以變壓吸附法分離汙染空氣中氧化亞氮之模擬

張喬凱(Chiao-kai Chang)

指導教授 ： 周正堂

國立中央大學/工學院/化學工程與材料工程學系/碩士(2014年)

摘要

隨著經濟蓬勃發展的同時，工業也日益發達，工業廢氣的排放也已經成為備受關注的議題。俗稱「笑氣」的氧化亞氮(N2O)是一種溫室氣體，同時也是化學工廠所排放的廢氣之一。當工廠在地面上發生廢氣洩漏時，將會需要專人在第一時間到場察看。因此，在車內設置一套可攜式汙染物捕獲裝置，用以捕捉汙染物並產生乾淨的氣體供隨車人員呼吸使用，將可確保處理人員的人身安全。
變壓吸附法(Pressure Swing Adsorption, PSA)是一種分離氣體混合物的程序，根據不同氣體成份對吸附劑吸附能力的不同，進而利用吸附選擇性的高低來篩選氣體，再搭配高壓吸附、低壓脫附的特性分離氣體混合物。
本模擬研究雙塔八步驟變壓吸附程序，所使用的吸附劑為商用吸附劑5A沸石，以10%氧化亞氮、71.1%氮氣及18.9%氧氣作為進料組成。此研究目的為將氧化亞氮分離至50 ppm以下，並產生氧氣濃度略高於空氣組成的新鮮空氣，同時使濃縮過後的氧化亞氮之回收率達到幾近100%。藉由探討不同操作變因如吸附塔塔長、進料壓力、真空壓力以及各步驟時間，尋求最佳化的分離操作條件。

關鍵字

變壓吸附 ； 分離氧化亞氮 ； 5A沸石 ； 笑氣

並列摘要

The industry prospers as the economy thrives. The emission of industrial waste gases has been a growing concern. Nitrous oxide (N2O), also known as ‘laughing gas’, is not only a kind of greenhouse gas, but also one of the waste gases emitted from chemical plants. When there are waste-gas spills above the ground, it is necessary for professional personnel to handle it on site instantly. Therefore, to ensure their safety, setting a portable, pollutant-capturing device in car will be a suitable way. Apart from capturing air pollutants, this device will also provide clean air to passengers.
Pressure Swing Adsorption (PSA) is a process to separate gas mixtures. Based on adsorption capability, selectivity, and the property that adsorbent adsorbs at high pressure and desorbs at low pressure, we can achieve the goal of separating gas mixtures.
In the simulation, a dual-bed eight-step PSA process is studied. The adsorbent is commercialized 5A zeolite. The feed composition is 10% N2O, 71.1% N2 and 18.9% O2. The oxygen concentration in the effluent gas should be slightly higher than air, with the concentration of nitrous oxide being less than 50 ppm. The recovery of concentrated nitrous oxide should be as high as nearly 100%. The optimal operating condition can be obtained by assessing different operating variables such as bed length, feed pressure, vacuum pressure, and the time of each step.

並列關鍵字

Pressure Swing Adsorption ； nitrous oxide seperation ； 5A zeolite ； laughing gas

參考文獻

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