太赫兹电磁波调控甲烷水合物分解  

THz electromagnetic wave regulated dissolution of methane hydrate

作　　者：朱智 闫韶健 段铜川 赵妍[1] 孙庭钰 李阳梅 Zhu Zhi;Yan Shao-Jian;Duan Tong-Chuan;Zhao Yan;Sun Ting-Yu;Li Yang-Mei(Key Laboratory of Optical Technology and Instrument for Medicine,Ministry of Education,College of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Innovation Laboratory of Terahertz Biophysics,National Innovation Institute of Defense Technology,Beijing 100071,China)

机构地区：[1]上海理工大学光电信息与计算机工程学院,教育部医用光学仪器与设备重点实验室,上海200093 [2]国防科技创新研究院,太赫兹生物物理创新工作站,北京100071

出　　处：《物理学报》2021年第24期353-360,共8页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2021YFA1200404);国家自然科学基金(批准号:11904231);上海市青年科技英才扬帆计划(批准号:19YF1434100);国防科技创新特区资助的课题.

摘　　要：甲烷水合物具有分布范围广、资源储量大、能量密度高、清洁无污染等特点,因此一经发现便得到人们的广泛关注.虽然如此,甲烷水合物的开采存在较多的困难,主要涉及笼型甲烷水合物的分解过程,因此本文通过分子动力学模拟,探索太赫兹电磁波对该水合物分解的特异性影响.通过分析甲烷水合物中水分子的振动谱,发现其区别于体相水在低温下的特异性振动峰.通过引入频率与该振动峰中心频率一致的太赫兹波发现,该电磁场会破坏甲烷水合物原有的氢键网络,降低甲烷周围水分子的配位数,从而使甲烷分子从水笼中脱离.进一步地,对序参数F_(4)的分析也证明,在太赫兹电磁刺激下,甲烷壳层水由原来的晶体水变成了液态水.同时证明了该频率具有相比于其他频率的绝对优势,因此具有其特异性.本文的发现有望通过非热效应来实现甲烷水合物的分解,高效、低能耗地提高开采效率,推动未来新能源的发展.Methane hydrate(so-called flammable ice)has many advantages such as wide distribution,large resource reserves,high energy density,being clean and pollution-free,etc.Thus,it has attracted much attention since it was discovered.Unfortunately,its exploration encounters many difficulties,which involve mainly with the dissolution process of caged methane hydrate.Therefore,in this work the specific effect of THz electromagnetic wave on decomposition of the hydrate is explored through molecular dynamics simulations.Analyzing the vibrational spectrum of the hydrogen-bond network in methane hydrate,no specific absorption peak is found in the bulk water.Applying a THz wave at this specific frequency to the methane hydrate,the original hydrogen-bond network is broken,the coordinate number of water molecules for the methane decreases,and ultimately the methane frees from the water cage.The F_(4) ordered parameters further validate the phase change from the crystal water to liquid water under the same THz field irritation.It is also proved that this peak absorption frequency has a remarkable superiority over other frequencies in decomposing the methane hydrate,hence it has specificity.Our findings support the feasibility of non-thermally dissolving methane hydrate,which promises to promote the exploitation efficiency and development of new energy sources in the future.

关 键 词：太赫兹 甲烷水合物 氢键 分解 分子动力学 

分 类 号：TE31[石油与天然气工程—油气田开发工程] O441.4[理学—电磁学]