Profile Control Using Fly Ash Three-Phase Foam Assisted by Microspheres with an Adhesive Coating

Abstract

Foam-assisted steam flooding is a promising technique to alleviate gas channeling and enhance sweep efficiency in heterogeneous heavy-oil reservoirs. However, long-term foam stabilization remains problematic at high temperatures. Three-phase foam (TPF), containing dispersed solid particles, has been proposed to improve foam stability under harsh reservoir conditions. We fabricated a novel TPF system by adding ultrafine fly ash particles, as well as high-temperature resistant microspheres with an adhesive coating layer. This work aims at assessing the ability of the generated TPF in controlling steam channeling and enhancing oil recovery. Static and core flood tests were performed to evaluate foam strength and stability. Our results suggested a stronger foamability at a lower consolidation agent concentration, while a longer half-life period of foam and settling time of solid particles at a larger consolidation agent concentration were observed. Bubbles suspended independently in the liquid phase, with sizes varying from 10 to 100 μm, smaller than that of the conventional foam, suggesting a significant enhancement of foam dispersity and stability. The plugging rate was close to 90% when the temperature was as high as 300 °C, demonstrating a well-accepted plugging effect under high temperatures. A larger pore volume injection of TPF yielded a higher EOR in parallel cores, which substantiated the effectiveness of the three-phase foam system in sealing high-permeability channels.

Experimental study on the effect of foam in preventing gas channeling in shale reservoir

“…Figures 13,14 show the strong oil production performance caused by the channeling prevention of foam. This reveals the oil recovery mechanism of foam in huff-n-puff gas injection from the perspective of micro pores, that is, it increases the swept volume of gas in micro pores, middle pores and large pores, and improves the oil recovery as a whole (Diwu et al, 2018;Zhu et al, 2018;Feng et al, 2020;Yang et al, 2021).…”

Special Issue on Multiphase Flows in Microfluidics: Fundamentals and Applications

“…There are also papers on specific engineering applications in the Special Issue. Yang et al [18] proposed a three-phase foam (TPF) containing dispersed solid particles to improve foam stability under harsh reservoir conditions. They fabricated a novel TPF system, assessed the ability of the TPF to control steam channeling and enhance oil recovery, and observed a stronger foamability at a lower consolidation agent concentration.…”