| 摘要: | 二十一世紀是個能源將逐漸匱乏的世紀，仔細分析美日歐等先進國家過去對其未來能源供應和能源科技研究之規劃佈局，可知均已重回到以節能及保護自然資源和環境的方向。從工業革命到現在，全世界所有能源的取得和應用(含電力、運輸載具、工業爐、瓦斯爐具等等)，仍以燃燒為最主要的方法，平均80%以上，我國和美國等許多國家並幾達約90%，這情形預計將延續到未來數十年。儘管目前絕大部分內燃機和各式燃燒器其效率均不高，尚有許多改善之空間，但因碳氫燃料每公斤的儲能密度約45 百萬焦耳(近百倍於目前鋰電池的儲能密度)，使碳氫燃料(煤、石油、天然氣等)即使在價格高漲的今日，仍是最具經濟競爭力的燃料，在可見的未來(甚至將長達數十年)，仍將如是。可是，燃燒所產生之環境空污問題、CO2等溫室效應氣體和全球氣候變遷等問題，已嚴重影響地球生態系統。隨著社會對環境保護有越來越高的要求，將促使各國政府必須全力研發能源科技，以提供解決問題的選擇方案。是故，本計畫針對節約能源科技領域，提出一低氮氧化物燃燒器和氫燃燒器之實作研究，除了進行低碳燃料(天然氣)加氫燃燒技術之開發與應用，並著手同步研發純氫燃燒技術，發展無碳潔淨氫能利用技術，來達成節能減碳之目的。以現今國際燃燒領域中之先進燃燒方法，即貧油預混紊流燃燒科技，結合漩渦流穩焰等前瞻設計概念，開發天然氣加氫燃燒技術和純氫燃燒新技術，並研發低於10 ppm之個位數氮氧化物燃燒器。因天然氣為所有碳氫化合物中具有最低碳氫比之燃料，且其熱值不低，約是同重量汽油之80%，故有助CO2減量，是今後20、30 年過渡到氫能源(或其他可能之能源)又要顧及溫室氣體減量之主要燃料。本計畫第一年度針對已發展多年且具成果之高效率天然氣加氫燃燒技術(代表作：Effects of Hydrogen or CO2 Additions, Equivalence Ratio, and Turbulent Straining on Turbulent Burning Velocities for Lean Premixed Methane Combustion”, Combustion and Flame, Vol. 153, No. 4, pp. 510-524, 2008)，提出應用弱漩渦流穩定噴流預混紊焰機制之實驗研究，方法為在燃燒器噴嘴出口前端設置一弱漩渦產生器，由四支特殊斜角設計之切邊噴嘴所構成，所產生之環狀渦流可在出口流場產生一均勻徑向壓力梯度，進而產生穩定預混紊焰之效果，並達到開發個位數氮氧化物燃燒器的目標。目前工作均按既定進度執行，已獲初步成果。99年度(第二年度)擬利用此弱漩渦噴流預混燃燒器，以氫完全取代甲烷，發展純氫燃燒器。本計畫所研發之天然氣加氫燃燒技術結合低氮氧化物燃燒器，可應用於燃氣渦輪發電廠、工業鍋爐與焚化爐等，而氫能利用新技術(純氫燃燒器)將是未來無碳能源的重要選項之一，相當值得投入開發。 The 21st Century will be a century of energy shortage. When carefully analyzed the information of energy policy and science research and development from advanced countries (e.g., USA, Japan, Euro), one can know that the main strategy is back on how to save energy and protect natural resources and environment. Ever since the industry revolution to present, combustion is still the major means to provide the total energy consumption in the world from the electricity power generation sector to various transportation sectors to industrial furnaces and burners. Many countries, such as Taiwan and USA, nearly 90 % of total energy consumption is provided by fossil fuels. This situation is expected to continue for at least several decades. Even though most internal combustion engines and burners have rather low efficiencies that still need improvement, typical hydrocarbon fuels have roughly 100 times energy density (~ 45 MJ/kg) higher than that of modern lithium batteries (~ 0.5 MJ/kg) and thus fossil fuels even with prices up to US$140 per barrel are still the most competitive fuel in many aspects. But the real challenge by which mankind may face today is the global carbon problem, especially for the need of CO2 reduction due to the global climate change, how to promote the efficiency of using available energy resources (especially oils), develop the new energy technology, and achieve the clean energy goal have always been the main strategies by industrial nations. In the future, we shall face the problem of the energy shortage and the international pressure on demanding the reduction of green house gases (especially the reduction of CO2). Thus, the high-efficiency clean energy technology especially on the aspect of combustion is central to our country and its importance is crystal clear. This motivates the present proposal. How to reduce CO2 emissions or develop oil substitutes, such as the usage of methane fuel with very low molar ratio of carbon to hydrogen and the usage of hydrogen energy, is the goal of the present proposal. Thus, in the first year, we aim to develop high-efficiency, low-NOx combustion technologies, which are new energy saving technologies. We apply lean premixed turbulent combustion together with weakly swirling jet streams to develop a single-digit low-NOx burner and to establish high-efficiency natural gas doping with hydrogen combustion technology. The low-NOx burner has been designed and made. Experiments using methane and air mixtures doping with various percentages of hydrogen are currently conducting and preliminary results are obtained. In the second year (2010), the goal is to develop a pure hydrogen burner without carbon emission using pure hydrogen as a fuel in the aforementioned burner. These technologies can be applied to stationary power generation or automobile for cleaner burning having environmental advantages of CO2 reduction with very low-NOx emissions. 研究期間：9901 ~ 9912 |
