套管型薄膜二氧化碳吸收系統的解析解與實驗之研究

Conjugated Mass Transfer in Membrane Gas Absorption through a Concentric Circular Gas-Liquid Contactor

劉勁斖(Jing-Wei Liou)

指導教授 ： 何啟東

淡江大學/工學院/化學工程與材料工程學系碩士班/碩士(2016年)

https://doi.org/10.6846/TKU.2016.00575

摘要

本研究主要是探討以套管型模組應用在薄膜氣體吸收系統之解析解與實驗之驗證。針對套管型薄膜模組的部份，建立其速度分佈式及邊界條件。而在薄膜氣體吸收系統中，氣體溶質於氣、液兩相內之質傳屬於共軛格拉茲問題，利用正交性質展開法建立二維濃度分佈式，並配合分離變數法及級數展開可求得系統之解析解，且利用乙醇胺之化性，建構二氧化碳/乙醇胺之薄膜吸收系統，針對套管型模組系統之實驗操作，並建構數學理論的研究，也進一步推導出氣體溶質在氣-液薄膜接觸器內，於氣、液兩相中之平均濃度、質傳係數、吸收速率及吸收效率等物理量之數學表示式。 以本文所建構之理論為基礎，改變氣、液兩相之進料流量與混合氣體進料的濃度，對二氧化碳之化學吸收作廣泛的討論，並且配合實驗分析結果印證理論分析之準確性，研究之主要價值在於無需經過冗長費時的實驗即可求得整個吸收系統之質傳係數及氣體溶質的二維濃度分佈式，進一步可討論各種變因對吸收效率的影響。

關鍵字

套管型薄膜模組 ； 薄膜氣體吸收 ； 共軛格拉茲問題 ； 乙醇胺

並列摘要

The device performance of the membrane gas absorption system was investigated theoretically and experimentally in the present study. A mathematical formulation for a membrane gas absorption system was developed in a concentric circular gas–liquid membrane contactor that independently regulates gas and liquid flow streams. Chemical absorption of carbon dioxide by amine was carried out and illustrated to validate the theoretical predictions. The analytical solutions of mathematical formulations for such a conjugated Graetz problem were solved using the orthogonal expansion technique extended in power series. The absorption efficiency was calculated with the absorbent flow rate, gas feed flow rate and carbon dioxide concentration in the gas feed as parameters. The theoretical predictions show that the effect of the initial carbon dioxide concentration in the gas feed on the absorption efficiency is more significant. The influences of operating and design parameters on the absorption efficiency and total absorption rate are also discussed.

並列關鍵字

Gas absorption ； Concentric Circular ； Membrane contactor ； Conjugated Graetz problem

參考文獻

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