以變壓吸附法分離汙染空氣中氧化亞氮之實驗

林滿豪(Man-hau Lin)

指導教授 ： 周正堂 ； 楊閎舜

國立中央大學/工學院/化學工程與材料工程學系/碩士(2015年)

摘要

隨著工業的發達，因為工廠廢氣排放所造成環境的影響日益受到重視，如何處理這些廢氣使其對環境的危害減小也是現今的重要議題。
氧化亞氮(N2O)俗稱笑氣，常在化學工廠的運作中產生，為一種溫室氣體，長期吸入對人體有害。但若能對其排放做減量或捕獲，便能減少危害。
變壓吸附法(Pressure Swing Adsorption，PSA)是一種利用吸附劑對不同氣體的吸附能力不同來分離混合氣的方法。並因為高壓吸附、低壓脫附的特性，可選用合適的步驟程序來達到期望的分離效果。
本研究先以微量天平(Micro-Balance Thermo D-200)量測UOP 5A沸石吸附劑分別對氧化亞氮、氧氣、氮氣之等溫平衡吸附曲線(isotherm)。接著以單塔進行貫流曲線與脫附曲線實驗，並改變進料壓力及流速，觀察其影響。最後以變壓吸附法分離氣體混合物。實驗中使用進料組成為10%氧化亞氮、18.9%氧氣、71.1%氮氣之混合氣，藉由不同的操作變因(進料壓力、各步驟時間、塔內溫度)，探討操作條件的不同對混合氣分離程序的影響，以期能對含有氧化亞氮的廢氣做初步的處理。

關鍵字

變壓吸附 ； 氣體分離 ； 氧化亞氮

並列摘要

With the development of industry, the environmental impact caused by plant emissions has become more seriously. It is also an important issue to deal with exhaust gas for reducing damage.
Nitrous oxide (N2O), known as laughing gas, is one of the factory emissions and a kind of greenhouse gases. Nitrous oxide will also harm the health, if someone breathes it frequently. So cutting down factory emissions of nitrous oxide is the goal of the study.
Pressure Swing Adsorption (PSA) is a process which can separate gas mixtures because adsorbates have different adsorption capability toward adsorbent. Based on the property of adsorption at high pressure and desorption at low pressure, we can choose the appropriate processes to achieve the desired separation.
First, this study obtained adsorption equilibrium data of pure N2O, O2 and N2 on UOP zeolite 5A by using Micro-Balance Thermo D-200. Then, breakthrough experiments were performed with single column in different operating conditions (feed pressure and feed flow rate) to observe their influence. In the end of the study, we separated gas mixtures by single-bed four-step PSA process. The feed compositions are 10% N2O, 18.9% O2 and 71.1% N2. The influence of operation variables were obtained by assessing different operating conditions. In other to study how to treat the exhaust gas comprising nitrous oxide.

並列關鍵字

Pressure Swing Adsorption ； gas separation ； nitrous oxide

參考文獻

[25] 張喬凱, 以變壓吸附法分離汙染空氣中氧化亞氮之模擬, 國立中央大學，碩士論文, 民國103年.

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