Research of an Efficient Foam Drainage Agent for Gas Well Production

In natural gas production, foam drainage is needed to ensure the continuous production of natural gas. Efficient foaming agents have always been a research focus in this field. Foaming performance of a composite surfactant formulation containing dodecyl betaine (BS-12) and sodium α-olefin sulfonate (AOST) was evaluated in this study to meet the application requirements of gas well foaming and defoaming. The results showed that the foaming volume of the compound surfactant solution (0.1 wt% AOST + 0.3 wt% BS-12) could reach 520 mL, respectively, and the foaming capacity and stability were improved compared with those of the solution containing a single surfactant. Surface tension was shown to be reduced to 26.4 mN∙m−1 in the presence of the compound surfactant. Meanwhile, the microstructure of the foam was observed using polarized light microscope and the foam showed good stability. The experimental results also demonstrated good temperature and salt resistance of the formulation.