BASIC ENHANCED OIL RECOVERY : SCREENING CRITERIA AND SELECTION OF MOST APPROPRIATE EOR METHOD EOR

BASIC ENHANCED OIL RECOVERY : SCREENING CRITERIA AND SELECTION OF MOST APPROPRIATE EOR METHOD

EOR (Enhanced Oil Recovery) refers to the recovery of oil that is left behind after primary and secondary recovery methods are either exhausted or no longer economical. Primary production is the first oil out.  In Primary Recovery, oil is forced out by pressure generated from gas present in the oil. Secondary recovery methods are used when there is insufficient underground pressure to move the remaining oil. The most common technique is water flooding.

EOR (Enhanced Oil Recovery)  is an oil recovery enhancement method using sophisticated techniques that alter the original properties of oil. In other words, EOR (Enhanced Oil Recovery)  is a generic term for techniques for increasing the amount of crude oil that can be extracted from an oil field. By using EOR, 30-60%, or more, of the reservoir's original oil can be extracted compared with 20-40% using primary and secondary recovery.

EOR (Enhanced Oil Recovery) is  also known as improved oil recovery (IOR) or tertiary recovery (as opposed to primary and secondary recovery). There are  three major types of enhanced oil recovery operations. They are chemical flooding (alkaline – surfactant – polymer (ASP) flooding or surfactant – polymer (SP) flooding or polymer flooding), miscible displacement (carbon dioxide [CO2] injection or hydrocarbon injection), and thermal recovery (steam flooding or in-situ combustion). Over the years, a number of other innovative EOR (Enhanced Oil Recovery) processes have been conceived, including injection of carbonated water, microorganisms, foams, alkaline (without surfactant), and other formulations.

A re-emerging EOR approach, microbial enhanced oil recovery (MEOR), is the use of microorganisms to generate chemicals (surfactants, polymers, etc.). MEOR relies either on injecting bacteria strands together with nutrients or on injecting nutrients to stimulate growth of bacteria naturally present in the formation. The specific surfactant- and polymer-generation process depends strongly on the type of microorganism and rock and fluid properties.

Each type of EOR (Enhanced Oil Recovery) can be optimally applied, depending on reservoir temperature, pressure, depth, netpay, permeability, residual oil and water saturations, porosity and fluid properties such as oil API gravity and viscosity.

Outline :

1.    Introduction to EOR methods

2.    Factors affecting oil recovery

3.    Reservoir life cycle and recovery process

4.    Enhanced versus improved oil recovery

5.    Life under primary recovery phase: Recovery targets and ways to improve

6.    Comparative performance of different EOR methods (miscible, thermal, chemical)

7.    Life under secondary recovery phases: Immiscible gas injection, waterflooding, recovery targets, ways to improve

8.    Life under enhanced oil recovery phase: Increasing complexity, cost/benefit consideration

9.    Miscible methods: Selection criteria, recovery targets and why they are seldom met; design considerations

10.  Chemical methods: Selection criteria, recovery targets and why they are seldom met, design considerations

11.  Thermal methods: Selection criteria, recovery targets and why they are seldom met, design considerations

12.  Screening criteria and selection of most appropriate EOR method

Participants :

This course may interest new recruits as  Engineers, geoscientists, management personnel or other technical personnel  with some experience in reservoir engineering. Benefits individuals who are responsible for the design, implementation, and management of EOR projects. Also beneficial for other technical personnel involved in numerical simulation studies, screening, and planning of EOR applications.