由於生物緩衝劑和水的親和性高但和有機溶劑的親和性極低，因此於有機水溶液中加入生物緩衝劑後，會大幅改變水與有機溶劑之間的相對揮發度，進而誘發液液分相的現象發生，此現象稱為緩衝析出 (buffering-out)。於正丙醇脫水程序中加入3-[4-(2-hydroxyethyl) -1-piperazinyl]-propanesulfonic acid (EPPS)作為共沸劑為例，進行了三個不同概念性設計的模擬，並利用產物皆達規格的Case C (萃取法)來探討三個不同設計變數所帶來的效應對能耗之影響，其中以分相槽的組成對能耗的影響最為劇烈。因為未熱整合前的能耗偏高，因此透過外部熱整合來降低其能耗，熱整合後能耗約可節省41 %。動態方面透過溫度分佈圖找出溫度變化最大的板，接著在適當的控制架構及策略下，去探討熱整合前後的動態響應，而從模擬結果可以看到所提出的控制策略能夠有效地處理進料流量及進料組成的擾動。

The affinity of EPPS/Water is much higher than EPPS/organic solvent, so adding biological buffers in organic aqueous solution will change the relative volatility between water and organic solvent significantly, and then induce the liquid-liquid phase separation phenomenon, it is so called the buffering-out phenomenon.
1-propanol (NPA) - water dehydration process by using 3-[4-(2-hydroxyethyl)-1-piperazinyl]-propanesulfonic acid (EPPS) as entrainer is illustrated as an example to simulate three different configurations in this study. it is found that the Case C configuration by using extraction approach can meet both products specification. And also, the influences on energy consumption of three kinds of effects are investigated in this thesis. As a result, the composition of decanter is the most influential factor on the total energy consumption. Furthermore, the external heat-integrated design is established for this process. It is found that 41 % energy reduction can be achieved after energy integration arrangement.
For the process dynamics, overall control strategy with/without heat integrated configurations also proposed and different variations in the throughput changes and also feed composition change are investigated. All processes are maintained at high product purity and have excellent responses.

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