NOx Absorption Research Articles

Simultaneous Removal of SO2 and NO x Using Steel Slag Slurry Combined with Ozone Oxidation.

In this work, steel slag slurry was used in combination with O3 oxidation for the simultaneous removal of SO2 and NOx in a laboratory-scale wet flue gas desulfurization process. The effects of the oxidation temperature, steel slag concentration, initial SO2 concentration, and pH value on the desulfurization and denitrification efficiencies were studied. The results showed that the highest NOx removal efficiency occurred at an oxidation temperature of 90 °C. With an increase of the oxidation temperature above 90 °C, the denitrification efficiency decreased due to the decomposition of N2O5. The effect of the SO2 concentration on denitrification was complicated. When the concentration of SO2 was 500 ppm, generation of SO32– promoted the absorption of NO2. However, higher SO2 concentrations strengthened the competitive absorption of SO2 and NOx. In the pH range of 8.5–4.5, the denitrification efficiency was maintained at about 96%. The component analyses of the aqueous solution and the solid residue were conducted to investigate the compositions of the absorption products. The results showed that NO3– and SO42– were the major anions in the aqueous solution. The nitrogen balance was analyzed to be 95.8%, clearly illustrating the migration and transformation path of nitrogen. In the solid residue, most alkaline substances were consumed, and the final products were mainly CaSO4 and FeO. Accordingly, the reaction mechanism of simultaneous desulfurization and denitrification using steel slag combined with ozone oxidation was proposed.

A comparative study of the catalytic and non-catalytic ozone based processes for simultaneous of SO2 and NOX removal

Ozonation process alone is not sufficient to remove both the SO2 and NOX gases, when treated simultaneously. Therefore in this work, a suitable technique to remove SO2 and NOX simultaneously has been evaluated using combination of O3, H2O2 and a solid catalyst. OMS-2, a manganese based catalyst have been incorporated with O3 and H2O2 for enhanced radical generation. This preferably enhances the oxidation of SO2 and NOx species in aqueous medium simultaneously. The role of some important process parameters have been tested on the performance of SO2 and NOX absorption. To get the maximum removal of SO2 and NOX, the neutral pH, temperature close to 300–320 K, and H2O2 at 0.2 mol L−1 concentrations was found to be the optimum condition. The use of catalyst (approximately 2 g L−1) + O3 + H2O2 shows promising results on the removal of SO2 and NOX. In addition to that, the kinetics of the catalytic ozonation and peroxone removal of SO2 and NO2 has been evaluated. The cost estimation study for the ozone and peroxone based catalytic processes has been presented with comparison of the respective flue gas %removal.

Nox removal from gas mixture intensified by rotating packed bed with NaClO2 preoxidation

Stricter emission standards of NOx from marine exhaust call for efficient NOx removal method. In this work, a wet denitration intensification method conducted in novel Cross-flow rotating packed bed (CFRPB) reactor was proposed to meet the confined space requirement. In the CFRPB, the enhancement of oxidation and absorption were simultaneously achieved during NOx removal process. The NaClO2 and Na2SO3 solution were employed as liquid oxidant and absorbent, respectively. NOx oxidation was intensified by Gas-phase disturbance internal (GPDI) and multilayer wire mesh internals. The oxidation degree (α) was increased by 1.7 times after internal optimization. NOx absorption process was intensified via the high-gravity environment created by rotating packing. Effects of various operation parameters on NOx oxidation and absorption were also investigated. α and NOx removal efficiency (η) can reach up to 92% and 84%, respectively. Compared with traditional scrubbers, CFRPB has higher value of volumetric mass-transfer coefficient, which displays great potential for NOx removal from marine exhaust.

Study on removing NO from simulated marine diesel engine exhaust gas using the novel composite system of Ozone-Na2SO3/(NH2)2CO

The pollutants from the marine exhaust gas seriously threaten air quality and human health. Wet absorption is one of the most efficient NOx control pathways. The strict emission control regulations require the wet NOx control technology to have high NOx removal efficiency and the nitrate concentration of the absorption solution to be below 60 mg/L. The novel system of ozone-Na2SO3/(NH2)2CO could not only make the NOx absorption efficiency and the amount of nitrate residue fully meet the regulations but also effectively reduce the (NH2)2CO consumption and the nitrite concentration. The final product of NO was mainly N2 instead of nitrate. The effects of O3 concentration, Na2SO3 concentration, (NH2)2CO concentration, O2 concentration, SO2 concentration, initial pH value, and temperature were thoroughly investigated. The experimental results showed that the NOx removal efficiency was mostly influenced by the O3 concentration, Na2SO3 concentration, and the initial pH value. Moreover, the nitrate concentration was mainly controlled by Na2SO3 concentration and initial pH value. While the nitrite concentration was governed by the (NH2)2CO concentration and initial pH value. The increase of O3 concentration and Na2SO3 concentration promote NOx absorption. Although the decrease of initial pH value resulted in a slight increase of nitrate, it greatly reduced the content of nitrite. Furthermore, the increase of Na2SO3 concentration helped to improve the NOx removal efficiency and inhibited the generation of nitrate. Initial pH value was the critical parameter for the NO absorption process. Ozone-Na2SO3/(NH2)2CO composite system showed great application potential in the field of marine wet NOx control technology.

Simultaneous wet absorption of SO2 and NOX with mixed Na2SO3 and (NH4)2SO3: Effects of mass concentration ratio and pH

• Mixed Na 2 SO 3 and (NH 4 ) 2 SO 3 are employed as absorbents to remove NO X and SO 2 . • Effects of mass concentration ratio and pH are investigated. • High absorption efficiencies for SO 2 and NO X (over 93%) are obtained. • The initial pH of the absorbent affects the absorption performance. Wet flue gas desulfurization is considered as one of the most effective methods for the simultaneous removal of NO X and SO 2 in the flue gas. To investigate the absorption performance of NO X and SO 2 with the absorbents of Na 2 SO 3 and (NH 4 ) 2 SO 3 and study the controlling factors of the process, the sulfite-based mixed absorbents with different mass concentration ratios of Na 2 SO 3 to (NH 4 ) 2 SO 3 are employed for the gas removal in a bubble absorber. The results indicate that the absorbents have high absorption efficiency for SO 2 and NO 2 (all over 93%) with different mass ratios of Na 2 SO 3 to (NH 4 ) 2 SO 3 , and the absorbent with the proportion of 50%: 50% has the highest removal efficiency for NO (73.8%). The pH of the absorbent solution is a controlling factor affecting the absorption performance, and the alkaline condition is more conducive to absorption. The more the content of (NH 4 ) 2 SO 3 is, the lower the pH value and SO 2 absorption amounts are. Moreover, the absorbent with a ratio of 30%: 70% has the highest removal efficiency (99.6%) and also the highest absorption amount (2761 mg/100 g) of SO 2 (when the initial pH is the same). For the simultaneous absorption of NO X and SO 2 , the absorbent with a ratio of 30%: 70% has the highest removal efficiency (64.3% for NO X and 99.5% for SO 2 ).

Enhanced simultaneous absorption of NOx and SO2 in oxidation-reduction-absorption process with a compounded system based on Na2SO3

Oxidation of sulfite and competitive absorption existed in Na2SO3 solution for simultaneous removal of NOx and SO2, inhibited the long-term high-efficiency when used for practical applications. A matching strategy was developed to solve these problems. Antioxidants combination was used to retard the oxidation of antioxidant and enhance inhibition of S(IV) (tetravalent sulfur) oxidation. Hydroquinone (HQ) and sodium thiosulfate (ST) showed a positive synergistic effect on inhibition of S(IV) oxidation. When SO2 concentration was 500 and 2000 ppmV, the addition of 0.1 wt.% HQ and 1 wt.% ST decreased the percentage of S(IV) oxidized by oxygen by over 30% and 40%, respectively. Alkali (Na2CO3) alleviated the competitive absorption between NOx and SO2. Moreover, Na2CO3 exhibited an enhancement effect on the absorption of NOx and SO2 when coupled with anti-oxidants. While the increase of oxygen pressure accelerated the oxidation of S(IV), the anti-oxidants can retard the oxidation. The measurement of pH suggested the removal efficiency of NOx highly depended on SO32⁻ concentration rather than pH. The further investigation of the mechanism suggested the match effect was related to the interaction between ST and the intermediate product of HQ. The match strategy holds a potential for application of SO32⁻ to denitration.

Study on the role of copper converter slag in simultaneously removing SO2 and NOx using KMnO4/copper converter slag slurry

To achieve “waste controlled by waste”, a novel wet process using KMnO4/copper converter slag slurry for simultaneously removing SO2 and NOx from acid-making tail gas was proposed. Through the solid-liquid separation for copper slag slurry, the liquid-phase part has a critical influence on removing NOx and SO2. Also, the leached metal ions played a crucial role in the absorption of SO2 and NOx. Subsequently, the effects of single/multi-metal ions on NOx removal was investigated. The results showed that the leached metal from copper converter slag (Al3+, Cu2+, and Mg2+) and KMnO4 had a synergistic effect on NOx removal, thereby improving the NOx removal efficiency. Whereas Fe2+ had an inhibitory effect on the NOx removal owing to the reaction between Fe2+ and KMnO4, thereby consuming the KMnO4. Besides, SO2 was converted to SO42− completely partly due to the liquid catalytic oxidation by metal ions. The XRD and XPS results indicated that the Fe (II) species (Fe2SiO4, Fe3O4) in copper slag can react with H+ ions with the generation of Fe2+, and further consumed the KMnO4, thereby resulting in a decrease in the NOx removal. The characterization of the slags and solutions before and after reaction led us to propose the possible mechanisms. The role of copper slag is as follows: (1) the alkaline substances in copper slag can absorb SO2 and NO2 by KMnO4 oxidation. (2) copper slag may function as a catalyst to accelerate SO2 conversion and improve NOx removal by synergistic effect between leached metal ions and KMnO4.

Simultaneous Removal of NOx and SOx from Flue Gases Using ClO2: Process Scaling and Modeling Simulations

The concept of coabsorption of NO2 and SO2 from flue gases, in combination with the enhanced oxidation of NO by ClO2(g), is studied on three scales, 0.2, 100, and 400 N m3/h, all with flue gases of different origins. The results obtained from each setup are presented, together with modeling that was applied to assess the scale-up of the concept and to validate the model. The measurements confirm that ClO2 is highly selective toward NO oxidation for temperatures in the range of 70–155 °C. A comparison of the results obtained for each scale reveals that the 0.2 N m3/h setup confers a higher level of NOx absorption than the other setups, although the trends remain similar. Simulations of the results underpredict the level of NO2 absorption in the 0.2 N m3/h setup while capturing the levels of absorption in the 100 N m3/h setup. An important finding is the rapid and complete oxidation of S(IV) in the presence of NO2, which is not represented in the reaction kinetics.

A prospective absorption system for marine NOx removal from simulated gas using Na2SO3/urea composite absorbents in bubble reactor

The large amount of NOx emitted from ships causes great harm to the environment and to health. Due to the strict regulations on NOx emission, it is urgent to develop a marine NOx absorption technology with efficient NOx removal and less nitrate residue in scrubber water. This paper proposed a novel composite Na2SO3/(NH2)2CO absorption system that could efficiently absorb NOx from ships. The NOx absorption process was studied in combination with a bubble reactor. Na2SO3 could react with NOx to convert the N into nitrite and N2, and (NH2)2CO could reduce the nitrate, nitrite, and NOx to N2. The main key parameters such as Na2SO3 concentration, (NH2)2CO concentration, SO2 concentration, oxygen concentration, NOx oxidation degree, initial NOx concentration, initial pH, and temperature were investigated experimentally. The Na2SO3 concentration had great effects on the NOx absorption efficiency. The nitrate concentration was significantly affected by the absorbents concentration, the NOx oxidation degree, the temperature, and the O2 concentration (0%–8%). Acid condition was not conducive to NOx absorption. A NOx absorption efficiency of 92.3%, a nitrate content of 13.1 mg/L, and the nitrite content of 21.3 mg/L were achieved under the optimal conditions in which, Na2SO3 was 0.25 mol/L, (NH2)2CO was 0.4 mol/L, SO2 was 700 ppm, NOx oxidation degree was 20%, initial NOx was 1000 ppm, and O2 was 12%. The Na2SO3/(NH2)2CO absorption system satisfied the regulations on NOx removal efficiency and nitrate concentration of scrubber water and therefore showed excellent application prospects on ships.

Engineering practice and economic analysis of ozone oxidation wet denitrification technology

SO2 and NO emitted from coal-fired power plants have caused serious air pollution in China. In this study, a test system for NO oxidation using O3 is established. The basic characteristics of NO oxidation and products forms are studied. A separate test system for the combined removal of SO2 and NOx is also established, and the absorption characteristics of NOx are studied. The characteristics of NO oxidation and NOx absorption were verified in a 35 t·h−1 industrial boiler wet combined desulfurization and denitrification project. The operating economy of ozone oxidation wet denitrification technology is analyzed. The results show that O3 has a high rate and strong selectivity for NO oxidation. When O3 is insufficient, the primary oxidation product is NO2. When O3 is present in excess, NO2 continues to get oxidized to N2O5 or NO3. The removal efficiency of NO2 in alkaline absorption system is low (only about 15%). NOx removal efficiency can be improved by oxidizing NOx to N2O5 or NO3 by increasing ozone ratio. When the molar ratio of O3/NO is 1.77, the NOx removal efficiency reaches 90.3%, while the operating cost of removing NOx per kilogram is 6.06 USD (NO2).

Evaluation and sensitivity analysis of the ecosystem service functions of haze absorption by green space based on its quality in China

Evaluation of the ecosystem service functions of haze absorption by green space is important for controlling haze. In this study, the ecosystem service functions of haze absorption by green space in China in 2001, 2004, 2007, 2010, 2013, 2016 and 2018 are analyzed based on green space quality and sensitivity using a geographic information system (GIS) and Moderate Resolution Imaging Spectroradiometer (MODIS) imagery. The results showed that the benchmark ecosystem service functions of haze absorption by green space when considering only the area of green space showed a trend that increases first and then decreases in 2001–2018, with 9000458.55 million Kg, 9145110.75 million Kg and 7734526.75 million Kg in 2001, 2013 and 2018, respectively. However, the corrected functions based on green space quality were 7724215.34 million Kg, 8320301.79 million Kg and 6510132.55 million Kg in the corresponding years. This indicated large differences between ecosystem service functions of haze absorption based on the quality and area of green space; only considering the area of green space to evaluate ecosystem service functions will result in overestimation. In terms of the spatial distribution of the ecosystem service functions of haze absorption by green space, there were greater differences in the benchmark and corrected functions, and the spatial distributions of the maximum, intermediate and minimum ecosystem service functions were notably different. However, the benchmark and corrected functions all showed a consistent trend in the rank of their contribution rates and ecosystem service functions as well as consistent distribution trends: the spatial distribution of ecosystem service functions of haze absorption by green space was very different in the same year, but there was little difference among different years. The change coefficients for the ecosystem service functions of haze absorption by arable land and grass land remained stable, whereas the coefficient of sensitivity for forest cover was elastic. Patch density (PD) and the ecosystem service functions of SO2 absorption, NOx absorption, dust retention and total ecosystem services showed a significant negative correlation, with correlation coefficients of -0.407, -0.511, -.330 and -0.332, respectively. In contrast, the area-weighted mean shape index (SAPE_AM) and ecosystem service functions exhibited significant positive relationships with correlation coefficients of 0.650, 0.634, 0.568 and 0.570, respectively. The results provide an improved method for evaluating the ecosystem service functions of haze absorption by green space as well as a reference for the prevention and control of haze and the coordinated development of regional societies, the economy and the environment.

Optimization of SO2 and NOx sequential wet absorption in a two-stage bioscrubber for elemental sulphur valorisation.

Flue gases contain SO2 and NOx that can be treated together for elemental sulphur recovery in bioscrubbers, a technology that couples physical-chemical and biological processes for gaseous emissions treatment in a more economic manner than classical absorption. Sequential wet absorption of SO2 and NOx from flue gas is thoroughly studied in this work in a two-stage bioscrubber towards elemental sulphur valorisation pursuing reuse of biological process effluents as absorbents. The optimal operating conditions required for SO2 and NOx absorption in two consecutive spray absorbers were defined using NaOH-based absorbents. Overall, removal efficiencies of 98.9% and 55.9% for SO2 and NOx abatement were obtained in two in-series scrubbers operated under a gas contact time of 1 and 100 s, and a liquid-to-gas ratio of 7.5 and 15 L m-3, respectively. Higher NOx removal efficiency to clean gas emission was obtained by oxidants dosing in the absorber for NOx absorption. High NaHCO3 concentration in a two-stage bioscrubber effluent was exploited as alkaline absorbent for flue gas treatment. The performance of scrubbers using an absorbent mimicking a reused effluent exhibited the same removal efficiencies than those observed using NaOH solutions. In addition, the reuse of bioprocess effluent reduced reagents' consumption by a 63.7%. Thus, the two-stage bioscrubber proposed herein offers an environmentally friendly and economic alternative for flue gas treatment.

Characteristics of HCl Release and SO2/NOx Absorption in Desulfurization Wastewater Evaporation Using Hot Flue Gas

Desulfurization wastewater (DW) can be effectively treated via evaporation using hot flue gas with zero DW discharge. In this study, the characteristics of HCl release and SO2/NO2 absorption were i...

Pretreated water-quenched-manganese-slag slurry for high-efficiency one-step desulfurization and denitrification

Presently, researches on the use of low-cost pulp or slag for desulfurization and denitrification has attracted much attention globally. However, the efficiency of the NOx conversion remains low and has a short duration. Therefore, we tried to activate the water-quenched-manganese-slag (WQMS) through the pretreatment method of calcination and additive calcination then mixed with KMnO4 (oxidation and absorption in one step without pre-oxidation). The obtained removal efficiency of NOx and SO2 was high as 84.9% and 100% under optimal conditions. After adding the pre-treated WQMS, the absorption of NOx by the slurry increased to 228.65 mg/L when denitrification rate was more than 65%, which is 3.6 times that of pure KMnO4. The increased denitrification efficiency after pre-processing was affected by the phase structure change of the WQMS, increased valence state of manganese, as well as the higher alkalinity of the WQMS. Furthermore, the mechanism of simultaneous desulfurization and denitrification was proposed. In summary, this study provided a new one-step strategy to simultaneously remove SO2 and NOx.

Simultaneous desulfurization and denitrification of flue gas by pre-ozonation combined with ammonia absorption

Abstract A process of simultaneous desulfurization and denitrification of flue gas was conducted in this study. The flue gas containing 200 mg·m−3 NO, 1000–4000 mg·m−3 SO2, 3%–9% O2, and 10%–20% CO2 was first oxidized by O3 and then absorbed by ammonia in a bubbling reactor. Increasing the ammonia concentration or the SO2 content in flue gas can promote the absorption of NOX and extend the effective absorption time. On the contrary, both increasing the absorbent temperature or the O2 content shorten the effective absorption time of NOX. The change of solution pH had substantial influence on NOX absorption. In the presence of CO2, the NOX removal efficiency reached 89.2% when the absorbent temperature was raised to 60 °C, and the effective absorption time can be maintained for 8 h, which attribute to the buffering effect in the absorbent. Besides, both the addition of Na2S2O3 and urea can promote the NOX removal efficiency when the absorbent temperature is 25 °C, and the addition of Na2S2O3 had achieved better results. The advantage of adding Na2S2O3 became less evident at higher absorbent temperature and coexistence of CO2. In all experiments, SO2 removal efficiency was always above 99%, and it was basically not affected by the above factors.

Simultaneous removal of SO2 and NO using a novel method with red mud as absorbent combined with O3 oxidation

Aiming at SO2 and NOx in industrial flue gas, the simultaneous removal of SO2 and NOx was conducted using red mud as absorbent with O3 oxidation. The effects of different factors on the desulfurization and denitration efficiency were investigated. The results show that the increase of oxidation temperature is not conducive to the absorption of NOx (O3/NO molar ratio >1). Low concentration of SO2 promotes the absorption of NOx, however high concentration of SO2 inhibits absorption of NOx. The main product after desulfurization and denitration of red mud solid residue is bassanite (CaSO4·0.5H2O). In addition, when the pH is greater than 5, calcium carbonate and sodium alkali play major roles in red mud, and when 3.5< pH < 5, sodium aluminosilicate hydrate (1.08Na2O·Al2O3·1.68SiO2·1.8H2O), calcium nepheline (Na6CaAl6Si6(CO3)O24·2H2O) and garnet (Ca3Al2(SiO4)(OH)8) take part in the reaction. According to typically practical conditions with oxidation temperature at 130 °C and the O3/NO molar ratio being 1.8, the desulfurization efficiency of red mud can reach 93 % in the first hour, and the denitration efficiency can be maintained at about 87 %. Besides, the reaction mechanism with multi oxidation absorption steps was also proposed.

Computer simulation of NOx removal from diesel engine off-gases under electron beam and wet scrubber system

NOx emission from diesel engine off-gases in marine transportation sector is still an environmental issue to be solved in present day. Electron beam (EB) followed by a seawater wet scrubber method to removal NOx has been experimentally studied (Chmielewski et al., 2018). In this work numerical simulation of NOx reduction using EB followed by a water scrubber system has been carried out. The first stage was to calculate NOx removal versus dose under EB irradiation. Computer code “KINETIC” and Gear method were used, the model has been improved based our previous work (Zwolinska E. et al., 2015) and verified by the experimental results. The calculation results of NOx removal efficiency was 4.9% at 10.9 kGy dose under EB irradiation, which was a little higher than experimental value (3.5%). Computer program MATLAB was used to study NOx absorption in water. The NOx removal efficiency was increased by 17.5% at 10.9 kGy dose for inlet concentration of NOx being 1333 ppm after EB-water absorption process. At the end, NOx reduction in the simulated marine off-gas using microwave plasma was simulated using computer program Chemical Workbench. Less than 20% NOx was removed from the off-gases in microwave plasma reactor even at 9000 kGy dose for the inlet concentration of NOx being 1500 ppm. EB is more energy efficient than microwave plasma for NOx removal.

Recyclable MFe2O4 (M = Mn, Zn, Cu, Ni, Co) coupled micro-nano bubbles for simultaneous catalytic oxidation to remove NO x and SO2 in flue gas.

NOx can be efficiently removed by micro–nano bubbles coupling with Fe3+ and Mn2+, but the catalyst cannot be reused and the adsorption wastewater should be treated. This work developed a new technology that uses micro–nano bubbles and recyclable MFe2O4 to simultaneously remove NOx and SO2 from flue gas, and clarified the effectiveness and reaction mechanism. MFe2O4 (M = Mn, Zn, Cu, Ni and Co) prepared by a hydrothermal method was characterized. The results show that MFe2O4 can be activated to produce ˙OH which can accelerate the oxidation absorption of NOx. Compared with no catalyst, the NOx conversion rate increased from 32.85% to 83.88% in the NOx–SO2–MFe2O4-micro–nano bubble system, while the removal rate of SO2 can reach 100% at room temperature. The catalytic activities of MFe2O4 showed the following trend: CuFe2O4 > ZnFe2O4 > MnFe2O4 > CoFe2O4 > NiFe2O4. The results provide a new idea for the application of advanced oxidation processes in flue gas treatment.

Oxidation of NO with O3 under different conditions and the effects of SO2 and H2O vapor

In order to achieve better chemical absorption of NOx and SOX, oxidation of NO in the process of simultaneous desulfurization and denitrification of the flue gas based on ozone oxidation was studied. The main investigations focused on factors affecting NO oxidation including the molar ratio of O3/NO (MR) (0.6–1.2), the oxidation temperature (65−150°C), the initial NO concentration (100−500mg/Nm3), the presence of SO2 (1000−5000mg/Nm3), the content of water vapor (5–15 %) and the residence time (0.07–1.8s). The results indicated that MR had a substantial effect on NO conversion and the products of NO oxidation by O3 varied with the change of MR. When MR≤1, the NO conversion increased from less than 60 % to more than 95 % with the increase of MR, and the oxidation product was mainly NO2. When MR(O3/NO) > 1, the NO conversion rate (about 97 %) basically remained unchanged, and the oxidation products under these circumstances were mainly NO2 and N2O5. When the oxidation temperature rose from 65 to 150℃, the conversion of NO was almost unchanged. Besides, the NO initial concentration, the presence of SO2, the water vapor content and the length of the flue gas outlet pipe had negligible impact on the NO conversion within the range selected for the study.

Technical-Scale Evaluation of Scrubber-Based, Co-Removal of NOx and SOx Species from Flue Gases via Gas-Phase Oxidation

The co-absorption of SOx and NOx supported by the enhanced oxidation of NO by ClO2(g) from flue gases is investigated through technical-scale experiments and simulations. In focus is NOx absorption and the oxidation of S(IV) to S(VI). The concept was tested using the flue gases from a 100-kW gas-fired furnace, to confirm findings previously obtained at the technical scale. The chemical interactions that occurred between NOx, SOx and the ClO2, used as an oxidizing agent were investigated. The measurements confirm that the absorption of SO2 in the scrubber is efficient and mainly determined by saturation in the scrubber liquid. The absorption of NO2 peaked at 82% when Na2SO3 and Na2CO3 were added to the scrubber liquid. The results indicate that the efficiencies of removal of NOx and SOx can be high (>90% and >99%, respectively). This work provides a first proof-of-concept on a technical scale and validates the reaction mechanism proposed in previous studies.