天然气水合物是目前备受关注的新型洁净优质能源，注热盐水是一种有效的开采方式。采用自制的一维天然气水合物(NGH)开采模拟实验装置，首先在填砂模型中生成初始条件相同的天然气水合物藏，之后注入盐度为2%、10%、20%的热水进行开采实验。结果表明：当注热水盐度较大(达到10%后)时，水合物快速分解，与自由气同时产出，产气速率峰值较大；而当注热水盐度较小(2%)时，自由气首先产出，然后水合物分解气体产出。注热水盐度越大，水合物分解速度越快，热前缘移动速率越大，水合物大量分解阶段的能量效率越高。因此，注热水盐度的增加可以加快天然气水合物的开采速率，增大注热开采的经济可行性。%Natural gas hydrate(NGH) is a new clean and effective energy resource. Hot brine injection is a successful mining method and the salinity of hot brine has big influence on the equilibrium of NGH. Therefore, how the salinity affects the thermal dissociation is very important. A self-made one-dimensional experimental setup was introduced to dissociate NGH with same initial conditions, and then hot brine with different salinities (2%,10%,20%) was injected to study the effect of hot brine salinity on NGH dissociation. Results show that brine salinity has a large effect on NGH dissociation. When the brine salinity was over 10%, NGH was dissociated fast and free gas from NGH dissociation was simultaneously produced that resulting in a large gas production rate. For 2% brine salinity, free gas production and gas release from NGH dissociation happened one after another. Higher brine salinity results in faster NGH dissociation rate, quicker thermal front movement of NGH and higher energy efficiency. Therefore, the NGH dissociation rate and the dissociation feasibility accelerated with the increase of hot brine salinity.
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