氮氧化物(NOx)為燃燒過程中伴隨產生之污染物，是周界空氣的指標污染物之一，此外氮氧化物會於空氣中行光化學反應，為臭氧、PAN等衍生性污染物之前驅物，因此一直是我國於改善周界空氣品質時重點關注之污染物，針對其排放量之相關法規逐步加嚴。氮氧化物的防制設備中，較為廣泛運用者為選擇性觸媒還原法(SCR)，但對於規模較小的鍋爐之污染防制而言，其適用的煙氣溫度較高(250~350℃)，且操作成本也高，因此發展一成本較低，並適合於低溫下操作之脫硝技術為目前的需求。
氮氧化物因其水溶性低，無法像硫氧化物一般輕易地以濕式洗滌塔去除，臭氧氧化法便是透過臭氧將氮氧化物氧化為價數更高的N2O5、HNO3等易溶於水的物種後，搭配濕式洗滌塔達成去除煙氣中氮氧化物之目標。
本研究設計一PFR反應槽，並以NO氣體模擬燃燒廢氣，與臭氧一起注入槽中量測其反應過程之濃度變化，並整理各個可能參與反應過程的基本反應式(elementary reaction)，以數值方法計算各物種濃度隨時間的變化，並將理論值與實驗值進行比對，以此探討不同反應溫度、停留時間、O3/NO等條件對NOx去除效率之影響。
經流場模擬與實驗測試，本研究建置之反應槽可以正常順利運作，其測試結果之誤差約為15~20%。以本研究所建置之數值模型依實驗條件進行模擬，將模擬值與實測值比對，兩者之差異在誤差範圍內，顯示模擬之結果可信。而透過文獻回顧及模擬值可知，影響臭氧脫硝技術的關鍵為O3/NO之莫耳數比及反應溫度。反應開始時O3於不到1秒的時間內將NO氧化為NO2，隨後進行較慢的反應將NO2進一步氧化為NO3，NO3再與NO2結合形成N2O5，理論上O3/NO需大於1.5才能完全將NO轉為N2O5，反應完成速率則與O3濃度有關，O3越高反應速率越快，但最終殘留的O3也較多。操作溫度方面，反應溫度越高時N2O5、O3較易熱解，且系統中自由基之濃度上升，主導了反應進行，使得N2O5無法穩定存在，最終產物以NO2為主，導致去除效率不佳。
本研究之數值模型模擬結果顯示O3/NO = 1.5時於318 K下操作有最好的去除效率70.95 %；O3/NO = 2.0時於313 K下操作有最好的去除效率91.11 %；O3/NO = 2.5時於308 K下操作有最好的去除效率96.67 %。雖莫耳數比越高有越好的去除效率，但也伴隨著臭氧殘留的問題，在O3/NO = 2.5，反應溫度308 K的情境下最終臭氧殘留高達164ppm。

Nitrogen oxides (NOx) are pollutants generated during combustion. Besides being criteria pollutants, NOx undergo photochemical reactions, forming secondary pollutants like ozone and PAN. Consequently, NOx is a focus in efforts to improve air quality, leading to stricter emission regulations. Selective Catalytic Reduction (SCR) is widely used for NOx control but is less feasible for smaller boilers due to high temperature (250~350℃) and cost requirements. Thus, the goal of this study is to develop a low-cost, low-temperature denitrification technology.
Ozone oxidation deNOx technology oxidizes NOx into soluble species like N2O5 and HNO3, which can be removed using wet scrubbers. This study develop a numerical model to simulate the reactions of this technology. This study also designed and constructed a PFR reactor to conduct experiments. This setup not only verifies the results of numerical simulations but also allows for the investigation of actual reaction conditions. It investigates the effects of different reaction temperatures, and O3/NO ratios on NOx removal efficiency.
According to the experiments, the measured values align with the simulated values, indicating the reliability of the numerical simulation results. According to the simulation results, the key factors affecting ozone oxidation deNOx technology are the molar ratio of O3/NOx and reaction temperature. Optimal removal efficiencies are achieved with higher O3/NO ratios but also result in higher residual ozone. Simulation results show the best removal efficiency can reach up to 96.67% under conditions of O3/NO = 2.5 and a reaction temperature of 308 K.

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