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[1]谢振强,李清平,杨硕,等.四氢呋喃水合物结晶及其浆液流变特性[J].油气储运,2024,43(09):1-12.
　XIE Zhenqiang,LI Qingping,YANG Shuo,et al.Study on crystallization and rheology of tetrahydrofuran hydrate[J].Oil & Gas Storage and Transportation,2024,43(09):1-12.
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四氢呋喃水合物结晶及其浆液流变特性

《油气储运》[ISSN:1000-8241/CN:13-1093/TE] 卷: 43 期数: 2024年09期 页码: 1-12 栏目: 出版日期: 2024-09-25
Title:
Study on crystallization and rheology of tetrahydrofuran hydrate
作者:
谢振强; 李清平; 杨硕; 姚海元; 秦蕊
Author(s):
XIE Zhenqiang; LI Qingping; YANG Shuo; YAO Haiyuan; QIN Rui
关键词:
四氢呋喃水合物; 偏光显微; 结晶生长; 浆液; 黏度
Keywords:
tetrahydrofuran hydrate;  polarizing microscope;  crystal growth;  slurry;  viscosity
分类号:
TE832
文献标志码:
A
摘要:
【目的】水合物浆液输送可有效节约药剂使用成本，有望成为一种安全经济高效的天然气海管运输模式，目前研究多为限定形状的水合物生成和水合物浆液流变性的实验研究，水合物浆液自发结晶和流动剪切下的结晶研究较少；而结晶是影响水合物浆液流变性的关键因素之一，对浆液中水合物结晶生长的研究有助于深入分析和预测海管的流动状态，对海管流动安全保障具有重要意义。【方法】首先通过理论分析了四氢呋喃水合物自发结晶过程，并通过偏光显微实验验证了该理论；进而使用高精度流变仪探究动态剪切作用对结晶生长特性的改变及剪切速率、降温速率等因素对水合物浆液流变性的影响。【结果】静态原位四氢呋喃水合物以棒状结晶生长，晶体的轴向生长速率大于径向生长速率；剪切作用使四氢呋喃水合物析晶数量增多、单晶尺寸减小，同时促进棒状晶转变为块状晶。浆液黏度随剪切速率增大呈指数型下降，随体系降温速率增大先快速增加后达到稳定，随四氢呋喃质量分数的提高而快速上升。【结论】四氢呋喃水合物棒状晶端部更小的界面能与更大的温度梯度促进晶体轴向生长，而剪切作用会强制改变晶间方位，促使棒状晶团簇形成块状晶。研究结果可为流动体系水合物生成及水合物浆液输送等相关研究提供参考。
Abstract:
[Objective] Hydrate slurry transportation can effectively save the cost of chemical agents, and is expected to become a safe, economic and efficient transportation mode of natural gas pipeline. At present, most of the studies are focused on the formation of hydrate with limited shape and the rheological properties of hydrate slurry, while there are few researches on spontaneous crystallization of hydrate slurry and crystallization under flow shear. Crystallization is one of the key factors affecting the rheology of hydrate slurry. The study on the growth of hydrate crystal in slurry is helpful to analyze and predict the flow state of sea pipe, which is of great significance to ensure the flow safety of sea pipe. [Methods] Firstly, the spontaneous crystallization process of tetrahydrofuran hydrate was analyzed theoretically, and the theory was verified by polarizing microscope experiment. The effect of dynamic shear on crystal growth and the effect of shear rate and cooling rate on rheological properties of hydrate slurry were investigated by using high precision rheometer. [Results] Static in situ tetrahydrofuran hydrate grows as rod crystals, and the axial growth rate of the crystals is higher than that of the radial growth rate. The shear effect increases the number of crystallization of tetrahydrofuran hydrate, decreases the size of single crystals, and promotes the transformation of rod-like crystals into massive crystals. The viscosity of the slurry decreased exponentially with the increase of shear rate, increased rapidly with the increase of cooling rate and then reached a stable level, and increased rapidly with the increase of tetrahydrofuran mass fraction. [Conclusions] The smaller interface and larger temperature gradient at the end of THF rod-like crystal can promote the axial growth of the crystal, and the shear force changes the intercrystalline orientation and promotes the formation of the rod-like crystal clusters into massive crystals. The results can provide reference for hydrate formation and hydrate slurry transport in flowing system.

相似文献/References:

[1]谢振强,李清平,杨硕,等.四氢呋喃水合物结晶及其浆液流变特性[J].油气储运,2024,43(11):1277.[doi:10.6047/j.issn.1000-8241.2024.11.009]
　XIE Zhenqiang,LI Qingping,YANG Shuo,et al.Study on crystallization of tetrahydrofuran hydrate and rheological properties of its slurry[J].Oil & Gas Storage and Transportation,2024,43(09):1277.[doi:10.6047/j.issn.1000-8241.2024.11.009]

更新日期/Last Update: 2024-07-17