微乳体系下甲烷水合物生成和储气性能研究

Methane Hydrate Formation and Storage Capacity in Micro-Emulsion

以正癸烷为分散剂模拟油相体系,一定比例的Span80+Tween80为乳化剂,在超高速搅拌下形成油包水乳液,在自制的高压反应釜中利用恒容降压法进行甲烷水合物生成实验,探究了搅拌速度、温度、乳化剂质量分数以及'记忆效应'对于甲烷水合物生长速率和储气性能的影响.结果表明:一定范围内搅拌速度越大,温度越低,乳化剂质量分数越大,水合物生长速率越大;在273.35 K、700 r/min、2%(质量分数)Span80条件下1体积水合物能储存120倍体积的甲烷,相比于纯水体系40倍体积的储气性能有了很大提高.此外,对乳液体系下甲烷水合物生成过程进行了分析.

The W/O emulsion was prepared with n-decane as continuous phase and mixtures of Span80 ＋ Tween80 as surfactants at high stirring rate. The influences of stirring rate, temperature, mass fraction of surfactant and ＂the mem- ory effect＂ on the methane hydrate formation rate and storage capacity in the emulsion were investigated in a high pressure reactor during isochoric process. Results show that hydrate formation rate increases with higher stirring rate, lower temperature and higher mass fraction of surfactant. The storage capacity is 120 （volume ratio of methane to hy- drate） in the emulsion under 273.35 K, 700 r/min and 2% （mass fraction）Span80, which is much greater than 40 （vol- ume ratio of methane to hydrate） in pure water. Furthermore, the process of methane hydrate formation in emulsion was analyzed.