Stabilization of natural gas foams using different surfactants at high pressure and high temperature conditions

Abstract

Natural gas foam can be used for mobility control and channel blocking during natural gas injection for enhanced oil recovery, in which stable foams need to be used at high reservoir temperature, high pressure and high water salinity conditions in field applications. In this study, the performance of methane (CH 4 ) foams stabilized by different types of surfactants was tested using a high pressure and high temperature foam meter for surfactant screening and selection, including anionic surfactant (sodium dodecyl sulfate), non-anionic surfactant (alkyl polyglycoside), zwitterionic surfactant (dodecyl dimethyl betaine) and cationic surfactant (dodecyl trimethyl ammonium chloride), and the results show that CH 4 -SDS foam has much better performance than that of the other three surfactants. The influences of gas types (CH 4 , N 2 , and CO 2 ), surfactant concentration, temperature (up to 110 C), pressure (up to 12.0 MPa), and the presence of polymers as foam stabilizer on foam performance was also evaluated using SDS surfactant. The experimental results show that the stability of CH 4 foam is better than that of CO 2 foam, while N 2 foam is the most stable, and CO 2 foam has the largest foam volume, which can be attributed to the strong interactions between CO 2 molecules with H 2 O. The foaming ability and foam stability increase with the increase of the SDS concentration up to 1.0 wt% (0.035 mol/L), but a further increase of the surfactant concentration has a negative effect. The high temperature can greatly reduce the stability of CH 4 -SDS foam, while the foaming ability and foam stability can be significantly enhanced at high pressure. The addition of a small amount of polyacrylamide as a foam stabilizer can significantly increase the viscosity of the bulk solution and improve the foam stability, and the higher the molecular weight of the polymer, the higher viscosity of the foam liquid film, the better foam performance.

Impact of Eco-Friendly Drilling Additives on Foaming Properties for Sustainable Underbalanced Foam Drilling Applications

“…This barrier effect prevents the formation of larger bubbles and promotes the retention of smaller, more stable bubbles within the foam structure, leading to a prolonged half-life. Such a positive impact of PAC on foam stability was also noticed in previous studies. , When the PAC concentration was further increased to 1.0 g/L, there was only a minimal extension in foam stability. This suggests that the additional amount of PAC was insufficient to create a significant improvement in the formed barrier and stabilize the foam significantly further.…”

“…Such a positive impact of PAC on foam stability was also noticed in previous studies. 37,38 When the PAC concentration was further increased to 1.0 g/L, there was only a minimal extension in foam stability. This suggests that the additional amount of PAC was insufficient to create a significant improvement in the formed barrier and stabilize the foam significantly further.…”

The development of heat‐resistant and salt‐tolerant foam with betaine surfactants

“…Much research regarding the bulk foam properties under the conditions of high temperature (90–130°C) and high pressure (1–8 MPa) had been done, the most commonly used methods included the bubbling method and blender method. (Bi et al, 2022; Zhang et al, 2018) When the bubbling method was adopted, the nitrogen or air was sparged at a constant flow rate through surfactant solutions and foam was generated. Initial foam volume and foam half‐time could be easily obtained in these experiments, however, there was still much remaining surfactant solution after completing the foam generation.…”

Effects of Different Gases on the Molecular Behavior of Alkyl Glycosides at Gas/Liquid Interface and Foam Stability

“…[10] Zeng et al [11] discussed the influence of different types of gas and composition on foam stability by comparing gas solubility, gas diffusion rate, and foam stability. Bi [12] et al investigated the effects of N 2 , CO 2 , and CH 4 conditions on the performance of SDS foam, showing N 2 foam to have the strongest stability. These studies were based on macroscopic experimental phenomena using the rate of gas diffusion and foaming ability to evaluate gas characteristics, such as its impact on foam stability; however, these research methods did not supply detail at the molecular level to expound on how to affect the stability of foam gas.…”

“…discussed the influence of different types of gas and composition on foam stability by comparing gas solubility, gas diffusion rate, and foam stability. Bi [12] et al. investigated the effects of N 2 , CO 2 , and CH 4 conditions on the performance of SDS foam, showing N 2 foam to have the strongest stability.…”