本研究使用一實驗室尺度燃燒器針對甲醇噴霧燃燒進行實驗研究，並且針對甲醇中水含量的多寡對火焰燃燒特性的影響。甲醇經濟廣為人知且被定義為使用甲醇作為能源載體，甲醇可以由廢棄物或生物質或者是透過捕捉回收的二氧化碳和水通過觸媒催化反應進行生產；但是製造甲醇的過程中會產生水，不僅如此，由於甲醇的親水性都會使甲醇中含有水分，因此需要額外的能量來去除甲醇混合物中的水以達到使用的標準。在本研究中，吾人分別研究了在空氣中以及在純氧燃燒系統中的甲醇噴霧燃燒並且探討了燃料中含水量對甲醇噴霧燃燒特性的影響，並評估甲醇混合物中含水量的上限。關於噴霧燃燒的燃燒效率，可以根據一氧化碳排放指數（EICO）進行估算。整體來說，甲醇中的水含量對火焰穩定性、排放和相對效率的影響皆在本研究中進行了詳細的描述並且提供幾個重要結論。了解甲醇的噴霧燃燒及其穩定性、排放和相對效率，將為進一步高效應用甲醇噴霧燃燒奠定學理的基礎。

The methanol spray combustion in the laboratory-scale combustor was experimentally studied in the present study, especially for the effect of the water content in methanol on the flame phenomena. The methanol economy is defined as using methanol as a means of energy carrier. It has been well known that methanol can be produced from waste and biomass or recycled carbon dioxide and water through the catalytic reaction. However, water is produced in the process of making methanol. Moreover, due to methanol's hydrophilic nature; hence, additional energy is required to remove the water from the methanol mixture.
In the present study, the spray combustion in ambient air and in the oxy-fuel system was separately examined. The effect of water content on the spray combustion characteristics of methanol spray was studied, and the upper limit of water contents in the methanol mixture was explored. For combustion efficiency, it can be estimated according to the emission index of CO (EICO). The effect of water content in methanol on flame stabilization, emissions, and relative efficiency is also evaluated. This research provides several important conclusions related to the methanol spray combustion in the air and the oxy-fuel combustion system. Understanding the spray combustion of methanol and its stabilization, emissions, and relative efficiency will serve as the basis for the further high-efficiency application.

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