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.

Conformance improvement is the key to success in most enhanced oil recovery (EOR) processes including CO2 flooding and steamflooding. In spite of technical and economic limitations, foam has been used as dispersions of microgas bubbles in the reservoir to enhance mobility. Steam-foam has numerous applications in the industry, including heavy oil reservoirs, which are a significant part of the future energy supply. Steam-foam applications have been used to prevent steam channeling and steam override, thus improving overall sweep efficiency, in both continuous steam and cyclic steam injection processes. The objective of this study is to investigate the key components of this complex process, where relatively high temperatures are recorded, in order to have a robust understanding of chemistry and the thermal stability of surfactants. The efficiency and therefore economics of the steam-foam process are strongly reliant on surfactant adsorption and retention. This requires a good understanding of the process for effective sizing of the foam injected. In this study, a commercial reservoir simulator is used where surfactant transport is modeled with surfactant availability and is determined by a combination of surfactant adsorption, surfactant thermal decomposition, and oil partitioning due to temperature. The degree of mobility decrease is interpolated as a result of factors that contain aqueous surfactant kind and concentration, the presence of an oil phase, and the capillary number. An empirical foam modeling method is employed with foam mobility decrease treated by means of modified gas relative permeability curves. The simulation results outline the sensitivity of these parameters and controlling agents, providing a better understanding of the influence of surfactant adsorption and thus, a number of chemicals to be used in an efficient manner. Optimum values for decision parameters that we have control on have been determined by coupling a commercial optimization software with the reservoir simulator. Uncertainty parameters such as surfactant adsorption have been analyzed in terms of significance on the recovery process. Even though steamflooding is thoroughly studied in the literature, there is no recent in-depth study that not only investigates the decision parameters but also uncertainty variables via a robust coupling of a reservoir simulator and an optimization/uncertainty software that model use of foam in steamflooding. This study aims to fill this gap by outlining the optimization workflow, the comparison of parameters with tornado charts and providing useful information for the industry.

Multiple analysis has indicated that over 50% of the oil production in the next 20-25 years is going to be produced through enhanced recovery procedures including polymer flooding. The heuristics for polymer flooding says that it is feasible to apply polymer flooding in reservoirs having oil viscosities in the range of 10 to 150 mPa.s. The main factor limiting this heuristic limit for polymer floods is that the injected water viscosity required for higher mobility ratio leads to pumping inefficiencies and low polymer injectivity rates. In this paper, we suggest a supramolecule based on the complexation of a long-chain amino-amide and maleic acid which can adjust its viscosity values reversibly to overcome the heuristic problem related to polymer floods. The concept is fundamentally based on the fact the supramolecule system which is injected in the reservoir will initially be maintained at a low viscosity and on application of external pH stimuli will increase in viscosity values prior to contact with oil. Our laboratory studies indicate that such a system is also tolerant to high temperatures and salinities Popular polymer systems used floe EOR purposes on experiencing extreme shear stresses and temperature break-up and degrade, however the supramolecule system dissemble and reassemble making the supramolecular system "healable" in a manner. The supramolecular systems can also adapt to confining environments, for example, on flow through narrow channels, the supramolecules undergo molecular scission. The supramolecules proposed could be used for viscous oil in thin oil sand zones, permafrost and other environmentally constraining systems. This paper primarily focusses, on the development and properties of a novel supramolecular system which has adjustable viscosities and interfacial properties and can be resistant to high temperatures and salinities. This Supramolecular system can significantly improve the feasibility and cost-effectiveness of a polymer flood process and can be utilized universally.