A Ternary Surfactant System for Dual Function Foam Drainage and Hydrate Anti Caking in a Gas Well

Abstract In this paper, an integrated agent named TSE containing surfactants, such as cetyltrimethylammonium chloride (CTAC), sodium aliphatic alcohol polyoxyethylene ether sulfate (AES), and dodecyl dimethyl betaine (BS‐12), was composed and employed as oil field additive with dual functions: foam drainage and hydrate anti‐agglomeration. The results show that the optimized formula achieved an initial foam volume of 565 mL with a long half‐life of 7–8 min. No settlement and stratification after 24 h further confirm the well stability of the formed foam. Good salt and methanol resistance of TSE can be found even the addition of methanol and sodium chloride. Moreover, it was demonstrated that TSE exhibited a comparable high liquid carrying rate of 77.5 wt% at 65 °C even in the presence of kinetic hydrate inhibitor. The reduction of hydrate phase transformation point indicates TSE well thermodynamic properties.