乙酸甲酯反應蒸餾塔之控制架構研究

Study of Control Structures for Methyl Acetate Reactive Distillation Columns

林宥任(Yo-Jen Lin)

指導教授 ： 林顯聖

國立臺北科技大學/工程學院/化學工程研究所/碩士(2011年)

摘要

反應蒸餾為一種將化學反應和物質分離結合在同一單元的技術，具有提高轉化率、增加經濟效益等優點。本研究以電腦模擬出一座以乙酸和甲醇為原料進行酯化反應產生乙酸甲酯和水之反應蒸餾塔，並比較二種不同類型的溫度控制架構，一為操作回流比及再沸槽加熱量來控制蒸餾板溫度，另一為操作雙股進料的莫耳流量來控制蒸餾板溫度，觀察在擾動下，何種架構有較好的控制表現。

模擬程式是以微軟 Visual Basic.NET 程式語言做為開發工具，以逐板計算的方式，依質量帄衡、相帄衡、能量帄衡求出每個紀錄時間之各板濃度、溫度等數據，並加入塔頂及塔底溫度控制器以達到控制產物濃度的目的，構成一完整的反應蒸餾塔模擬程式。

由模擬結果得知，二種架構面對擾動時有明顯不同的控制效果，在進料濃度改變下，以操作雙股進料量的控制架構會有較快的穩定時間，而操作回流比及再沸槽加熱量在進料溫度改變的擾動有較好的控制效果。

關鍵字

反應蒸餾 ； 動態模擬 ； 乙酸甲酯

並列摘要

Reactive distillation is a technique of combining reaction and separation in a single unit. It offers several advantages such as increasing conversion and economic potential. The purpose of the research is to simulate the synthesis of methyl acetate for reactive distillation column and compare the effectiveness of two different types of two temperature control structures. The first structure is that two tray temperatures in the column are controlled by manipulating reflux ratio and reboiler duty, and the second structure is that two tray temperatures are controlled by manipulating two fresh feed streams.

In this simulation program, Microsoft Visual Basic.NET was used as a developing tool. Develop the program with solving the mass balance, energy balance and phase
equilibrium equations and then construct them to be a series of subroutine models. Two temperature controllers were used to achieve the purpose of maintaining product quality.

From simulation results, the two structures have different control effectiveness. The first structure provides fast steady state time in the face of feed temperature change,
and the second structure works well in the face of feed composition change.

並列關鍵字

Reactive Distillation ； Dynamic simulation ； Methyl acetate

參考文獻

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