在本研究中，開發了新型乙醇蒸汽重組（ESR）觸媒層管之設計，並以數值模擬分析其對製氫的影響。另外，利用最佳化方法評估在結合ESR和水氣變換反應（WGSR）系統中WGSR觸媒層管之間的最佳相對角度，得出對於降低一氧化碳及提升氫氣產率最好的條件。該研究分為兩個部分，如下所述。
在本研究的第一部分為開發具有穿流式的觸媒層管的新設計，其特點是觸媒用量較低，成本低。通過計算流體動力學（CFD）模型對新型觸媒層管系統進行模擬。通過改變觸媒層厚度與管徑比，管徑與通道寬度比、水醇比以及管數來評估四個參數對乙醇轉化率和氫氣產率的影響。結果顯示，提高觸媒層厚度與管徑比可以有效提高乙醇轉化率和氫氣產率，在當該值等於0.33時，可以獲得100％的轉化率。而管直徑與通道寬度的比例越大，氣時流速越低，從而導致觸媒層管系統的性能更好（乙醇轉化率平均提高130％）。另外，增加管數具有提高乙醇轉化率的作用，並且在使用四個管時可達到97％的轉化率。
在第二部分中，為了降低ESR觸媒層管反應器中所產生的高CO濃度，對單觸媒層管系統後方加入水氣轉移反應(WGSR)系統進行研究。結果顯示，在適合ESR的溫度範圍內，低溫較有利於該系統製氫，並發現對於此系統之最佳的水醇比為3。另外，發現管徑的變化比改變觸媒厚度具有更好的效率，因為可以更低的觸媒成本（降低33％）降低相同的CO濃度。最後，利用兩階段最佳化方式，第一階段的參數掃描進行大範圍搜尋目標函數，第二階段接著採用二次近似的界限最佳化方法(BOBYQA)的人工智慧找尋WGSR觸媒管之間更進一步精確的的角度排列組合。結果顯示，優化後的管子排列在流場中分佈均勻，與單觸媒層管系統相比，可以減少38 %的一氧化碳。

In this study, numerical simulation was conducted to analyze the effects of a new ethanol steam reforming (ESR) catalytic tube system design on hydrogen production and CO reduction. The optimization method was also applied to evaluate the best relative angles between water gas shift reaction (WGSR) catalytic tubes in the combination of ESR and WGSR system. The study was divided into two parts.
In the first part of this research, a new design of the catalytic tube system with a crossflow configuration, featured by low catalyst usage with low cost, is developed in this study. The simulation of ESR by using a new catalytic system is conducted by the computational fluid dynamics (CFD) model. The effects of four parameters on ethanol conversion and H2 yield are evaluated by varying the catalyst thickness, the ratio of tube diameter to channel width, the molar ratio of steam to ethanol (S/E ratio), and the number of tubes. The results indicate that the enhancement of the ratio of catalyst thickness and tube diameter can effectively improve the ethanol conversion and H2 yield stemming from the diminish of gas hourly space velocity (GHSV) and can be obtained 100% conversion when the value equal to 0.33; the greater ratio of tube diameter to channel width also give the lower GHSV, resulting in better performance of the catalytic tube system (130 % improvement in ethanol conversion averagely). In addition, increasing the number of tubes has the ability to rise the ethanol conversion, and attain 97% conversion ratio when using four tubes.
In the second part of this research, In order to reduce the high CO concentration form the ESR catalytic layer tube reactor for further application, the ESR followed by WGSR in the single catalytic layer tube system is investigated. The result reports that the low temperature is conducive to the hydrogen production for this system and the optimal S/E ratio is found to be 3 which is the theoretical value that would create the highest hydrogen yield and CO reduction improvement. Furthermore, it is discovered that the changing of tube diameter is better than changing the catalyst thickness because the same CO reduction improvement can be attained with lower catalyst cost (33% off). Lastly, the optimization tool Bound Optimization by Quadratic Approximation (BOBYQA) is used for finding the best tubes arrangement. It can be observed that the tubes are evenly distributed in the flow after optimization, and the better performance in terms of H2 yield and CO reduction improvement (38%) can be achieved compared to the single catalytic layer tube system.

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