面對化石燃料短缺和氣候變遷的挑戰，實現碳中和的永續燃料已成為當前的重要 議題。氨因其碳中和的特性而受到關注，被認為是可整合於工業設備如燃氣渦輪機和 鍋爐等的可行選擇。然而，氨的燃燒特性，包括其緩慢的燃燒速度和難以點燃的特性， 帶來了複雜的挑戰。混合氨和碳氫化合物被視為潛在的解決方案，但這也增加了燃燒 動力學和氮氧化物排放的複雜性。儘管已有些許文獻提到了添加少量氨的相關研究， 但要更深入地了解高氨比例的影響，仍需要進一步的分析。
為此，本研究的主要目標在於分析氫氣(H2)、甲烷(CH4)、焦爐氣(COG)與 氨混合燃料的燃燒複雜性。通過嚴格的一維模擬和適當的反應機制，進行基礎特性分 析。研究考察了不同當量比和氨比例下各種燃料混合物的層流燃燒速度、絕熱火焰溫 度和氮氧化物排放等關鍵參數。結果顯示不同燃料具有顯著的差異，氫氣表現出優異 的燃燒速度和絕熱火焰溫度，但添加氨後表現有所下降。相反，COG 燃燒表現出氫氣 和甲烷特性的組合，添加氨後的變化程度也有所不同。重要的是，氮氧化物排放量在 特定的氨含量閾值處達到峰值，然後下降，主要貢獻途徑是 HNO 途徑。此外，本研究 還發現不同燃料在個別基礎參數上有獨特的擬合特性，提出了一種新的快速找到不同 氫與甲烷混氨特性的方法，適用於層流燃燒速度、絕熱火焰溫度和一氧化氮排放特性。 隨後，使用經驗公式針對實際燃燒爐進行三維模擬，以更貼近實際應用情況。三維模 擬顯示經驗公式在甲烷與氨的混合燃料排放預測中極具準確度，且所有混合燃料的一 氧化氮排放與一維模擬趨勢相符。總體而言，本研究對永續燃燒方法的進步做出了重 要貢獻，有助於積極應對氣候變遷挑戰。

Confronting fossil fuel depletion and climate change challenges, achieving carbon neutrality with sustainable fuels has become crucial. Ammonia, due to its carbon-neutral properties, has attracted attention as a viable option for integration into industrial equipment such as gas turbines and boilers. However, the combustion characteristics of ammonia, including its slow burning rate and difficulty in ignition, pose complex challenges. Mixing ammonia with hydrocarbons has been proposed as a potential solution, although it introduces complexities in combustion kinetics and nitrogen oxide emissions. While some literature exists on the addition of small amounts of ammonia, further analysis is required to understand the implications of higher ammonia proportions.
This study aims to elucidate the combustion complexities of hydrogen (H2), methane (CH4), COG and ammonia mixtures. Through rigorous one-dimensional simulations and appropriate reaction mechanisms, fundamental characteristics are analyzed. Various key parameters such as laminar burning velocity, adiabatic flame temperature, and nitrogen oxide emissions of different fuel mixtures are examined at different equivalence ratios and ammonia levels. Results indicate significant variations in combustion behavior among different fuels, with hydrogen exhibiting superior burning velocity and adiabatic flame temperature, albeit showing a decrease upon ammonia addition. Conversely, COG combustion demonstrates a combination of hydrogen and methane characteristics, with varying degrees of change upon ammonia addition. Importantly, nitrogen oxide emissions peak at specific ammonia content thresholds before decreasing, primarily through the HNO pathway. Furthermore, unique fitting properties are observed for different fuels on individual basis parameters, proposing a novel method for rapidly assessing the characteristics of methane and ammonia mixtures with ammonia, applicable to laminar burning velocity, adiabatic flame temperature, and nitrogen oxide emission characteristics. Subsequently, three-dimensional simulations of actual combustion furnaces are conducted using empirical formulas to better approximate real-world application scenarios. Three-dimensional simulations show that empirical formulas are highly accurate in predicting emissions for methane and hydrogen mixtures, with nitrogen oxide emissions of all mixtures aligning with one-dimensional simulation trends. Overall, this study makes significant contributions to advancing sustainable combustion methods, aiding proactive responses to the challenges of climate change.

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