【作者】 刘强；

【导师】 王振波；

【作者基本信息】 中国石油大学（华东） ， 动力工程及工程热物理， 2013， 硕士

【摘要】 天然气水合物（natural gas hydrate，简称NGH），又叫“可燃冰”，含有大量的甲烷或其他碳氢气体，极易燃烧。在同等条件下“可燃冰”燃烧所产生的能量比煤、石油、天然气等常规能源要高出数十倍，其应用范围与天然气基本相同，是一种典型的石油替代品。天然气水合物在自然界中的储量十分丰富，目前已有多个国家进行了天然气水合物的开发利用试验。目前对于天然气水合物的开采，常用的有热激法、降压法及化学抑制剂法，天然气水合物分解产生的水与游离气一同返回地面再进行分离处理。本课题在现有水合物开采经验基础上，提出一种天然气水合物排水采气工艺方案。该方案将热激法与降压法相结合，利用井下轴流导叶式气液分离器对进入井筒的气液混合物进行分离，并用电潜泵系统将井底积水人工举升至地面，从而降低采出气中液体含量，解决天然气水合物矿藏高产水带来的气井积液问题。本文初步建立天然气水合物排水采气室内模拟试验装置系统，并对模拟装置的气液分离器性能与存液腔内液位控制进行试验研究。气液分离试验研究操作参数与结构参数结对分离器性能的影响，结果表明：进气量对分离器性能影响作用明显；进水量对分离器性能的影响较进气量弱；排水管对分离器内流场具有影响；导叶角度为25°时，分离器性能较好。排水试验利用变频器与液位检测装置对存液腔内液位进行闭环控制，可将液位稳定在设定值处，初步验证了排水采气方案的可行性。更多还原

【Abstract】 Natural gas hydrate (short for NGH), also called “flammable ice”, contains plenty ofmethane or other hydrocarbon gas，and is flammable. The energy produced by the NGH isdozens of times higher than the conventional energy sources such as coal, oil and natural gasin the same condition. The NGH has the same application range with natural gas, and does notproduce any residue and waste gas after combustion, so it is considered as a substitute forpetroleum. NGH is very rich in the world, and many countries have conducted the experimentin exploiting NGH.Three kinds of methods are usually used in the NGH’s exploitation: thermal-stimulationmethod, depressurizing method, chemical inhibitors method. The water and gas produced byNGH rise to the ground together. In this paper, a new NGH’s drainage gas recovery methodbased on the existing exploitation techniques is proposed.In this method, an axial flow guidevane type gas-liquid cyclone separator is used downhole to separate the gas-liquid mixture,and electric submersible pump system is used to lift the separated water to the ground.The simulation test installation is reasonable design and built, the gas-liquid separationtest and the liquid level control test are conducted. The results show that the air inflowinfluences the separation performance seriously, the drain-pipe can influence the separator’sflow field, and the guide vane of25°has the better efficiency. The closed loop control systemused in the liquid level control system can steady the liquid level at the designated level.更多还原