二氧化碳水合物导热和热扩散特性

Characteristics of thermal conductivity and thermal diffusivity of carbon dioxide hydrate

热导率和热扩散率是天然气水合物资源开采关键性基础热物性数据,采用反应釜内壁衬有氟塑料材料,低过冷度,让水合物在反应釜内逐层生成的合成方法,获得可直接用于导热测试的二氧化碳水合物样品。采用瞬变平面热源法原位测试了温度264.68-282.04 K、压力1.5-3 MPa二氧化碳水合物热导率、热扩散率,并测试了二氧化碳水合物在268.05 K、0.6 MPa左右发生自保护效应过程中热导率、热扩散率,获得了晶态下和自保护效应过程中的二氧化碳水合物热导率、热扩散率变化特性。测试结果将为天然气水合物资源的开发利用提供基础数据和理论依据。

Thermal conductivity and thermal diffusivity are two key basic factors of thermal property data that determine gas hydrate resource extraction. In this study, carbon dioxide hydrate sample was formed from a supersaturated carbon dioxide gas solution and layer by layer formed with the equal thickness in the reactor cell lined with fluorine plastics. The thermal conductivity and thermal diffusivity of carbon dioxide hydrate were in-situ measured by means of transient plane source technique. The measurements were performed at 264.68—282.04 K and 1.5—3 MPa. The measurements were also performed during self-preservation effect process at 268.05 K and 0.6 MPa. The characteristics of thermal conductivity and thermal diffusivity of carbon dioxide hydrate were obtained on crystalline state and during self-preservation effect process. The results of this paper can provide basic data and theoretical basis for the development and utilization of natural gas hydrate resources.