Production Optimization under Injection of Biopolymer, Synthetic Polymer and Gels in a Heterogeneous Reservoir

Abstract

Water injection increases the percentage of recovery by means of providing pressure support and displacing the oil in the heterogeneous porous medium. In such a displacement process, mobility ratio is important for a more efficient displacement of oil by the injected fluid where mobility ratio can be improved using the fluids involving gelling agents, resulting in increased volumetric sweep. While polymers degrade and break up upon experiencing sudden extreme shear stresses and temperatures, polymer macromolecules are forced to flow into narrow channels and pores, molecular scission processes can take place, thus it is of outmost importance to have a strong understanding of use of right type and amount of viscosity reduction agent. For polymer injection, a comparison of xanthan polymer and synthetic polymer mechanisms was conducted. A commercial full-physics reservoir simulator is coupled with a robust optimization and uncertainty tool to run the model where a simplified gel kinetics is assumed to form a microgel with no redox catalyst. Water injection continues over all 6 layers for 450 days, followed by gel system injection for 150 days, in the bottom 2 layers. Water injection is continued to 4 years. The top four layers have higher horizontal permeabilities, and a high-permeability streak is at the bottom of the reservoir to reduce any helpful effects of gravity. Control and uncertainty variables are set to investigate the sensitivity under this process using the coupled optimization and uncertainty tool. Results demonstrate deep penetration of gel and blocking of the high permeability bottom layers. Sensitivity studies indicate the relative merits of biopolymer, xanthan polymer in terms of viscosity effects vs synthetic PAM in terms of resistance factor vs insitu gelation treatments and their crossflow dependence. Adsorption and retention of polymer and gel are permeability dependent. Considering the fact that there is a significant potential for application of gel solutions in the US and throughout the world, this study illustrates the relative advantages of different treatments in terms of viscosity reduction in the same model in a comparative way outlining the significance of each control and uncertainty variable for better management of reservoirs where displacement efficiency is very critical.

Sensitivity Analysis Comparisson of Synthetic Polymer and Biopolymer using Reservoir Simulation

“…It occurs because of signifi cant diff erence of their viscosities. The result of this research is similar to previous research done by (Temizel, et al, 2016). Adsorption of synthetic polymer nearly production well after 10 years of injection, whereas biopolymer adsorption only touches half of reservoir (grid).…”

“…STARS is the only simulator that accounts for the complex phenomena required to accurately model processes such as Alkaline-Surfactant-Polymer (ASP) fl ooding, low salinity water injection, and foam fl ooding. The approachment used has been applied by many previous studies, such as; Temizel, et al, 2016 andErfando, et al, 2019. Sensitivity study on this research focuses on the eff ectivity of polymer injection on polymer adsorption. Reservoir grid used is multilevel homogeneous reservoir 15x15x4 assuming single production well and one injection well.…”

“…Table 1 Reservoir fl uid characteristic (Pertamina 2016;Erfando, et al, 2019) Table 2 Reservoir rock characteristic (Pertamina 2016;Erfando, et al, 2019) Table 3 Polymer properties (Temizel, et al, 2016) Table 4 Polymer fl ooding injection parameter concentration of polymer adsorbed on the rock and the concentration of polymer in the surrounding water phase (Hidayat & ALMolhem, 2019).…”

The Potential of Crab Chitosan Polymer as EOR Injection Fluid

“…One of the most used methods is polymer injection [2]. Polymer injection is one of the most important part due to its ability to increase water viscosity, lower mobility ratio, and enhance sweep efficiency and recovery factor [3,4]. During polymer injection implementation, mobility ratio of driving and driven fluids will be improved and oil sweep efficiency will be increased [5].…”

A Study on Evaluation and Optimization of Gel Flooding in Liaohe Oil Field

“…Generally, the heterogeneity of reservoir depends on the depositional environment and subsequent events. The important thing to be understood is that there are no homogenous reservoirs, only varying degree of heterogeneity exists worldwide [2]. Reservoir heterogeneity can broadly be classified into three classes-microscopic heterogeneity that is characterized at pore scale; macroscopic heterogeneity that is represented at well or intra formation scale and; megascopic heterogeneity which is at field wide or regional levels [3].…”