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Measurements for Thermodynamics and Kinetics of Methane Hydrate in the Presence of Acetamide, Cyclopentanol and 1,3-Dioxane
No full text本研究延續採用先前已建立之高壓設備裝置，並利用等容溫度循環法量測甲烷水合物分解之熱力學三相相平衡曲線 (H-Lw-V)，以及等容先降溫後升壓之方法量測甲烷水合物生成之動力學實驗數據。本研究主要目的為探討不同添加劑對於甲烷水合物系統是否於熱力學與動力學上具有之促進或抑制效果。以增加未來天然氣水合物開發應用之經濟效益。
本研究選用添加劑為乙醯胺 (Acetamide)、環戊醇 (Cyclopentanol) 以及1,3-二氧六環 (1,3-Dioxane)。結果顯示當乙醯胺存在時，則使甲烷水合物相平衡曲線往低溫高壓移動，因此縮小水合物穩定形成的溫壓區域，表示乙醯胺為熱力學抑制劑，且此抑制效果亦隨著添加劑濃度增加而提升。添加30 wt% 乙醯胺，約可抑制8.7 K；當環戊醇或1,3-二氧六環存在時，使甲烷水合物相平衡曲線往高溫低壓移動，因此擴大水合物穩定形成的溫壓區域，表示環戊醇以及1,3-二氧六環為熱力學促進劑，且此促進效果隨著添加劑濃度增加而提升。當添加8 wt% 環戊醇，約可促進6.8 K。而添加20 wt% 1,3-二氧六環，約可促進13.7 K。將本研究所使用添加劑與其他文獻添加劑比較歸納，發現添加劑的幾何形狀與官能基會影響水合物穩定的溫壓區域。另外，以3.5 wt% 氯化鈉模擬海洋環境，進行添加劑鹽水系統的熱力學相平衡量測，鹽類存在具有熱力學相對抑制的效果。在水合物生成動力學部分，則針對二丙酮醇 (Diacetone Alcohol) 來進行實驗。實驗結果顯示，與純水系統相比，二丙酮醇的存在的確可縮短水合物生成所需的誘導時間，並加速水合物生成的初始速率，此外，亦由實驗結果發現，添加二丙酮醇會大幅提升水合物的生成量，達到動力學上促進的效果。另外，針對具有加速水合物生成效果的環戊醇以壓力為變因，固定溫度的方式進行動力學實驗，並以過飽和梯度視為實驗趨動力。In this study, an apparatus which can be operated at low temperature and high pressure conditions was set up to measure the hydrate-liquid water-vapor (H-Lw-V) three-phase dissociation conditions of methane hydrate in the presence of additives by employing the isochoric method. The certain additives to system of methane + water were investigated for their effects on the phase boundary of methane hydrate. Also, the kinetic behavior of methane hydrate was investigated in an isochoric system to see how factors (e.g. sub-cooling temperature, experimental pressure) would affect the formation kinetics of methane hydrate.
In this work, acetamide, cyclopentanol and 1,3-dioxane were chosen as additives. The addition of acetamide in methane hydrate system shifted hydrate phase boundaries to higher pressure and lower temperatureand thus the hydrate stability region was broadened, therefore it had a inhibition effect on the formation of methane hydrate. Furthermore, the inhibition effect increased when the concentration of Acetamide in hydrate system increased. With 30 wt% acetamide the equilibrium temperature decreases about 8.7 K at given pressure in comparison to that of pure water system. On the other hand, the results of adding cyclopentanol or 1,3-dioxane showed the promotion effect on the formation of methane hydrate. Similarly, the promotion effect increased when the concentration of cyclopentanol or 1,3-dioxane in hydrate system increased. With 8 wt% cyclopentanol, the equilibrium temperature increases about 6.8 K at given pressure in comparison to that of pure water system. With 20 wt% 1,3-dioxane, the equilibrium temperature increases about 13.7 K at given pressure in comparison to that of pure water system. In addition, 3.5 wt% NaCl(aq) was usedas brine solution to simulate the salinity of the seawater environment. The dissociation conditions of methane hydrate in brine were also measured in this study with the addition of acetamide, cyclopentanol and 1,3-doxane.
In the formation kinetics of methane hydrate, 4-Hydroxy-4-methyl-2-pentanone (Diacetone Alcohol) was chosen as additive. The results showed that diacetone alcohol could reduce the induction time in comparison to that of pure water system and the initial rate of hydrate formation was effectively increased by adding diacetone alcohol. In conclusion, diacetone alcohol was an effective kinetic promoter to form methane hydrate in this work. In addition, cyclopentanol seems that it could shorten the induction time needed for hydrate formation so cyclopentanol was chosen as additive to test new formation kinetics experiments.摘要 I
Abstract II
目錄 IV
表目錄 VII
圖目錄 IX
第一章緒論 1
1-1天然氣水合物簡介 2
1-2 氣體水合物型態結構 3
1-3氣體水合物的發展史 5
1-4天然氣水合物相關應用 6
1-4.1 抑制天然氣水合物的生成 7
1-4.2天然氣水合物的開採 9
1-4.3天然氣水合物研究的相關應用 10
1-5 研究動機與方向 13
第二章文獻回顧 15
2-1 相關理論 15
2-1.1 自由度計算 15
2-1.2水合物的相圖 17
2-1.3 水合物生成機制 19
2-1.4 記憶效應 20
2-2 相關研究 21
2-2.1 水合物熱力學相關研究 21
2-2.2 水合物生成動力學相關研究 22
2-2.3水合物結構之鑑定 23
第三章實驗裝置與方法 26
3-1 實驗藥品 26
3-2實驗設備 27
3-3實驗方法 28
3-3.1 甲烷水合物熱力學相平衡 28
3-3.2甲烷水合物生成動力學 29
3-4 實驗步驟 30
3-3.1 甲烷水合物熱力學相平衡 31
3-3.2甲烷水合物生成動力學 32
3-4實驗數據分析 33
3-4.1 甲烷水合物熱力學相平衡 33
3-4.2甲烷水合物生成動力學 34
第四章結果與討論 36
4-1 溫度循環流程之探討 36
4-2 甲烷水合物於純水系統的相平衡實驗量測 (對比實驗) 38
4-3甲烷水合物於添加劑系統的相平衡實驗量測 40
4-3.1添加劑的選用 40
4-3.2快速溫度循環 42
4-3.3添加劑初步測試與篩選 44
4-3.4 甲烷+純水+乙醯胺之水合物系統相平衡數據 45
4-3.5甲烷+純水+環戊醇之水合物系統相平衡數據 48
4-3.6甲烷+純水+1,3-二氧六環之水合物系統相平衡數據 51
4-3.7 甲烷+鹽水+添加劑之水合物系統相平衡數據 54
4-4動力學實驗方法與對比實驗 57
4-5甲烷水合物於添加劑系統的生成動力學實驗量測 (等容操作法) 60
4-5.1 甲烷+純水+二丙酮醇之水合物系統 60
4-5.2甲烷+純水+環戊醇之水合物系統 65
第五章結論 68
參考文獻 16
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No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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