Recovery rates, enhanced oil recovery and technological limits

Abstract

Enhanced oil recovery (EOR) techniques can significantly extend global oil reserves once oil prices are high enough to make these techniques economic. Given a broad consensus that we have entered a period of supply constraints, operators can at last plan on the assumption that the oil price is likely to remain relatively high. This, coupled with the realization that new giant fields are becoming increasingly difficult to find, is creating the conditions for extensive deployment of EOR. This paper provides a comprehensive overview of the nature, status and prospects for EOR technologies. It explains why the average oil recovery factor worldwide is only between 20% and 40%, describes the factors that contribute to these low recoveries and indicates which of those factors EOR techniques can affect. The paper then summarizes the breadth of EOR processes, the history of their application and their current status. It introduces two new EOR technologies that are beginning to be deployed and which look set to enter mainstream application. Examples of existing EOR projects in the mature oil province of the North Sea are discussed. It concludes by summarizing the future opportunities for the development and deployment of EOR.

Decline and depletion rates of oil production: a comprehensive investigation

“…(iii) Tertiary (enhanced) oil recovery Tertiary recovery or enhanced oil recovery (EOR) involves more complex ways of influencing rock and fluid properties [20]. The feasibility of EOR, together with the appropriate approach to EOR, will vary with the fluid properties and geological characteristics of the reservoir.…”

The future of oil supply

“…In the first, Muggeridge et al [6] provide a comprehensive overview of the nature, status and prospects for EOR techniques and their potential contribution to global oil supply. They begin by introducing the oil field recovery equation, summarizing the evidence on global recovery rates and explaining why these are typically low.…”

“…Future global production is therefore heavily dependent on the future prospects of the giant fields, but this remains uncertain-in part because the required field-level data are either unavailable or unreliable [4]. 6 …”

“…Falling pressure reduces the flow rate and may also permit gas to exsolve from the oil. On average around 35% of the original oil in place can be recovered by these methods [5][6][7]. Wells become uneconomic when the oil flow rate becomes too low, particularly when large volumes of water from secondary recovery are co-produced.…”

Nanoparticle-Assisted Water-Flooding in Berea Sandstones

“…The era of finding "easy oil" is coming to an end, and future supply will become more reliant on fossil fuels produced from non-conventional reservoirs and from enhanced oil recovery (EOR) processes. It is estimated that the average oil recovery rate from mature oilfields around the world is typically 20%-40% of the original oil in place (OOIP) 1 , which leaves enormous potential for developing efficient EOR technologies. Among various secondary or tertiary recovery techniques, water injection is the most-widely used.…”