The majority of daily oil production in today’s market comes from mature or maturing fields. New discoveries of recoverable reserves are failing to match the pace set by the growing global demand for energy.

This, in turn, increases the requirement for new technologies that can enhance recovery from both active fields and future discoveries.

The hydrocarbon resources found within carbonate reservoirs are in particular need of innovative new technologies to facilitate their economic exploitation. Carbonates are of critical importance to the oil and gas industry, with more than 60% of the world’s oil and 40% of its gas reserves trapped in such carbonates. Despite this, recovery factors using primary, secondary and tertiary methods from carbonates are significantly lower than that of sandstones.

The high oil price period of recent years resulted in both an increased interest in EOR R&D and a willing-ness to invest substantially in a wide range of techniques and approaches. There is concern that this enthusiasm is now diminishing due to last year’s fall in the oil price and its sustained lower level at the current time, with companies sticking to the less-costly tried and tested waterflooding technique as the preferred method of enhancing oil production.

Middle East drive
Carbonate fields dominate the Middle East region, with approximately 70% of oil and 90% of gas reserves held within carbonate reservoirs. The upstream industry in this region is, however, still reasonably buoyant compared to elsewhere in the world, despite the slump in the oil price. In addition, companies are continuing to invest in developing potential fields while other regions have and still are cutting back.

The Industry Technology Facilitator (ITF)’s Middle East-based members in particular are showing significant appetite for developing new technologies that can help them maximize their returns from carbonates. The organization’s EOR/carbonates workshop in Kuwait in January 2015 was the first such initiative and focused solely on its Gulf Cooperation Council (GCC) members. These include major players such as Petroleum Development Oman (PDO), Qatar Petroleum, Kuwait Oil Co.
and ADMA-OPCO.

ITF has been active in the Middle East for a number of years and has done a great deal of work to build up trust, promoting and spearheading collaborative activity in the region. The workshop was the first time member companies had collectively shared ideas and, following discussions with world-leading experts and academics, the group agreed on three main EOR techniques in carbonate reservoirs for further development:
• Low salinity;
• Miscible and near-miscible gas injection; and
• Foam flooding.

EOR remains high on the agenda for operators in the Middle East given the large amount of onshore reserves contained in the region, with the expectation that much more can be extracted by improving the extraction rate. The costs are relatively low in comparison to the North Sea, for example, with the complications that come with working offshore.


EOR methods
Currently there are several methods that are most commonly used in increasing and/or enhancing oil recovery, including CO2 injection, steam injection, waterflood injection and reservoir stimulation.

There have been successful deployments of some of these methods in carbonates, but there remains much room for improvement. This presents an opportunity for the development of advanced secondary and tertiary technologies that may mitigate the current low recovery rates from carbonates as well as enhance current recovery rates from sandstone reservoirs.


Principally, the factors behind the low recovery rates in carbonates are low wettability, natural fractures, and highly
heterogeneous and seemingly unpredictable static and dynamic reservoir properties. Hence, further research is necessary to improve understanding of these factors and their impact on various EOR techniques.

Stepping stone

A drive toward low-salinity injection, miscible and nearmiscible gas injection, foam flooding, and nano-surfactant enhancement technologies could prove to be a vital stepping stone in improving recovery from carbonates.

In maturing basins worldwide any such improvement in recovery rates could prove to be the vital boost needed in order for them to remain economically viable and to ensure that future issues of supply and demand are better managed and controlled.

Studies estimate that a mere 1% increase in the global efficiency of hydrocarbon recovery could raise conventional oil reserves by up to 88 Bbbl, the equivalent of three years of annual production at today’s levels.

Collaboration

ITF’s role in the Middle East is evolving from initially instigating collaborative ventures into facilitating project work and technology development.

U.S.-based ProSep, for example, last December launched a 12-month joint industry project (JIP) with Qatar Petroleum and PDO, with the contractor and the two national oil companies (NOCs) collaborating on an offshore-capable unit for oil-in-water removal and media regeneration. This project marked the first truly collaborative ITF-sponsored JIP between two NOCs in the region.

By working with its GCC members, ITF is looking to develop a collaborative technology roadmap that has been pivotal in bringing the Middle Eastern companies together to share ideas. The results of the workshop earlier this year suggested that there were two further areas of interest—not only EOR but also the reduction of the environmental impact of the activities of the oil and gas industry.

ITF is working with its Middle East members to collaborate with developers on innovative projects. One such project is Cyclone, an initiative centered on real-time production logging, while another is the Imperial College London’s Waterfront Imaging Using Self-Potential, which could allow imaging of waterfronts several tens to hundreds of meters away from an instrumented well. Both of these could initiate a new approach among the GCC members.

The vision for ITF is to see local collaboration tapped into a global agenda as has been achieved by the organization in Brazil, which has a similar interest to the Middle East in carbonate reservoirs.

Recovery rise of 30% to 60%
The overall contribution from EOR techniques has remained relatively stagnant over the long-term at around 3.5% of daily global production, and it is primarily used to target immobile oil that cannot be produced from primary and secondary methods.

Commonly, an increase in production of between 30% and 60% of a reservoir’s original oil-in-place is expected, with the global average recovery rate from hydrocarbons currently somewhere around the mid-30s percentage range.

This emphasizes the need for new technologies capable of increasing recovery trends in oil production, particularly for carbonates. If the large quantities of resources found within these reservoirs can be exploited to a similar level as clastic reservoirs currently exploited by EOR techniques, it may go some way toward alleviating the plethora of issues related to rising global energy demand.

Comments