天然氣水合物降壓分解實驗之數值模擬研究

Numercial Simulation of Gas Hydrate Dissociation in Lab-scale Depressurization Experiment

楊嘉勝(J.S. Yang) ； 吳政岳(C. Y. Wu) ； 謝秉志(B.Z. Hsieh)

《鑛冶：中國鑛冶工程學會會刊》 62卷1期 (2018/03) Pp. 31-43

https://doi.org/10.30069/MM.201803_62(1).0004

摘要

本研究的目的為利用數值模擬建立二維圓柱模型模擬水合物在實驗室尺度下的降壓分解實驗，並探討流動特性與水合物反應參數對於水合物分解行為的影響。本研究仿照國外水合物降壓分解實驗案例，建立數值模擬模型，透過敏感度調查不確定參數對水合物分解行為的影響，再經過調諧找出最佳參數組合。研究結果顯示：(1)水合物的活化能、反應速率常數對反應速率的影響劇烈且為控制溫度變化的主要因子；相對滲透率、不可移棲氣飽和度影響氣體流動行為，控制氣產率高峰值與最終累積氣產量。(2)將最佳擬合結果與前人模擬結果比較發現本研究的溫度及氣產率曲線較平滑且吻合。(3)將此模擬模型應用於台灣科技大學團隊的水合物分解實驗中得到相同的曲線趨勢。

關鍵字

天然氣水合物 ； 降壓分解 ； 實驗 ； 數值模擬

並列摘要

The purpose of this study was to develop a two-dimensional axisymmetric numerical model to simulate the gas hydrate dissociation in a lab-scale depressurization experiment. This work also investigated the effects of the flow characteristics and hydrate reaction parameters on the gas hydrate dissociation. We performed a sensitive analysis of the flow properties and hydrate reaction parameters to understand how these parameters affect the dissociation behavior. The numerical simulation runs were done to match the experimental data published in literature. The major findings from this study were: (1) Hydrate reaction parameters such as activation energy and intrinsic rate constant have a significant effect on the dissociation rate. And the flow parameters, e.g., relative permeability and irreducible gas saturation, are crucial for gas production. (2) This work showed smoother results in the temperature and gas production profile. (3) Our simulation module was verified using the experiment data provided by National Taiwan University of Science and Technology.

並列關鍵字

Gas hydrate ； Depressurization ； Experiment ； Numerical simulation