第九章固定源氮氧化物污染控制 氮氧化物的性质及来源 燃烧过程中氮氧化物的形成机理 低氮氧化物燃烧技术 烟气脱硝技术
第九章 固定源氮氧化物污染控制 ➢ 氮氧化物的性质及来源 ➢ 燃烧过程中氮氧化物的形成机理 ➢ 低氮氧化物燃烧技术 ➢ 烟气脱硝技术
§9-1氮氧化物的性质及来源 、大气中氮氧化物的来源 N2O、NO、NQ、NO2、N2O4N2O5Nx N、N02为主要的大气污染物。 (1)自然来源 细菌对含氮有机物的分解、火山爆发、森林火灾等。 (2)人类活动 a.燃料燃烧(约90%) 95%以N形式存在,其余主要为NO2 b.化工过程;
§9-1 氮氧化物的性质及来源 NO、NO2为主要的大气污染物。 NOx 一、大气中氮氧化物的来源 N2O、NO、N2O3、NO2、N2O4、N2O5 （1）自然来源 细菌对含氮有机物的分解、火山爆发、森林火灾等。 （2）人类活动 a. 燃料燃烧（约90％）： 95％以NO形式存在，其余主要为NO2； b. 化工过程；
mosphere In the NO is oxidized to no, which then reacts wi No O2 NO HNO,. That can torm If we wish to prevent the D fine particles acid rain emission of NO x from fuel bustion we cannot capture it as a solid t All high-temperature Rain removes no from the because there are no insoluble processes, such as lightning atmosphere, mostly depositing N salts. Instead we must trikes and combustion form it in the oceans convert it back to N, gas and No by reacting atmospheric N, Microorganisms in the oceans put that back in the and O,. Fossil fuel combustion return it to the atmosphere. atmosphere of gen NH, or n2 n the fuel to no or no jointly called NOx Land (crust and mantl Fossil fuels(gas, oil, coal)are Oceans formed by slow transformation 篷 In the crust and mantle there are no common minerals of the bodies of plants and containing much nitrogen chemically bound nitrogen, believed to be formed from the All nitrates are very water bodies of microorganisms soluble, so that if we deposit a nitrate in the ground, it All plants and animals need small amounts dissolves of n in their diet, to form proteins. Some and plants(legumes)ca use atmospheric nitrogen. Most plants and animals cannot, and rely on fixed nitroge either from lightning strikes or from fertilizer factories Principal fiows of N in the environment. as influenced by humans. The atmosphere is about 78% N2. which is mostly inert and remains in the atmosphere. This figure shows only how the oxidized and reduced compounds of nitrogen are formed, move through the environment, and are converted back to relatively inert N
二、氮氧化物的性质 N0:无色、无味、无臭,微溶于水,在大气中可 被缓慢氧化为NO2。 NO2:红棕色有窒息性臭味的气体,能溶于水。 N20:稍带甜味和香气的无色惰性气体,单个分 子的温室效应为C02的200倍,并参与臭氧 层的破坏
NO：无色、无味、无臭，微溶于水，在大气中可 被缓慢氧化为NO2。 二、氮氧化物的性质 NO2 ：红棕色有窒息性臭味的气体，能溶于水。 N2O：稍带甜味和香气的无色惰性气体，单个分 子的温室效应为CO2的200倍，并参与臭氧 层的破坏
三、氮氧化物的危害 1)对人有致毒作用 2)对植物有损害作用 3)参与形成光化学烟雾,形成酸雨
三、氮氧化物的危害 1）对人有致毒作用 2）对植物有损害作用 3）参与形成光化学烟雾，形成酸雨