a better first option before full-field deployment of EOR. That is cause of the implementation of EOR is intimately tied to the price of oil and overall economics. EOR is capital and resource intensive, and expensive, primarily due to high injection cost.
Besides, the projects are generally complex, technology-heavy and require considerable capital investment and financial risks. The risks are aggravated with the fluctuations in the price of oil. The unit costs of EOR oil are substantially higher than those of secondary or conventional oil. Another challenge for EOR projects is the long lead time required for such projects. Typically, it may take several decades from the start of the concept – generating laboratory data and conducting simulation studies – to the first pilot and finally, full commercialization.
While there has been some discussion in the literature of applying or deploying EOR at an early stage of a reservoir’s life, this is generally difficult, and not necessarily the best option, due to the risks involved and lack of data availability, that can easily be obtained during the secondary stage of recovery.
So, why is there EOR if IOR is easier to be applied? This can be answered by table below:
From the tabel above, it can be seen that the EOR is used when the IOR was no longer able to add recovery from the reservoir. While using EOR, recovery can be boosted, up to 80 percent. EOR method chosen are depending on the physical condition of the reservoir, the availability of injectants and comprehensive total economic analysis.
Writer: Ranu Santoso Nugroho
Editor: Marthin SIburian
Writer: Ranu Santoso Nugroho
Editor: Marthin SIburian