A comprehensive review of the chemical-based conformance control methods in oil reservoirs

Abstract

The production of excess water during oil recovery creates not only a major technical problem but also an environmental and cost impact. This increasing problem has forced oil companies to reconsider methods that promote an increase in oil recovery and a decrease in water production. Many techniques have been applied over the years to reduce water cut, with the application of chemicals being one of them. Chemicals such as polymer gels have been widely and successfully implemented in several oil fields for conformance control. In recent years, the application of foam and emulsions for enhanced oil recovery projects has been investigated and implemented in oil fields, but studies have shown that they can equally act as conformance control agents with very promising results. In this paper, we present a comprehensive review of the application of polymer gel, foam and emulsion for conformance control. Various aspects of these chemical-based conformance control methods such as the mechanisms, properties, applications, experimental and numerical studies and the parameters that affect the successful field application of these methods have been discussed in this paper. Including the recent advances in chemical-based conformance control agents has also been highlighted in this paper.

A Novel Numerical Model of Gelant Inaccessible Pore Volume for In Situ Gel Treatment

“…Reservoir heterogeneity is one reason for low oil recovery and early excessive water production. To reduce excessive water production and to improve sweep efficiency, many technologies, including polymer flooding and foam flooding, have been widely applied over the past several decades [ 1 ]. One of the most popular treatment methods is to inject gels to reduce the flow capacity of channels or fractures and divert the following fluid (i.e., water) to un-swept oil zones [ 2 , 3 , 4 , 5 , 6 ].…”

Technical Evaluation of Conformance Improvement Technology with Anionic Surfactant-Stabilized Microemulsions in Porous Media

“…The research sector is engaged in the development of efficient, economical conformance solutions to meet the ever-increasing oil and gas requirements on a global scale. This has led to focusing our research goals toward the attainment of two typical features of interest: decline of water production and diversion of flow transport towards "hard-to-produce" zones (Alhuraishawy et al, 2019;Lakatos and Lakatos-Szabó, 2012;Sagbana and Abushaikha, 2021). The existence of high permeability streaks, faults, fractures, and thief zones gives rise to conformance problems, wherein oil remains trapped within low permeability zones and a significant water-cut issue occurs in the reservoir (Sagbana and Abushaikha, 2021;Seright and Brattekas, 2021;Yu et al, 2018).…”

“…This has led to focusing our research goals toward the attainment of two typical features of interest: decline of water production and diversion of flow transport towards "hard-to-produce" zones (Alhuraishawy et al, 2019;Lakatos and Lakatos-Szabó, 2012;Sagbana and Abushaikha, 2021). The existence of high permeability streaks, faults, fractures, and thief zones gives rise to conformance problems, wherein oil remains trapped within low permeability zones and a significant water-cut issue occurs in the reservoir (Sagbana and Abushaikha, 2021;Seright and Brattekas, 2021;Yu et al, 2018). These regions act as favorable conduits for injected fluids, thereby causing several low-permeability oil zones to remain unexplored (Abdulbaki et al, 2014;Imqam et al, 2017Imqam et al, , 2015.…”

“…Conventional chemicals such as polymers and gels have been widely used in field conditions to create a beneficial 'conforming drive' within the pores (Al-Ali et al, 2013;Li et al, 2020;Pinho De Aguiar et al, 2020;Sagbana and Abushaikha, 2021). However, polymers/gels are associated with problems such as instability, low salt tolerance, and degradation that make them unsuitable for application in long-term scenarios (Dai et al, 2014;Fathima et al, 2019;JOUENNE, 2020;Kang et al, 2021).…”

“…Microemulsion-assisted conformance improvement technology (ME-CIT) is based on the cyclic injection of microemulsion/surfactant slugs in surface conditions and sufficient viscosity within the targeted pore regions (Das et al, 2020;Quintero et al, 2015;. It relies on two important attributes: stability and viscosity (Divandari et al, 2021;Sagbana and Abushaikha, 2021;X. Zhou et al, 2020).…”