Effect of electrolytes on the self-protection of natural gas hydrate decomposition

Abstract

This paper presents an experimental study of methane hydrate decomposition with different concentrations of electrolytes Na+ and K+, with the aim of exploring the electrolyte's behaviour characteristics shown in its effect on the self-protection effect of methane hydrate during decomposition. The study used an experimental device for hydrate synthesis and decomposition. It focuses on the effect of electrolytes on the self-protection effect of methane hydrate during the self-protection effect during methane hydrate decomposition. (i) Na+ ions have an inhibitory effect on self-protection, whereas K+ ions do not have a significant effect. (ii) There is a negative correlation between the hydrate self-protection effect and the concentration of Na+ ions. However, an excessive Na+ concentration can inhibit the hydrate gas production rate. (iii) The synergistic system of Na+ and K+ ions has a better inhibitory effect on the hydrate's self-protection effect than a single Na+ ion solution. As the concentration of the synergistic system increased, the hydrate gas production rate was not inhibited. However, in contrast to a single Na+ ion solution, when the concentration of the synergistic system was too high, the methane hydrate gas production rate was not inhibited because of the coexistence of cations.