Abstract:

Gas hydrate technology has broad application prospects in the seawater desalination, hydrate cold storage, carbon dioxide storage, etc. The rapid hydrate formation is considered to be one of the key issues restricting the application of hydrate technology. The self-built CO₂ hydrate visual generation experimental device was used to conduct experimental research on the CO₂ hydrate generation characteristics in nanofluids, and the impact of nanoparticles on the CO₂ hydrate generation characteristics was analyzed. The results show that in the nanofluidic system, the gas consumption is increased by 2.17 mmol/mol but the induction time is shortened by 277.5 min, comparing with pure water. A study on the characteristics of CO₂ hydrate formation in different types of nanofluids found that the induction time of hydrate formation in copper oxide nanofluids was the shortest, only 179 min. There is an optimal concentration of CO₂ hydrate promotion with copper oxide nanofluids. The gas consumption of CO₂ hydrate increases firstly and then decreases with the increment in the mass fraction of copper oxide nanofluids. There are great differences in the morphological images of CO₂ hydrate formation in different nanofluids.

Key words: carbon dioxide hydrate, nanofluids, mass transfer, kinetics, morphology

摘要：

气体水合物技术在海水淡化、水合物蓄冷、CO₂封存等领域有着广阔的应用前景，水合物快速生成是制约水合物技术应用的关键问题之一。利用自主搭建的CO₂水合物可视化生成实验装置进行了纳米流体中CO₂水合物生成特性的实验研究，分析了纳米粒子对CO₂水合物生成特性的影响。结果表明，与纯水相比，纳米流体体系中气体消耗量增加了2.17 mmol/mol，且诱导时间缩短了277.5 min。对不同种类的纳米流体中CO₂水合物生成特性的研究发现，氧化铜纳米流体中水合物生成的诱导时间最短，只有179 min。氧化铜纳米流体对CO₂水合物的促进存在一个最佳浓度，CO₂水合物耗气量随着氧化铜纳米流体质量分数的增加先增加后减少。不同种类的纳米流体中CO₂水合物生成过程中形态学图像存在较大差异。

关键词: CO₂水合物, 纳米流体, 传质, 动力学, 形态学