Investigation of flue-gas treatment with O3 injection using NO and NO2 planar laser-induced fluorescence

Simultaneous absorption of NOx and SO2 from flue gas with pyrolusite slurry combined with gas-phase oxidation of NO using ozone

“…Ozone has proved to be an efficient gas phase oxidant with advantages of selectivity, high oxidation efficiency, fast oxidation speed and nonpollution decomposition products, etc. [8,[17][18][19][20][21]. With respect to the liquid phase absorption of oxidized flue gas, NO x removal efficiency could reach more than 80% regardless of alkali liquor [8,18,19] or reducing Na 2 S [20,21] used.…”

“…The two independent systems can remove SO 2 and NO x step by step with high efficiency, but with drawbacks such as large areas, complex system, high investment and operation cost [7][8][9]. In order to overcome above-mentioned problems, a large number of strong oxidizing agents are added into NO x removal process [10][11][12][13][14][15][16][17][18][19][20][21] to obtain the satisfying NO x removal efficiency as SO 2 in wet process. These approaches are divided into absorption-oxidation process [2,[10][11][12][13][14] and oxidation-absorption process [8,[15][16][17][18][19][20][21].…”

“…In order to overcome above-mentioned problems, a large number of strong oxidizing agents are added into NO x removal process [10][11][12][13][14][15][16][17][18][19][20][21] to obtain the satisfying NO x removal efficiency as SO 2 in wet process. These approaches are divided into absorption-oxidation process [2,[10][11][12][13][14] and oxidation-absorption process [8,[15][16][17][18][19][20][21]. In absorption-oxidation process, liquid oxidants with strong oxidability are used as absorbent, such as sodium chlorite [10][11][12], hydrogen peroxide [13] and potassium permanganate [2,14].…”

“…Although using strong oxidizing agents can improve NO x removal efficiency, there are certain drawbacks, such as the expensive cost of oxidizing agents [4,22] and disposal problems of absorption solution [22]. While in oxidation-absorption process, gas phase oxidants, such as hydrogen peroxide [15,16] and ozone [8,[17][18][19][20][21], are injected into flue gas first to oxidize NO to NO 2 which is highly soluble in water, and then NO 2 and SO 2 can be removed simultaneously by wet removal process. Ozone has proved to be an efficient gas phase oxidant with advantages of selectivity, high oxidation efficiency, fast oxidation speed and nonpollution decomposition products, etc.…”

Fe3−Cu O4 as highly active heterogeneous Fenton-like catalysts toward elemental mercury removal

“…The Å OH radicals produced by Fenton-like reactions can oxidize and remove various pollutants with simple and secure process, low energy consumption, and no secondary pollution. During the past years, Fenton-like method has been widely applied for coal-fired flue gas cleaning Tan et al, 2007;Wang et al, 2010;Audenaert et al, 2011). Zhan et al (2013) developed a wet Ultraviolet (UV)/Fenton system to remove Hg 0 by setting a UV lamp into a lab-scale bubble reactor, and the oxidation process was enhanced by converting the insoluble Hg 0 into its soluble oxidized form and then removed by the wet scrubber.…”