活性分子O_3深度氧化结合湿法喷淋脱硝机理试验研究  

NOxremoval mechanism by O_3 oxidization integrated with wet scrubber

作　　者：马强[1] 朱燕群[1] 何勇[1] 张明慧[1] 林法伟 杨业[1] 王智化[1] 

机构地区：[1]浙江大学能源工程学院,杭州310027

出　　处：《环境科学学报》2016年第4期1428-1433,共6页Acta Scientiae Circumstantiae

基　　金：国家重点基础研究发展计划(No.2012CB214906);国家自然科学基金(No.51176169)~~

摘　　要：针对活性分子O_3氧化结合湿法喷淋脱硝技术,研究了O_3/NOx摩尔比和气相反应温度对NOx脱除效率的影响.试验结果表明,温度是决定臭氧脱硝效率的关键参数.在反应温度为90℃,O_3/NO摩尔比大于1.1的条件下,其脱硝效率要明显高于150℃的工况.这是因为在150℃反应温度条件下,臭氧与NOx反应遵循O_3+NO=NO2,基本不随O_3/NO摩尔比变化而改变;而90℃时,O_3/NOx<1.1,O_3+NO=NO2为主要反应,O_3/NOx>1.1时,臭氧会与NO2进一步发生深度反应,具体反应如下:NO2+O_3=NO_3+O2,NO2+NO_3=N2O5.由于N2O5在水中的溶解度要远高于NO2,故低温氧化结合湿法喷淋技术可实现NOx高效脱除.此外,通过傅里叶红外吸收光谱仪也检测到了N2O5的吸收峰.最后,用离子色谱仪分析了湿法喷淋后液相吸收产物中各阴离子的浓度,发现O_3/NOx=1.1工况下的吸收产物主要以NO-2为主,而O_3/NOx=2.1时则以NO-3为主,再一次验证了较低温度、O_3/NOx摩尔比较高时的氧化产物为N2O5的结论.Experimental investigation on the NOxremoval by ozone oxidization integrated with web scrubber was observed. Special focus was placed on the effects of O3/ NOxmolar ratio and the gas reaction temperature on NOxremoval efficiency. The results showed that oxidation temperature is critical for denitrification efficiency. When O3/ NOxmolar ratio is greater than 1. 1,the denitrification efficiency at reaction temperature 90 ℃ is higher than that of150 ℃. When the oxidation temperature is at 150 ℃,O3/ NOxreaction is followed by O3＋ NO = NO2,and basically does not change with O3/ NOxmolar ratio. At 90 ℃ and O3/ NOx〉 1. 1,O3＋ NO = NO2 is the dominant reaction,while as O3/ NOx〈 1. 1,ozone and NO2 would react to form NO3＋ O2 at the beginning,followed by NO2＋ NO3= N2O5. Since N2O5 is more soluble than NO2,integration with wet spray technology would achieve removal of NOxat low-temperature with higher efficiency. In addition,Fourier Transform Infrared Absorption Spectrometer（ FTIAR） also detected N2O5 existence.Finally the concentration of each anion in the liquid absorption after wet scrubber was analyzed by ion chromatography. When O3/ NOx= 1. 1,absorbing liquid product is mainly NO-2,and as O3/ NOx= 2. 1,the product is dominant as NO-3. This confirms that O3/ NOxmolar ratio is higher with lower oxidation temperature,and the main oxidation product is N2O5.

关 键 词：活性分子 脱硝 湿法喷淋 机理 N2O5 

分 类 号：X701[环境科学与工程—环境工程]