光催化联合海水NaHSO_(3)还原脱除船舶烟气中NO的研究

Study on removing NO from ship flue gas by photocatalysis combined with NaHSO_(3)/seawater reduction

为减少船舶柴油机烟气中NO的排放,将光催化技术与紫外/NaHSO_(3)高级还原技术联合还原脱除模拟烟气中NO。制备了Ag/TiO_(2-x)/泡沫陶瓷光催化剂,利用自制的光催化海水喷淋反应器考察了温度、液气比、NaHSO_(3)浓度、空速、NO浓度对脱硝率的影响。结果表明,随着温度的升高,脱硝率提高;液气比为3~6 L/m^(3)时,脱硝率变化较小;随着NaHSO_(3)浓度的增大,脱硝率先升后降;空速和NO浓度增大都不利于脱硝。光催化联合海水NaHSO_(3)能还原脱除NO,NO质量浓度为1000 mg/m^(3)时,脱硝率可达66.6%,N_(2)选择性为67.54%,NH_(4)^(+)选择性为13.16%。

In order to reduce NO emission in flue gas from marine diesel engine,a combination of photocatalytic technology and UV/NaHSO_(3) advanced reduction process is proposed to remove NO from the simulated flue gas.Ag/TiO_(2-x)/foam ceramic photocatalyst is prepared.The effects of temperature,liquid-gas ratio,NaHSO_(3) concentration,space velocity and NO concentration on denitration rate are investigated in a self-made photocatalytic seawater spray reactor with the photocatalyst.The results show that the denitration rate increases with the increase of temperature.The denitrification rate changes little when liquid-gas ratio is 3-6 L·m^(-3).With the increase of NaHSO_(3) concentration,the denitration rate increases firstly and decreases then.Higher space velocity and NO concentration are not conducive to denitration.Photocatalysis combined with NaHSO_(3) in seawater can reduce NO.The denitration rate can reach 66.6%,N_(2) selectivity is 67.54%,and NH_(4)^(+) selectivity is 13.16%when NO concentration is 1000 mg·m^(-3).