Effect of ions on Methane Hydrate Phase Equilibrium in Deep-Water Environment of “Haima” Cold Seep

Abstract

The mechanism researches on seabed methane fate are a critical part to reveal the global methane budget. Hydrate formation by natural gas bubbles in the course of seepage is an essential way for methane capture and fixation. Nevertheless, the hydrate phase equilibrium characteristics that affect the stability of hydrate formation during the bubble ebullition process are unclear. "Haima" cold seep is a typical active methane seeping environment associated with abundant methane hydrate, which necessitates unveiling the stability of methane hydrate formation. This work investigated the hydrate phase equilibrium conditions based on the insitu water depth and practical ion categories and salinity. The results show that the strength of inhibition of methane hydrate in chloride salts of 3.45wt% salinity was in the order of