Synthesis and Dissociation of Gas Hydrate with Added Biosurfactants

Microorganisms located in the hydrate pores produce biosurfactants that reduce the surface tension of water. However, the effect of biosurfactants on the characteristics of hydrate synthesis and dissociation is understudied, although it could significantly improve the efficiency of gas extraction from hydrates. In this study, the kinetics of methane hydrate formation and dissociation was investigated in the presence of three biosurfactants. Three regasification stages were identified. It was found that adding 0.5 vol % Surfactin, C5H12N2O2, or C2H7NO3S to an aqueous solution reduces the methane hydrate synthesis time by 21, 13.7, and 11%, respectively. Adding 10 vol % sand to an aqueous solution of Surfactin reduced the hydrate synthesis time by 24%, but the gas saturation was 6–10% less than that when using other additives. During the dissociation of methane hydrate with Surfactin, the rate of this process increased by 12–62% compared to hydrates with C5H12N2O2 and C2H7NO3S. Based on the obtained results, equations were derived to predict the hydrate dissociation time as a function of its heating intensity. Finally, a conceptual technology was proposed for the environmentally friendly heat generation using gas hydrates on the basis of the research findings.