天然气水合物(可燃冰)生成机理和热力学模型研究毕业论文.doc

毕业论文 天然气水合物生成机理和热力学模型研究 摘要 目前解决能源需求的问题显得越来越紧迫。开发利用新的清洁能源，降低能源使用与技术发展对环境造成的负面影响，是解决本世纪能源问题的主要出路。在我国能源发展战略中，高效、清洁的天然气水合物将成为重要的后续能源。在天然气水合物的研究方面，相平衡是天然气水合物开采和各种应用技术的基本原理，因此对天然气水合物相平衡热力学模型的研究十分重要。本论文针对目前存在的热力学模型进行分析研究，选取不同的热力学模型，运用BWRS状态方程结合单级平衡分离过程求取逸度对模型进行有效修改，最后在陈郭和杜郭模型的基础上选取三种不同的计算方法。通过编程对不同组分的气体进行预测计算，实现了对现有模型的综合性评价，确立了较好的热力学模型。此外本文还针对含有醇、盐抑制剂的体系进行编程计算，并将其与不含抑制剂体系进行比较。结果表明：以陈郭模型基础上的计算方法，在压力稍高时较为精确，以杜郭模型为基础的计算方法在压力较低时依然可以得到较好的预测结果。对于加入抑制剂的体系，在相同压力下，同一组分的生成温度明显降低。最后对管道天然气水合物的形成、防治及预防进行了介绍。 关键词：天然气水合物 热力学模型 逸度 活度 抑制剂 Research on Natural Gas Hydrate Formation and Thermodynamic Model Abstract The problem of energy shortage is becoming more and more urgent currently. Developing new clean energy, reducing the negative influence of the energy utilization and technology development for the environment are the main solutions to the energy problem of this century. In our country’s energy development strategy, high-efficient and clean natural gas hydrate will be an important energy resource. On the research of the natural gas hydrates, phase equilibrium is the basic principle of recovering the natural gas equilibrium and various application technologies, so it is very important to study the natural gas hydrate phase equilibrium thermodynamic models. The various thermodynamic models were analyzed and studied in this paper, and also revised through the application of BWRS state function and combining single stage equilibrium separation process for the fugacity, in the end three kinds of calculation methods were selected on the basis of Chen-Guo and Du-Guo models. The gas with different components were calculated and predicted through programming, and the current models were thoroughly evaluated, a better model was established. Besides the system with alcohol, salt inhibitors were calculated and compared with the system without inhibitors. It is shown that the method of Chen-Guo modal is more accurate when the pressure is high, whereas the Du-Guo modal is better under t