Multifunctional Evaluation of a New Supramolecular Complex in Enhanced Oil Recovery, Removal/Control of Organic Damage, and Heavy Crude Oil Viscosity Reduction

Abstract

The development of new technologies based in the design and application of new molecules to solve problems related to the removal and control of formation damage by organic deposition, viscosity reduction of heavy crude oils as well as to increase the oil recovery factor, is an important challenge in the oil industry. This experimental study reports the influence of a novel supramolecular complex on the removal/control of organic deposition and Enhanced oil recovery (EOR) processes through core displacements tests at reservoir pressure and temperature conditions. In addition, its capabilities as viscosity reducer for heavy crude oils are also reported. Three different Mexican brine-rock-crude oil systems were used to evaluate the multifunctional properties of the novel supramolecular complex. Results showed a good performance of the capabilities of the supramolecular complex tested to reduce viscosity, remediate organic damage as well as to enhance oil recovery factor. In order to explain the results obtained, an interaction mechanism between the new complex and crude oil heavy fractions on the porous medium, is suggested and discussed, in which phenomena such as oildisaggregation, wettability-alteration and viscosity reduction, take place to carry out the increasing of oil recovery factor and an efficient removal of organic damage.

Application of Multifunctional Agents During Enhanced Oil Recovery

“…Supramolecular chemistry is based on the phenomenon of molecular recognition through weak forces between molecules, which promotes self-assembly [18]. This is a promising technology that has impacted the design of new materials with interesting applications in the chemical industry including the petroleum industry [7,19,20].…”

“…The deposition of organic components also renders rock wettability changes from water-wet to oil-wet. Another issue could be the increase in the viscosity of the oil phase due to the formation of water in oil emulsions [6,7].…”

“…This complicated association of problems can occur simultaneously during oil recovery processes. Several methods to remediate these operational problems are available such as the use of chemical additives, which have been used in the field without testing their actual effectiveness in remediating the situation [7,8]. The removal and control of formation damage caused by asphaltenes deposition are usually achieved by the application of chemical treatments based on aromatic solvents that are applied in both at the wellbore and deeper within the formation.…”

“…However, there is an economical limitation due to the transient effect of such cleanup methods. Moreover, aromatic solvents do not efficiently dissolve the heavy organic deposits or extract the asphaltenes fractions that remain fixed onto carbonated and clay minerals surfaces [7,9,10]. In the case of heavy crude oils, some of the methods that have been reported for viscosity reduction include dilution with lighter crudes or alcohols, the use of chemical additives such as polymers, or nanoparticles, and the use of surfactants to stabilize emulsions [11].…”

“…Chemical flooding using surfactants is a method that has been widely studied over several decades; it is considered an efficient process to achieve incremental recovery of residual oil with great potential as an EOR process for the petroleum industry. Although the mechanisms involved in the interactions of the surfactants with oil and brine within the porous media are complex, interfacial-tension reduction and formation rock wettability alteration are the most accepted mechanisms responsible for recovering residual oil saturation [4,7,12,13].…”