GOALI: Structure and Stability of Gas Hydrates - Probing the Mechanism of Binary Gas Hydrate Decomposition

斯隆，E. Dendy等人/杰斐逊L.克里克科罗拉多矿业学院/雪佛龙德士古“目标：天然气水合物的结构和稳定性-探索二元天然气水合物分解机制。”甲烷、乙烷和二氧化碳是三种最重要的天然气水合物。这些都是潜在的丰富能源。甲烷+乙烷和甲烷+二氧化碳双水合物的尺寸范围适合于对结构I和结构II水合物平衡和分解过程进行详细的实验和理论研究。实验技术将在拟议的工作中使用的是核磁共振波谱和中子衍射。本课题拟测量甲烷+乙烷和甲烷+二氧化碳双水合物体系的压力-温度-组成关系。提出的工作将研究水合物分解以及这些双水合物的平衡性质作为三个变量的函数：。甲烷摩尔分数为0 ~ 1时的气相组成。温度范围为233 ~ 283 k。压力范围约为450 ~ 4000kpa。提出的工作将建立基于分子尺寸-空腔尺寸比概念的定量模型，用于预测天然气水合物的结构和稳定性。这些模型将从理论上的Langmuir吸附系数计算发展而来。在平衡状态下，甲烷+乙烷和甲烷+二氧化碳的双水合物特别适合这些类型的研究，因为甲烷+二氧化碳应该只形成结构I水合物，而甲烷+乙烷和建议工作中的理论研究提供了对气体水合物的分子水平的理解。包括教育和技术在内的更广泛的影响如下：拟议的工作将有助于促进科罗拉多矿业学院化学科学的研究生和本科生教育和研究。参与提议工作的研究生和本科生都应该在同行评审的期刊上发表他们的工作成果，并参加科学会议，以展示他们的工作成果。总体而言，学生和项目将受益于与雪佛龙德士古能源技术公司J. Creek博士（共同负责人）的智力合作。克里克博士将帮助指导项目团队对工作的工业相关性。天然气和石油能源行业的能源回收和水合物堵塞补救策略也将受益于拟议工作中产生的知识。水合物地层中所含气体的量取决于水合物结构和宾客分数占有。根据项目开发的信息，水合物塞结构和地层条件也将得到更好的了解。

Sloan, E. Dendy et al / Jefferson L. CreekColorado School of Mines / ChevronTexaco "GOALI: Structure and Stability of Gas Hydrates - Probing the Mechanism of Binary Gas Hydrate Decomposition."Methane, ethane and carbon dioxide are three of the most important natural gas hydrates. These are potential rich energy sources. Double hydrates of methane + ethane and methane + carbon dioxide span a size range suitable to provide detailed experimental and theoretical investigations of Structure I and Structure II hydrates at equilibrium and during decomposition. The experimental techniques to be used in the proposed work are NMR spectroscopy and neutron diffraction. This project proposes to measure pressure-temperature-composition relations in the methane + ethane and methane + carbon dioxide double hydrate systems. The proposed work will study hydrate decomposition as well as equilibrium properties of these double hydrates as a function of three variables: . The gas phase composition for methane mole fractions of 0 to 1. . The temperature range of 233 to 283 K. . The pressure range of about 450 to 4000 kPa. The proposed work will develop quantitative models based on the molecular size -- cavity size ratio concept to be used to predict the structure and stability of natural gas hydrates. These models will be developed from theoretical Langmuir adsorption coefficient calculations. At equilibrium the double hydrates methane + ethane and methane + carbon dioxide are particularly appropriate for these types of studies because methane + carbon dioxide should only form Structure I hydrate while the methane + ethane and theoretical studies in the proposed work provide for a molecular level understanding of gas hydrate. The broader impacts including educational and technical are as follows: The proposed work will help foster both graduate and undergraduate education and research in the chemical sciences at the Colorado School of Mines. Both graduate and undergraduate students who participate in the proposed work are expected to publish the results of their work in peer-reviewed journals and to attend scientific conferences in order to present results based on their work. The students and project in general will benefit from the intellectual collaboration with Dr. J. Creek (co-PI) of ChevronTexaco Energy Technology Company. Dr. Creek will help guide the project team on the industrial relevance of the work. Strategies for energy resource recovery and hydrate plug remediation in the gas and oil energy industries will also benefit from the knowledge generated in the proposed work. The amount of gas contained in hydrate formations depends on the hydrate structure and guest fractional occupancy. Hydrate plug structure and formation conditions will also be better understood based on information developed in the project.