Polymer-Enhanced Foam Flooding for Improving Heavy Oil Recovery in Thin Reservoirs

Abstract

Oil reserves of the thin heavy oil reservoirs are estimated to be over 400 billion barrels. The recovery factor of waterflooding in these reservoirs is as low as 10−20% due to the high oil viscosity and correspondingly unfavorable mobility ratio. In addition, the commonly used thermal recovery methods are also unsuitable in such formations due to the significant heat loss to the adjacent formations. Thus, it is urgent to find an efficient and economic enhanced oil recovery (EOR) method to maximize the recovery factors in the thin heavy oil reservoirs. In this study, the feasibility of polymer-enhanced foam (PEF) flooding for the thin heavy oil reservoirs is investigated using the micromodel and core-flood experiments. The micromodel experiments show that foam quality has significant effects on the resistance factor and heavy oil recovery of the PEF flooding, where the displacement front of a low-quality foam case is more even than that of a high-quality foam case and surfactant−polymer (SP) flooding case. Core-flood tests further reveal that there is an optimal slug size under the experimental conditions, and the heavy oil recovery of PEF flooding is 23.9% higher than that of SP flooding when using the same slug size. Finally, a field-scale reservoir simulation is conducted, and the results show that after initial water-flooding in thin heavy oil reservoirs, the recovery factor achieved by the PEF flooding is 11.7% higher than that of the SP flooding and 21.4% higher than that of the continuous water-flooding process.

The Supercritical Multithermal Fluid Flooding Investigation: Experiments and Numerical Simulation for Deep Offshore Heavy Oil Reservoirs

“…The decline of light oil production and the exhaustion of onshore heavy oil resources lead to an increasing demand of offshore heavy oil [1,2]. Due to high but the temperature-dependent viscosity, the development regimes of offshore heavy oil, especially for oil with viscosity exceeding 350 mPa•s, can only be effectively extracted by thermal methods [3,4].…”

A Numerical Model for Investigating the Steam Conformance along the Dual-String Horizontal Wells in SAGD Operations

“…Heavy oil is an important energy source [1][2][3][4], and Steam-assisted gravity drainage (SAGD) is an effective technology for the economic recovery of heavy oil [5][6][7][8]. The SAGD process usually employs two parallel horizontal wells.…”

“…The heat transfer in the wellbore is steady state, while the heat transfer in the reservoir is transient. 4.…”

“…w − S g ϕ + U w ρ w ϕδS w + S w ϕ ∂ρ w ∂P o δP o + S w ϕ ∂ρ w∂T δT + S w ρ w4 Equilibrium Equation (A47) can be changed as shown below:…”

Dynamic and static gelation behavior of phenol formaldehyde resin gel system in ampoule bottles and porous media

“…The proven technology of water shutoff and conformance control used polymer gel has been widely introduced to block the high permeable zone, realize in-depth flow diversion and enhance sweep efficiency (James et al, 2003;Mercado et al, 2009;Ojukwu et al, 2007;Wang et al, 2019;Zhou et al, 2020). Several kinds of polymer gels have been used in oilfield, including inorganic metal ions gel system (McCool et al, 2009), Phenol Formaldehyde Resin (PFR) gel system (Banerjee et al, 2006), polyethyleneimine gel system (Al-Muntasheri et al, 2009) and so on.…”