Challenges in Data Integration, Design and Modeling of the Coreflood for FWAG EOR

Abstract

Most of the Malaysian oil fields are mature and the need for IOR/EOR driven development planning is vital to maintain the national production. The most common EOR methods employed in Malaysia are immiscible WAG and CEOR. However, one of the main problems in WAG is how to control gas mobility to minimize the conformance issue and maximize the 3-phase region in the reservoir. Using Foam is a relatively cost effective way of controlling gas mobility by means of low concentration of surfactant. However, the practical implementation has been hindered due to the lack of general understanding of the complex process of foam phase behavior and flow dynamics in porous media, the absence of reliable predictive models of multi-phase foam flow, and also the challenges in upscaling the lab results to the field application.The data integration, fundamental understanding, input evaluation and predictive modeling of WAG and Foam Assisted WAG (FAWAG) have been reviewed in this work using two extensive core flooding data of one of the Malaysian oil field in two different simulators. Review of the laboratory procedure showed the importance of taking proper pre-design measures to be able to achieve conclusive results. The modeling practice shows that output parameters from coreflood experiments might be affected by forced history matching and consequently unrealistic simulation input parameters as well as the shortcomings of the predictive capability of different simulators.The study showed that in the core flood experiments and simulations, various aspects need to be carefully considered including:• Reliable data integration and understanding of the physics/dynamics involved in the process are important for proper evaluation of the foam effect. • Simulation studies to be used for the pre-design and optimization of the coreflood experiment and parameters (i.e., rate, cycles, pore volume, etc.). • The measured rates and pressures must be of consistent resolution to be able to capture the exact phase breakthroughs and precise fractional flows of the experiment. • The SCAL endpoints and WAG parameters must be measured and fixed prior to FAWAG experiment and simulation.• Capillary end effect, formation water salinity effect on contact angle and capillary pressure impact on coreflood results needs to be carefully considered in both laboratory and modeling stages. • Different commercial simulators may results in different prediction on foam output and the effect, hence proper evaluation, de-risking and sensitivity analysis should be performed to capture the foam EOR window of opportunity.

Evaluation of foam performance at different temperature for enhanced oil recovery process

“…For instance, carbon dioxide (CO 2 ) flooding helps to improve oil recovery due to the dense characteristic of the gas that can displace oil from reservoir rock (Al and Belhaij, 2015). However, there are several implications that had been associated with the implementation of gas flooding among which are poor sweep efficiency, gas channeling, viscous fingering, gravity override and breakthrough (Jalan et al, 2014).…”

An Integrated Property–Performance Analysis for CO2-Philic Foam-Assisted CO2-Enhanced Oil Recovery

“…Therefore, we are focusing on corescale model parameters fitting based on bulk and dynamic CO 2 -philic FAWAG experimental data. The mechanisms that can take place during a foaming process other than gas mobility control are listed as 33 (1) Relative permeability modifications due to rock-fluid, fluid− fluid interactions (2) Capillary force changes and oil−water miscibility due to IFT reduction (3) Foam adsorption, decay and regeneration (4) Fluid flow through the lamella To minimize the challenges involved in taking into account the role of each phenomenon in the model, it is advised for the SAG injection designer to consider measuring various parameters in the foam process in predesign experiments to obtain their range and interdependencies. Chemical reactions are designed to represent foam adsorption, decay, and desorption.…”

“…Therefore, we are focusing on core-scale model parameters fitting based on bulk and dynamic CO 2 -philic FAWAG experimental data. The mechanisms that can take place during a foaming process other than gas mobility control are listed as Relative permeability modifications due to rock-fluid, fluid–fluid interactions Capillary force changes and oil–water miscibility due to IFT reduction Foam adsorption, decay and regeneration Fluid flow through the lamella …”

Evaluation of Gas-Based EOR Methods in Gas-Invaded Zones of Fractured Carbonate Reservoir

“…The reduced gas mobility allows for a greater sweep efficiency, wherein more oil is produced in the gas cycles than pure WAG injection. The CO 2 injection in WAG is significantly less effective as it bypasses the oil and ends up being produced faster than the mobility-reduced gas of the FAWAG method [23]. According to Lake, the gas mobility reduction caused by the foam can be viewed as either an increase in the effective viscosity of a single-phase flow or a decrease in the gas-phase permeability.…”