**Author details**

*Enhanced Oil Recovery Processes - New Technologies*

the period of 30 years on Bakken Field:

puff process.

**6.3 Heavy oil reservoir**

ies are summarized in **Table 2**.

Development of CO2-EOR techniques for unlocking resources

Tight formation characterization and multistage fracturing

Unlocking Bakken potential through CO2 huff and puff

Optimum CO2 and water-based oil recovery processes for Bakken

in tight oil formations

optimization

formations

**Strategies Actions**

corresponding to three cycles in this case study.

much favorable for the CO2 huff and puff process.

The followings outcomes were observed during the simulation of CO2-EOR for

1.Oil recovery factor increases with the increasing number of cycles of CO2 huff and puff, and the incremental oil recovery factor at a 30-year period is 2.43%

2.Lower permeability, longer fracture half-length, and more heterogeneity are

mechanism for the reservoir with lower permeability during the CO2 huff and

Some of the world's largest reserves are heavy oil reservoirs. With oil in place equal to the largest conventional oil fields in the Middle East, these large reserves are found in more than thirty countries around the globe, but few of these deposits have been developed extensively. One of the problems in the heavy oil reservoir is asphaltenic oil precipitate in the reservoir. Asphaltene is a component in petroleum, especially heavy oils. The asphaltene content could be defined by its solubility. Basically, any component that dissolves in toluene and precipitates in alkane is considered as asphaltene [65]. Various strategies and possible action to oil recover-

Overall, heavy oil reservoirs are considered not favorable for CO2 flooding compared to light oil reservoir due to lack of sweep efficiency. The considerable viscosity difference between heavy oil and the injected CO2 results in poor sweep efficiency from heavy oil reservoirs. Moreover, there is a possibility of asphaltene precipitation during miscible displacement; therefore, the compatibility of fluids is an important

> • CO2 injection may be the most suitable technique for recovery. • Develop pragmatic and sustainable techniques in order to unlock

• For tight formations, the fracture systems are required such

• The results can be used to optimize the well spacing and fractur-

• Potential to use mixtures such as CO2/field gas, CO2/methane, or CO2/propane to improve the oil recovery under different

• To examine the oil recovery mechanisms and to evaluate the overall performance of WAG, GAW, and SWAG processes, in comparison to CO2 flooding under miscible conditions. • Aim to determine the proper timing and also the slug sizes for different CO2 and water-based oil recovery processes, including

resources in tight oil formations via this injection.

natural and hydraulic fracture.

• Efficient in fractured reservoirs.

their effects on total oil recovery.

ing strategies.

conditions.

*Strategies and action that could efficiently lead to increase in the recovery.*

parameter to consider when designing EOR process for heavy oil reservoirs.

3.The CO2 diffusion mechanism is more pronounced than the convention

**142**

**Table 2.**

Erfan Mohammadian1 \*, Badrul Mohamed Jan<sup>2</sup> , Amin Azdarpour3 , Hossein Hamidi4 , Nur Hidayati Binti Othman1 , Aqilah Dollah1 , Siti Nurliyana Binti Che Mohamed Hussein1 and Rozana Azrina Binti Sazali1

1 Faculty of Chemical Engineering, Universiti Teknologi Mara (UiTM), Shah Alam, Malaysia

2 Department of Chemical Engineering, University of Malaya, Kuala Lumpur, Malaysia

3 Department of Petroleum Engineering, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran

4 School of Engineering, King's College, University of Aberdeen, Aberdeen, UK

\*Address all correspondence to: erfan.723@gmail.com

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
