反應蒸餾塔之概念性設計:相對揮發度排序之影響

Conceptual Design of Reactive Distillation:Effects of Relative Volatilities Ranking

童士哲(Shih-Tse Tung)

指導教授 ： 余政靖

國立臺灣大學/工學院/化學工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.01401

摘要

多功程序在程序強化中是相當重要之一環，而多功程序中最主要例子為反應性蒸餾。過去10年的研究主要強調可行性分析、設計或控制方式探討。但針對相同或不同系統（如乙酸乙酯與乙酸丁酯），文獻上顯示著相當不同的程序架構，所謂程序架構在此指的是反應蒸餾塔中反應段與分離段之相對位置。在設計上，缺乏一系統化的整體概念性設計的步驟。因此，此研究目的希望藉由理想系統模擬歸納出一設計流程來決定程序架構。由於各種真實系統有其複雜性，因此使用理想反應系統來探討各種相對揮發度排序不同所對應之程序架構。在此考慮一可逆放熱反應A+B=C+D之四成份系統，而這四種組成有著所有可能排列的相對揮發度。根據相對揮發度之大小不同，會產生24（4!）種排列方式。若以反應物（A/B）與產物（C/D）作為分類基準，可將其簡化為6種組合。針對這些組合，我們將以年總成本（TAC）為考量進行最適設計產生最佳之程序架構，而結果顯示相對揮發度的排序在反應蒸餾塔架構扮演一個非常重要的角色，其年總成本從最佳的排序（兩產物分別為最輕與最重之成份）至最劣的排序（兩反應物分別為最輕與最重之成份）
將近增加了7倍。最後將發表概念性設計的經驗法則，藉以闡明相對揮發度排序與年總成本之間的關連性。

關鍵字

反應蒸餾 ； 程序架構 ； 相對揮發度 ； 概念性設計

並列摘要

Multifunctional process unit is an important element in process intensification and reactive distillation is one of the most common examples Despite recent progress in understanding the feasibility, design, and, in some cases, control of reactive distillation, conceptual design of reactive distillation is still carried out in an ad hoc manner and the process flowsheet seems to vary from case to case. Even for the same process (e.g., ethyl acetate and butyl acetate), literature examples also show several different process configurations. By process configuration, we mean the relative position of the reactive zone, and separation sections. In other words, a systematic design procedure which is capable of covering a wide range of system parameters is lacking. The objective of this work is aimed to provide a systematic design procedure to determine the process configuration. Instead of investigating real chemical systems, ideal chemical reaction systems with different relative volatility rankings will be studied. This provides a gradual transition as the reaction and separation properties change. The reaction considered is a reversible reaction,A+B=C+D, and this constitutes a quaternary system with 24 (4!) possible relative volatility arrangements. These 24 systems can further be grouped into six categories according to the ranking of relative volatilities of reactants and products. The likely process configurations will be explored and design will be optimized based on the total annual cost (TAC). The results clearly indicate that the relative volatility rankings play a dominant role in the reactive distillation configuration and the TAC varies by a factor of ~7 as we move from the most favorable case (reactants are intermediate keys) to the least favorable relative volatility ranking (products are intermediate keys). Finally, heuristics are given to correlate the relative volatility ranking to the total annual cost.

並列關鍵字

reactive distillation ； process configuration ； relative volatility ； conceptual design

參考文獻

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