本論文中以Aspen Plus 模擬軟體建立水轉移反應系統數學模式，並與文獻實驗數據確認其準確度。水轉移反應器結構分成單一及兩顆水轉移反應系統來探討。根據水轉移反應模式，最適化問題為改變反應器進口溫度、進料組成及一氧化碳轉化率之最小水轉移反應器體積，燃料處理系統出口氫氣流量需要滿足2.2 kW之質子交換膜燃料電池使用，一氧化碳濃度限制在20 ppm。結果顯示當一氧化碳轉化率超過平衡轉化率時，含有熱交換器之兩顆水轉移反應系統之反應系統體積會大幅減少。從建立出來之設計通則可以快速決定水轉移反應系統流程。由靈敏度分析可以得到水轉移反應系統控制架構。操作度分析結果顯示當氫氣流量改變，單一水轉移反應系統操作範圍會比兩顆水轉移反應系統來的大，兩顆水轉移反應系統之操作度因為進口一氧化碳濃度增加而減少。 In this work, Aspen plus simulation software were used to develop a model to describe water gas shift (WGS) reactor systems which validated with experimental data. The WGS reactor structures, single and two, were investigated. Based on the WGS reactor systems model, optimization problem was formulated and performed to minimize the reactor volume by varying reactor inlet temperatures and feed compositions and CO conversion while maintaining the hydrogen flow rate (2.2 kW PEMFC used) and CO concentration constraint 20 ppm. The results show that two WGS reactors in series systems with intercoolers can largely reduce the reaction volume when CO conversion exceeded equilibrium conversion.Then, design heuristic was built to provide a quick determination of WGS reactor system flowsheet. After sensitivity analysis was made, control structures are explored here.The result shows single WGS reactor system has larger operability range than two WGS reactors in series during hydrogen throughput change. Operability range of two WGS reactors in series systems was reduced by an increasing inlet CO composition.