發(fā)布時間：2018-04-04 05:25

  本文選題：臭氧　切入點：反應動力學　出處：《南昌大學》2017年碩士論文

【摘要】：臭氧是自然界最強的氧化劑之一,其應用領域不斷擴展,市場需求也不斷擴大。但臭氧產(chǎn)生效率仍然很低,極大的限制了其推廣應用。為提高產(chǎn)率降低能耗,本文立足于研究脈沖介質(zhì)阻擋放電臭氧產(chǎn)生過程的能量轉(zhuǎn)換及溫度依賴,通過編譯化學反應機理體系,并耦合質(zhì)量守恒方程、組分守恒方程、電子能量守恒方程以及能量守恒方程,建立合適的反應動力學模型,分別對干空氣(N_2-O_2)源和氧氣(O_2)源下脈沖放電臭氧發(fā)生過程進行分析。具體如下:(1)研究空氣源下氣體流量、壓力以及進口溫度對臭氧產(chǎn)生過程的影響,增大氣體流量,臭氧質(zhì)量濃度減小,臭氧產(chǎn)量和產(chǎn)率增大;增大氣體壓力或進口溫度,臭氧的質(zhì)量濃度、產(chǎn)量和產(chǎn)率都是減小的;隨著放電功率的增加,臭氧質(zhì)量濃度和產(chǎn)量都隨之增加并逐漸達到飽和,而臭氧產(chǎn)率先增大后減小。(2)臭氧發(fā)生過程中電子能量轉(zhuǎn)換為反應能,氣體溫度升高消耗的能量以及通過反應器壁傳遞的熱能,探究不同進口溫度下三種能量轉(zhuǎn)換率ηreaction,ηgas和ηloss隨比能的變化,空氣源時,增大比能,ηreaction先增加后減少,ηloss先減少后增加,而ηgas一直是增加趨勢。增大氣體進口溫度,ηreaction隨之緩慢減少,而ηloss和ηgas都隨之增加。氧氣源時,增大比能或氣體進口溫度,ηloss和ηgas都隨之增加,相應的ηreaction隨之減少。(3)通過敏感性和生成速率分析獲得各粒子反應路徑圖,并定量分析單個反應對粒子的敏感性系數(shù)和生成速率系數(shù)隨氣體平均溫度的變化,得到對粒子影響較大的反應途徑。干空氣源時對臭氧合成影響較大的粒子有O、O_2、O_2(1(35)g)、N_2(A)、NO、NO_2。N_2(A)有助于O原子產(chǎn)生,O_2(1(35)g)、NO、NO_2均會參與分解臭氧,臭氧主要合成反應O+O_2+O_2→O_2+O_3、O+O_2+N_2→N_2+O_3以及主要分解反應O+O_3→2O_2、e+O_3→e+O_2+O的生成速率隨著溫度的增加都是增加的;氧氣源時影響較大的粒子有O、O(1D)和O_2(b1∑)。O(1D)和O_2(b1∑)的存在都會加速臭氧分解。臭氧主要合成反應O+O_2+O_2→O_3+O_2、O+O_2+O_3→O_3+O_3以及主要分解反應O_3+O_3→O_2+O_2+O_2、O_3+O→O_2(b1∑)+O_2的生成速率隨著溫度的增加都是增加的。
[Abstract]:Ozone is one of the strongest oxidants in nature.However, ozone production efficiency is still very low, which greatly limits its application.In order to improve the yield and reduce energy consumption, the energy conversion and temperature dependence during the generation of pulsed dielectric barrier discharge ozone are studied in this paper. By compiling the chemical reaction mechanism system, the mass conservation equation and the component conservation equation are coupled.The electron energy conservation equation and the energy conservation equation are used to establish a suitable reaction kinetic model to analyze the generation process of the pulse discharge ozone under the dry air NSP _ 2-O _ 2) source and the oxygen O _ 2 / O _ 2 source, respectively.(1) to study the effects of gas flow, pressure and inlet temperature on the ozone production process under an air source, increase the gas flow rate, decrease the ozone mass concentration, increase the ozone production and yield, and increase the gas pressure or inlet temperature,The mass concentration, yield and yield of ozone decrease with the increase of discharge power.However, ozone production increases first and then decreases. 2) during ozone generation, electron energy is converted into reaction energy, energy consumed by gas temperature rising and heat energy transferred through reactor wall.The changes of three energy conversion rates 畏 reaction, 畏 gas and 畏 loss with specific energy at different inlet temperatures are investigated. When air source increases, 畏 reaction increases first and then decreases, 畏 loss decreases first and then increases, and 畏 gas always increases.As the inlet temperature of the gas increases, 畏 reaction decreases slowly, while 畏 loss and 畏 gas increase.When the oxygen source increases the specific energy or the inlet temperature of the gas, 畏 loss and 畏 gas increase, and the corresponding 畏 reaction decreases.The sensitivity coefficient and formation rate coefficient of a single reaction to particles vary with the average gas temperature, and the reaction path which has a great influence on the particle is obtained.The particles that have a greater impact on ozone synthesis in dry air sources are: O / O / S / O / S / O / S / T / T / T / N / O / T / T / O / O / T / O / O / O / T / O / O / O _ 2 / O _ O _ 2 / O _ O _ 2 / O _ 2O _ 2 / O _ O _ 2 / O _ 2O _ 2 / O _ O _ 2 / O _ O _ 2 / O _ O _ 2 / O _ O _ 2O _The main synthesis reaction of ozone, O / O / O / O / O / O / T / O / O / O / T / T / O / O / T / O / O / T / O / O / O / O / O / O / O / O / O / O / O / O / O / O / T / O / O / O / O / O / O / O / O / O / O / O / O / O / O / O / O / O / O / O / OThe existence of the most influential particles in the oxygen source, such as O _ 2O _ 1D) and O_2(b1 鈭，

本文編號：1708558