由於近年來環保意識抬頭，為了降低溫室效應，各方學者積極發展潔淨的替代能源。在眾多選擇當中，氫氣擁有高能量密度，在使用上亦不會產生溫室氣體，是極具發展性的替代能源。本研究共分成兩個部分，第一部分是利用數值模擬探討在不同的氣時空速之下，瑞士捲反應器中之甲烷催化部分氧化反應的暫態過程與可用能回收率。其中以銠（Rh）觸媒進行催化，氧碳原子比設定為1.0。模擬結果顯示出當反應到達穩態時，擁有熱回收效應的的甲烷轉化率可超過80%，遠高於無熱回收的狀況。而且瑞士捲的可用能回收率在66%以上，由此可見瑞士捲之熱回收效能。
接著第二部分探討在不同的氣時空速與氧碳原子比下，瑞士捲反應器中的甲烷催化部分氧化反應之熵增。藉由熵分析，可以深入瞭解化學反應、熱傳和摩擦力這三種效應對熵增所造成的影響，以及熵增與產氫效率的關係。從結果可以發現化學反應為熵增的主要來源，相較之下摩擦力所造成的熵增是可忽略的。另外，所有效應的熵增量和氣時空速成正比，瑞士捲捲數的增加也會使熵增率提高，但是摩擦力在流道中造成的情況是例外的。在氧碳原子比為1.2時，單位甲烷之化學反應熵增率為最高。

Catalytic partial oxidation of methane (CPOM) is a promising method for hydrogen production with autothermal reaction. The present study will focus on two topics, with one on unsteady reaction characteristics, and the other on entropy generation of CPOM.
To figure out the unsteady reaction characteristics of CPOM in a Swiss-roll reactor along with heat recirculation, a numerical method is employed to simulate the transient reaction dynamics, with emphasis on energy recovery using exergy analysis. Three different gas hourly space velocities (GHSVs) of 5,000, 10,000 and 50,000 h-1 with the condition of atomic O/C ratio of 1 are considered. The predictions indicate that increasing GHSV substantially shortens the transient period of chemical reactions; however, it also reduces the methane conversion, as results of more reactants sent into the reactor and shorter residence time of the reactants in the catalyst bed. Within the investigated range of GHSV, the methane conversion with energy recovery at the steady state is larger than 80%, much higher than the reaction without heat recovery. The selectivities of H2 and CO in the product gas are always larger than 90%. The exergy recovery is in the range of 66-80%, implying that over two-third useful work contained in the product gas can be reused to preheat the reactants in the reactor, thereby enhancing the performance of CPOM.
By using the entropy analysis, the impact of chemical reactions, heat transfer and friction on entropy generation and the relation between entropy generation and hydrogen-producing efficiency have been investigated. Three important parameters of number of turns, GHSV and O/C ratio are in the ranges of 1-3, 10,000-50,000 h-1 and 0.8-1.4, respectively. The results show that the chemical reactions are the main sources of entropy generation, whereas the friction plays almost no part on entropy generation, compared to heat transfer and chemical reactions. The entropy generation rate is proportional to GHSV. It is larger when the number of turns is increased except the friction in channel. Furthermore, at O/C ratio=1.2, the maxima specific entropy generation rate from chemical reactions is exhibited.

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