Immiscible Foam for Enhancing Oil Recovery: Bulk and Porous Media Experiments

Abstract

This paper reports a laboratory study of foams intended to improve immiscible gas flooding in oil production. The study is relevant for both continuous and water alternating gas (WAG) injection schemes. The effect of oil on the longevity of nitrogen and air foams was studied in bulk for a selected set of surfactants. Foam heights were measured in a glass column as a function of time, in the absence and presence of mineral and crude oils. The column experiments indicated that foam longevity increases as the carbon chain length in the oil molecule increases; that is, foam is generally more stable in the presence of higherviscosity oils. The surfactant formulation that gave the most stable foam in the presence of oil was used in core floods. Oil recovery from natural sandstone cores with CO 2 and with N 2 foams was studied with the aid of X-ray computed tomography, while the injection rates, foam quality, and surfactant concentration were varied. The core floods revealed that foam increases oil recovery by as much as 20% of the oil initially in place (OIIP) as compared with water flooding, while gas injection increases oil recovery by 10% only. Thus, foam can achieve an additional recovery of up to 10% relative to gas injection. This confirms that foam is potentially an efficient enhanced oil recovery (EOR) method.

Foam stability in the presence and absence of hydrocarbons: From bubble- to bulk-scale

“…Others, however, have shown that stable foams can be generated in the presence of oil if an appropriate foaming agent is selected [22,26,27]. It has also been demonstrated that foam can be generated effectively in the presence of heavy oil [28,29]. Indeed, there are other experiments that suggest that oil can improve the stability of foam.…”

Application of foam floods for enhancing heavy oil recovery through stability analysis and core flood experiments

“…Furthermore, the surfactants molecules demote the gas/ liquid interfacial tension and thereby contribute to the formation of small bubbles. [14] Foam Application in Enhanced Oil Recovery Immiscible gas injection can potentially increase the recovered oil from the reservoir, but one of the main drawbacks that is associated with immiscible gas injection processes is the gas segregation and fingering through the high permeability region in the reservoir. [15][16][17] These phenomena are due to a large contrast between the viscosity and density of gas compared to oil.…”

“…Also they showed that oil recovery and pressure drop across the core increased when the stability of the foam increases. Andrianov et al, [14] through a series of bulk experiments, showed that foam stability depends on the oil and surfactant molecules carbon chain length. They reported that oils with a higher carbon number affect foam stability less than those with a lower carbon number.…”

“…The previous reported experiences showed that there is a great wealth of studies dealing with effect of oil phase on foam stability. However, few researchers [14,43,45] have tried to do a comprehensive study on the effect of type of injected gas, salinity, surfactant type, and presence of alkaline on foam stability.…”

Stability and shear thixotropy of multilayered film foam

“…It has been successfully utilized in a large variety of emerging fields recently, such as blast mitigation [1], an intermediate structure to produce porous materials [2][3][4] and scaffolds for tissue engineering [5,6], in addition to the traditional applications of froth flotation [7], cosmetics [8], and enhancing oil recovery [9]. Although these applications are reliant upon stable foam in general, foam is a thermodynamically unstable system on account of high gas-liquid interface area.…”