Journal articles: 'Denitration efficiency'

1

Zhang, Wei, and Zhenglin Yu. "Study on flue gas denitration method based on multistage high gravity technology." E3S Web of Conferences 385 (2023): 01011. http://dx.doi.org/10.1051/e3sconf/202338501011.

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According to the mechanism of wet denitration, H2O2 solution and KOH solution are used as absorbents, and the two-stage countercurrent high-gravity rotating packed bed is used as the reaction equipment. The rotating speed, gas-liquid ratio, temperature, H2O2 solution concentration and KOH solution concentration are changed respectively to explore the impact of various factors on the denitration efficiency, and finally determine the best experimental conditions for flue gas denitration. The experimental results show that when the rotating speed reaches 900 rpm, the gas-liquid ratio is 12:1, and the temperature reaches 36 °C, using 0.20 mol/l of H2O2 solution and 0.10 mol/l of KOH solution as absorbents, the denitration efficiency can reach the best, and the best denitration efficiency is 95.71%.

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Huang, Dewei, Xiaochun Yin, and Huaiping Ding. "Numerical simulation of the denitrification process in the sintering flue gas SCR reactor and optimization of the ammonia injection process." E3S Web of Conferences 625 (2025): 02016. https://doi.org/10.1051/e3sconf/202562502016.

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Iron ore sintering is an important process in ironmaking. To reduce the emissions of harmful gases such as nitrogen oxides during the sintering process, the SCR(Selective Catalytic Reduction) denitration technology can be adopted to remove nitrogen oxides and others. Based on the problem of low denitration efficiency of the SCR reactor in a certain steel plant, the Fluent software was used to numerically simulate the flow field and the denitration reaction process of the SCR reactor, and to analyze the reasons for the low denitration efficiency of the SCR reactor. According to the results of numerical analysis, the ammonia injection process was optimized. Through the finite element modeling of the optimized design scheme, the mixing degree of ammonia and nitrogen oxides and the denitration efficiency were re-analyzed. The analysis results show that the optimized design scheme effectively improves the uniformity of the ammonia-nitrogen concentration ratio above the first layer of catalysts. The original denitration efficiency of 55% is increased to 83%, which meets the requirements of the emission standards.

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Hu, Man Yin, Yi Jing Jin, Xiu Hong Wang, and Yu Sun. "Study of SCR Denitration Efficiency under Different Boiler Load Conditions." Advanced Materials Research 219-220 (March 2011): 600–603. http://dx.doi.org/10.4028/www.scientific.net/amr.219-220.600.

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With the use of energy, the pollution is more and more serious. As the largest pollution family, coal-fired power plant must control the pollution strictly. It established model of a coal-fired power plant SCR system, and simulated the denitration under different boiler load conditions, to get the denitration efficiencies and the regular of the denitration efficiency under different boiler load conditions. It can provide recommendations for practicality run in coal-fired power plant SCR system.

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Wang, Ya Li, Li Nan, Si Yu Peng, Yun Ning Zhang, Mei Na Chen, and Su Ping Cui. "Effect of Cement Raw Material and Oxygen Concentration on SNCR Reaction." Materials Science Forum 913 (February 2018): 969–75. http://dx.doi.org/10.4028/www.scientific.net/msf.913.969.

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As the selective non-catalytic reduction denitration(SNCR denitration) was used in cement decomposition furnaces under the high concentration cement raw materials and complex flue gas composition , the denitration efficiency is poor and the reducing agent is largely consumed.In order to meet the more stricter requirements of environmental protection, there is an urgent need to improve the denitration efficiency of SNCR and reduce the escape of reducing agentsin order to prevent the unnecessary waste caused by excessive use of reducing agents and secondary atmospheric pollution.Therefore, studying the effect of cement raw materials and O2 concentration on SNCR process is very important. In this paper, the initial concentration of NO and the ammonium to nitrogen ration (CNH3/CNO) was 800ppm and 1.5, respectively. The effects of cement raw material and oxygen concentration on the reaction process of NH3+NO+O2 in the temperature range of 750°C -1100°C were investigated by means of denitration rate, in Situ DRIFTS analysis.The results demonstrate when O2 concentration was 5% and denitration temperature was 950°C, the deNOx rate reached a maximum of 89.64%, which due to O2 promoted NH3 and NO to react with O2 to produce N2 and H2O. However,under the effect of cement raw material, O2 can promote NH3 which was adsorbed on the surface of cement raw material to react with O2 and produce NO and H2O, and the reaction of oxidation of NH3 is dominant, therefore, the denitration reaction is inhibited. .When O2 concentration was 5% and temperature was 850°C, the deNOx rate reached a minimum value of -109.09%. the high concentration cement raw material and flue gas composition reduce the denitration efficiency of cement kiln.

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5

Zheng, Tao, Ying Tao, Xudong Luo, et al. "Application of an integrated device for ultra-low temperature desulfurization and denitration in large rotary kiln." Transactions on Engineering and Technology Research 2 (August 6, 2024): 15–18. http://dx.doi.org/10.62051/fpfbjm39.

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To tackle the problem of excessive nitrogen oxide emissions during the denitration process of the lime rotary kiln at Beitai Iron Mine, it was proposed to integrate ultra-low temperature SCR denitration catalysts and a moving-burden bed reactor into a radial combined desulfurization and denitration device to achieve ultra-low temperature denitration in a low-sulfur state. The self-built integrated device features two desulphurization beds and one denitration bed, through which the flue gas passes successively in a radial flow manner. Industrial test results indicate that the denitration efficiency reached an average of 96.07% at temperatures ranging from 70 to 130°C during a 14-day test period, indicating a good denitration effect. The ultra-low temperature SCR denitration device has been put into use, effectively reducing nitrogen oxide emissions and air pollution, while also promoting the optimization and upgrading of the energy structure. The research results can provide a reference for the environmental management of mining and processing enterprises.

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Sun, Wanying, Mengmeng Ye, Yihua Gao, et al. "Effect of Catalyst Inlet Flow Field Distribution Characteristics on Outlet NO Concentration Distribution in SCR Denitration Reactor Based on Monte Carlo Method." Atmosphere 13, no. 6 (2022): 931. http://dx.doi.org/10.3390/atmos13060931.

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Selective catalytic reduction (SCR) technology plays a crucial role in flue gas denitration. The nonuniform distribution of catalyst inlet parameters causes the nonuniform distribution of NO concentration at the outlet, thus affecting accuracy of ammonia injection. Regarding this issue, this paper describes the impacts of nonuniform velocity and temperature on both the confidence of NO concentration measured at a single measuring point at the outlet and the denitration efficiency, which can provide a basis for structural optimization of SCR denitration reactor and decrease in ammonia slip. The random distribution form of velocity and temperature above the catalyst layer are derived from the actual gas volume and the actual SCR reactor model, and then the catalyst inlet boundary conditions were generated with different relative standard deviation of velocity and temperature accordingly. The confidence of outlet NO concentration measurement results can be counted by means of Monte Carlo simulation. Finally, the relation model can be obtained to calculate the confidence of outlet NO concentration measurement results at different working conditions. The results show that within the gas volume range of this work, in order to ensure the confidence of the NO concentration measurement results, the relative standard deviation of temperature before the catalyst inlet must be within 0.005 and the relative standard deviation of velocity before the catalyst inlet must be within 0.1. With the increase in relative standard difference in temperature, there is a slight decrease in the efficiency of denitration. With the different mean value of temperature, the variation range of denitration efficiency is similar to that of temperature-relative standard difference. With the different mean value of velocity, the deviation range of corresponding efficiency is similar to that of the temperature-relative standard difference. When the relative standard difference in velocity increases, the denitration efficiency decreases slightly. The greater velocity value, the decreasing range of denitration efficiency is larger than the variation range of relative standard difference in velocity.

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7

Zhang, Li Juan. "The Design and Experimental Study on the Lance of the Cement Industry Flue Gas Denitration Technology." Advanced Materials Research 1015 (August 2014): 663–66. http://dx.doi.org/10.4028/www.scientific.net/amr.1015.663.

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The lance is the key equipment of SNCR flue gas denitrification technology injection system on the new dry process cement production line.The atomizing effects of reducing agent will directly influence the result of flue gas denitration. In this paper, there are the structure design and experimental analysis on denitration lance.The results show that the lance can ensure the average diameter of atomized particles is from 50 to 55um,uniformly degree is above 80%, and visual distance of atomized ammonia is above 4 meters.It has been applied in a new dry process cement production line of daily 5kt SNCR flue gas denitration project, reaching above 70% of denitration efficiency. These results are valuable for similar new dry cement clinker production line of SNCR denitration Technology.

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8

Yang, Yingxin, Lu Zhong, Jingling Hu, Xueliang Xue, Xiaotu Hu, and Yong Liu. "Investigation on NO Oxidation during Ozone Oxidation Denitration of Sintering Flue Gas." E3S Web of Conferences 53 (2018): 01027. http://dx.doi.org/10.1051/e3sconf/20185301027.

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With the intensified requirements on ambient air quality, controlling NOx emission from sintering flue gas has become the most important priority in steel industry. Ozone oxidation denitration process has become the most closely watched sintering flue gas denitration technology. In order to investigate the influence of different operating conditions on NO oxidation in practical engineering application of ozone oxidation denitration process, an ozone oxidation system was built, and sintering flue gas was extracted from the pipeline between the induced draft fan and the desulfurization tower. The influence of discharge power and O2 flow rate of ozone generator on O3 concentration, O3 yield and NO oxidation efficiency were investigated. The results indicated that NO oxidation efficiency increased with the discharge power. And the increase of O3 dosage imposed a significant influence on NO oxidation efficiency. However, little effect of O2 flow rate on NO oxidation efficiency was observed.

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Wenfeng, Hao*. "EXPERMENTAL STUDY ON SEQUENCE HEATING REACTION BETWEEN NITRIC OXIDE AMMONIA." INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY 6, no. 4 (2017): 144–48. https://doi.org/10.5281/zenodo.496109.

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A tubular reactor with a sequence heating device is used to discuss the effects of operational parameters for the reaction between nitric oxide and ammonia. Experimental results showed that denitration efficiencies had been developed to become a parabola with the change of reaction time under a certain NH3/NO mole ratio and under a certain temperature and that denitration efficiencies also had changed to become a parabola with the increase of the reaction temperature when a NH3/NO mole ratio was identified. Denitration efficiencies of 91.6 percent could be reached when the optimal NH3/NO mole ratio, optimal reaction temperature, and reaction time respectively were 1.2, 320 ℃ and 14min in this work.

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10

Xu, Xi. "Experimental research on performance test after SCR denitration system ultra-low emission retrofit in a 600 MW coal-fired unit." E3S Web of Conferences 136 (2019): 02034. http://dx.doi.org/10.1051/e3sconf/201913602034.

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A systematic performance test was carried out for the ultra-low emission modification project of the Selective Catalytic Reduction (SCR) denitration system of a 600 MW coal-fired unit in a thermal power plant. Terms of the performance tests include denitration efficiency, ammonia escape rate, and SO2/SO3 conversion rate. The distribution of gas velocity and NOx concentration in flue gas of SCR inlet and outlet were summarized. The effect of unit load and gas velocity to denitration efficiency, ammonia escape rate and SO2/SO3 conversion rate were discussed after the test. The result favours design and retrofit of the ultra-low emissions coal-fired power unit in China. Through technical trials, a set of practical test methods suitable for the actual situation was concluded.

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11

Yang, Liang, Yunkai Cai, and Lin Lu. "Experimental Study on Simultaneous Desulfurization and Denitrification by DBD Combined with Wet Scrubbing." Applied Sciences 11, no. 18 (2021): 8592. http://dx.doi.org/10.3390/app11188592.

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A dielectric barrier discharge (DBD) reactor combined with a wet scrubbing tower was used to carry out an experimental study on desulfurization and denitrification. The effects of the packing type, packing height, spray density, mass fraction of the NaOH solution, discharge power in the DBD reactor, and simulated flue gas flow rate on the desulfurization and denitrification efficiency were analyzed, along with the influence weight of each factor, using orthogonal testing. The experimental results showed that SO2 was easily absorbed by the scrubbing solution, while the desulfurization efficiency remained at a high level (97–100%) during the experiment. The denitration efficiency was between 12 and 96% under various operating conditions. Denitration is the key problem in this system. The influence weights of the DBD power, simulated flue gas flow rate, mass fraction of the NaOH solution, spray density, packing type, and packing height on the denitration efficiency were 56.96%, 18.02%, 11.52%, 5.02%, 4.33%, and 4.16%, respectively. This paper can provide guidance to optimize the desulfurization and denitrification efficiency of this DBD reactor combined with a wet scrubbing system.

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12

Liu, Chongfei, Xuetao Wang, Lili Xing, et al. "Effect of Zr Modification on NH3-SCR Reaction Performance of Cu-Ce/SAPO-34 Catalysts." Applied Sciences 13, no. 8 (2023): 4763. http://dx.doi.org/10.3390/app13084763.

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Molecular sieve catalysts containing transition metals have been attracting attention for their potential applications in various fields, including environmental and industrial catalysis. A Cu-Ce-Zr/SAPO-34 series of molecular sieve catalysts were prepared by the impregnation method, and the effect of Zr introduction on the selective catalytic reduction of NO by Cu-Ce/SAPO-34 molecular sieve catalysts was explored. Through various characterization methods, the physical and chemical properties of the catalysts were analyzed, and the denitration mechanism of the molecular sieve catalyst was discussed. This study found that the total acid content of the acid sites on the catalyst surface decreased with the introduction of Zr, leading to a decrease in the denitration efficiency of the catalyst. At 350–400 °C, the denitration efficiency of the 4Cu-4Ce-4Zr/SAPO-34 catalyst was over 80%, and at 400–500 °C, it was over 99%. Moreover, excessive metal Zr could destroy its CHA structure and decrease the denitration efficiency of the catalyst. This study analyzed the reaction mechanism of NH3-SCR of Zr-modified polymetallic zeolites and the effect of Zr modification on the NH3-SCR reaction results. This study contributes to the understanding of the performance of molecular sieve catalysts containing transition metals. Reliable conclusions were obtained, which offer data support for future research in the field of NH3-SCR.

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13

Qie, Junmao, Tong Xu, and Zefeng Zhao. "Study on the Denitration Performance of Sulfuric Acid-Modified Columnar Catalysts Derived from Rare Earth Tailings." E3S Web of Conferences 628 (2025): 01001. https://doi.org/10.1051/e3sconf/202562801001.

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Currently, the massive accumulation of Bayan Obo rare earth tailings in Baotou City, Inner Mongolia, has imposed significant pressure on the local ecological environment. The Fe and Ce elements contained in these tailings possess potential as active components for denitration catalysts. However, their inherent denitration efficiency remains relatively low, necessitating integration with other treatment processes for performance enhancement. This study employed sulfuric acid activation modification combined with extrusion molding technology to prepare columnar rare earth tailing catalysts using Bayan Obo rare earth tailings as raw materials, aiming to develop cost-effective NH3-SCR denitration catalysts with high catalytic activity. The results demonstrated that sulfuric acid-modified rare earth tailings exhibited substantially improved denitration efficiency compared to raw materials, achieving a maximum efficiency of 87.4% at 400°C. The introduction of SO42- increased surface acidic sites on the catalyst, thereby enhancing NH3 adsorption capacity and strengthening the Eley-Rideal (E-R) mechanism, which collectively contributed to the improved catalytic performance. Furthermore, the formation of various sulfates (e.g., CaSO4 and MgSO4) during sulfuric acid modification significantly enhanced the mechanical strength of the catalysts. This approach not only achieves high-value utilization of mining waste through modified activation but also aligns with the green environmental concept of "using waste to control pollution." The findings provide significant insights for promoting resource-efficient societal development and sustainable environmental management.

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14

Liu, Ran, Yanting Liu, Yanjia Gao, and Qian Hu. "Study on Denitration Performance of Mn-Ce/TiO2 Low-Temperature SCR Catalyst." Metals 13, no. 2 (2023): 426. http://dx.doi.org/10.3390/met13020426.

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Low sintering flue gas temperatures and large temperature fluctuations require the development of low-temperature and efficient SCR (selective catalytic reduction) catalysts suitable for the sintering process. It has been shown that modified Mn-Ce/TiO2 catalysts have good denitration capability and have potential commercial use. In this experiment, TiO2-loaded Mn and Ce SCR catalysts were prepared using the impregnation method, and a series of characterizations of the samples were carried out to illustrate the effect of the active material on the denitration efficiency. The kinetic analysis provides theoretical as well as data support for the subsequent optimization of the SCR catalysts. The results show that the denitration efficiency of the catalysts can reach 93.86% when the Mn content is 10% and the Ce content is 3%. The doping of active substances can increase the specific surface area, total pore volume and average aperture of the catalysts and improve the adsorption capacity of the catalysts.

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15

Yang, Yingxin, Lu Zhong, Xueliang Xue, Jingling Hu, Xiaotu Hu, and Yong Liu. "Orthogonal Experiments on Ozone Oxidation Denitration of Sintering Flue Gas." E3S Web of Conferences 53 (2018): 01028. http://dx.doi.org/10.1051/e3sconf/20185301028.

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Ozone oxidation denitration process has become the most closely watched sintering flue gas denitration technology currently. In order to investigate the influence of different operating conditions on NO oxidation in practical engineering application of this technology, an ozone oxidation system was built, and sintering flue gas was extracted from the pipeline between the induced draft fan and the desulfurization tower. The influence of flue gas flow and inlet NO concentration on NO oxidation was investigated by orthogonal experiments. The results indicated that NO oxidation efficiency increased with the O3 yield of ozone generator and O3 dosage under any flue gas conditions. Under the same inlet NO concentration, NO oxidation efficiency decreased with the increase of flue gas flow. Under the same flue gas flow and O3 dosage, with the increase of inlet NO concentration, the O3 utilization rate increased while the average oxidation energy consumption of each NO molecule decreased, which was beneficial to promote the NO oxidation efficiency. In practical engineering application, the setting of O3 dosage should take into account both engineering design indicators and economy. Ozone oxidation denitration process could achieve NO oxidation efficiency higher than 90% through reasonable design, indicating a good industrial application prospect in the treatment of sintering flue gas.

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Shi, Deqi, Guoxin Sun, and Yu Cui. "Study on the removal of NO from flue gas by wet scrubbing using NaClO3." Journal of the Serbian Chemical Society 84, no. 10 (2019): 1183–92. http://dx.doi.org/10.2298/jsc190305053s.

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In order to remove nitric oxide (NO) from flue gas, from small coal-fired boilers, it is necessary to exploit the cost-effective wet denitration technology. The absorption of NO with sodium chlorate solution was studied. The effects of experimental conditions, such as temperature, NaClO3 concentration, type of acid, mole ratio of NaClO3 to hydrogen ions, on NO removal rate were investigated, and the optimal conditions were established. As the effect of temperature on denitration was related to the type of acid used, the temperature required for sulfuric acid was high, and the temperature required for nitric acid was low. The optimal mole ratio between NaClO3 and the two types of acids was the same. The reaction products were analyzed by ion chromatography. The reacted solution could be recycled after the removal of sodium chloride. The reaction mechanism and the total chemical reaction equation of NaClO3 denitration were deduced. The thermodynamic derivations showed that this oxidation reaction could proceed spontaneously and the reaction was very thorough. NaClO3 exhibited high NO removal efficiency and its denitration cost was much lower than sodium chlorite.

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17

Wang, Zhuang Kun. "Research of Microwave - Ethanol Auxiliary V₂O₅-WO₃/TiO₂ SCR Catalyst Regeneration Experiment." Advanced Materials Research 1015 (August 2014): 619–22. http://dx.doi.org/10.4028/www.scientific.net/amr.1015.619.

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Using selective catalytic reduction (SCR) that takes NH3 as the reducing agent to remove NOx is one of the most often used coal-fired flue gas denitration technology that of the highest denitration efficiency. As the core of the SCR system, catalyst is the important factors that affect the whole SCR system denitration efficiency. As the growth of the running time, catalyst tends to lose active energy because of the surface channel jam and toxic element enrichment and deactivation. Each year the deactivation catalyst regeneration process, can save a lot of money, thus help to avoid pollution of the environment. So study of the SCR catalyst regeneration technology is around the corner, which is of great practical significance for lowering the cost of the SCR system, promoting the application of the SCR technology, and protecting the environment. In this paper, the research takes vanadium series SCR catalysts as the object to study the regeneration technology of catalyst, new physical structure recovery method, and effect of regeneration process in the treatment on the performance of catalyst.

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18

Liu, Hai Long, Yan Liu, Jin Gang Wang, and Shao Feng Zhang. "Experiment Research on Calcium Hypochlorite for Flue Gas Desulfurization and Denitration." Advanced Materials Research 518-523 (May 2012): 2509–13. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.2509.

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In this paper the desulfurization and denitration of simulation flue gas using calcium hypochlorite as absorbent was studied experimentally. Absorption experiments of the desulfurization and denitration in calcium hypochlorite solutions were carried out in a Porous Globular Gas Liquid Reactor (PGGLR) which was a new and innovative core design. Three experiments were conducted at NTP conditions. The mechanism of removal for SO2 and NOX was investigated. Under these experiment conditions, the removal efficiency of 100%, 67% for SO2 and NOX were achieved. The results can offer valuable references for industrial application.

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Zhang, Yun Ning, Ya Li Wang, Su Ping Cui, Wei Wang, and Yi Ning Zhao. "Effect of CaO on SNCR Reaction with NH₃ as Reducing Agent." Materials Science Forum 847 (March 2016): 249–55. http://dx.doi.org/10.4028/www.scientific.net/msf.847.249.

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Selective non-catalytic reduction (SNCR) is a denitration method in the high temperature area, and NH3 or urea is used for SNCR as reducing agents to react with NOX to produce N2 in the flue gas in the temperature ranged from 850°C to 1100°C. The SNCR deNOx technology has been well used in utility boiler, but compared with it, the lower denitration efficiency and the larger consumption of ammonia indicate a more complex process in cement pre-calciner. Unlike in utility boiler, the presence of high concentrations of cement raw materials may influence SNCR denitration reaction process in cement kilns. Therefore, studying the effect of CaO which occupy the major composition of cement raw material is very important in SNCR process. In this study the influence of CaO on the SNCR deNOx process was investigated by simulating SNCR reaction at temperature that ranges from 750°C to 1100°C with different normalized stoichiometric ratio. The experimental results demonstrate that the addition of CaO increases the optimum denitration temperature to 1100°C, but it has no effect on normalized stoichiometric ratio. In the whole reaction process NH3 not only restores NO to O2 but also reacts with O2 to NO. Since the adsorption of NH3 on CaO surface, in the temperature range of 750°C-850°C the addition of CaO promotes the reaction of NH3 and O2 and increases NOX concentration. However, in the temperature range of 850°C-1000°C it not only promotes NH3 oxidation but also inhibits the reduction reaction of NH3, thereby the denitration reaction is inhibited. In the temperature range of 1050°C-1100°C the denitration reaction is promoted due to the NH3 desorption from CaO surface.

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Liu, Ya Qiong, Jia Zhen Du, Pi Qiang Tan, and Ai Min Du. "Progress on Denitration and Desulfuration Technologies for Marine Diesel Engines." Applied Mechanics and Materials 713-715 (January 2015): 51–56. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.51.

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Exhaust emission regulations issued by International Maritime Organization (IMO) for marine diesel engines are given and formation mechanisms for several pollutant emissions are introduced. Main denitration and desulfuration technologies for reducing NOx and SOx emissions are seperately summarized. In addition, working mechanism of different emission control technologies and their applications on marine diesel engines are introduced. These different emission control technologies are analyzed by evaluating conversion efficiency, economy and practical performance, and existed problems and future technologies are given. A Combination of different denitration and desulfuration technologies is a inevitable trend for emission reduction of marine diesel engines.

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Wang, Yuanqing, Guichen Zhang, and Juan Su. "Simultaneous Removal of SO2 and NO by O3 Oxidation Combined with Seawater as Absorbent." Processes 10, no. 8 (2022): 1449. http://dx.doi.org/10.3390/pr10081449.

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Aiming at NOx (NO 90%, NO2 10%) and SO2 in simulated vessel emissions, denitration and desulfurization were studied through ozone oxidation combined with seawater as absorbent. Specifically, the different influencing factors of denitration and desulfurization were analyzed. The results indicated that the oxidation efficiency of NO can reach over 90% when the molar ratio of O3/NO is 1.2. Ozone oxidation and seawater washing in the same unit can decrease the temperature of ozone oxidation of NO, avoid high temperature ozone decomposition, and enhance the oxidation efficiency of NO. When NO inlet initial concentration is lower than 800 ppm, the NOx removal efficiency can be improved by increasing NO inlet concentration, and when NO inlet initial concentration is greater than 800 ppm, increasing the concentration of NO would decrease the NOx removal efficiency. Increasing the inlet concentration of SO2 has minor effect on desulfurization, but slightly reduces the absorption efficiency of NOx due to the competition of SO2 and NOx in the absorption solution. Besides, final products (NO2−, NO3−, SO32−, and SO42−) were analyzed by the ion chromatography.

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Zhang, Lei, Chao Yang, Lei Zhang, et al. "Application of Plasma Treatment in Preparation of Soybean Oil Factory Sludge Catalyst and Its Application in Selective Catalytic Oxidation (SCO) Denitration." Materials 11, no. 9 (2018): 1609. http://dx.doi.org/10.3390/ma11091609.

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At present, the most commonly used denitration process is the selective catalytic reduction (SCR) method. However, in the SCR method, the service life of the catalyst is short, and the industrial operation cost is high. The selective catalytic oxidation absorption (SCO) method can be used in a low temperature environment, which greatly reduces energy consumption and cost. The C/N ratio of the sludge produced in the wastewater treatment process of the soybean oil plant used in this paper is 9.64, while the C/N ratio of the sludge produced by an urban sewage treatment plant is 10–20. This study shows that the smaller the C/N ratio, the better the denitration efficiency of the catalyst. Therefore, dried oil sludge is used as a catalyst carrier. The influence of different activation times, and LiOH concentrations, on catalyst activity were investigated in this paper. The denitration performance of catalysts prepared by different activation sequences was compared. The catalyst was characterized by Fourier Transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The experimental results showed that: (1) When the concentration of the LiOH solution used for activation is 15%, and the activation time is four hours, the denitration effect of the catalyst is the best; (2) the catalyst prepared by activation before plasma roasting has the best catalytic activity.

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Wang, Zongyu, Hailang Kuang, Jifeng Zhang, Lilin Chu, and Yulong Ji. "Nitrogen Oxide Removal by Coal-Based Activated Carbon for a Marine Diesel Engine." Applied Sciences 9, no. 8 (2019): 1656. http://dx.doi.org/10.3390/app9081656.

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Vanadium-based catalysts are mainly used for marine diesel exhaust denitration. However, their poor catalytic ability at low temperature and poor sulfur tolerance, as well as high toxicity and cost, are big turnoffs. AC (Activated carbon) exhibits good adsorption capacity and catalytic ability in denitration because of its high specific surface area and chemical activity. In this paper, coal-based AC was used for simulating diesel exhaust denitration in different conditions. The results show that the NO removal ability of AC is poor in an NO/N2 system. The NO2 removal ability is excellent in an NO2/N2 system, where NO is desorbed. The NOx removal efficiency is 95% when the temperature is higher than 200 °C in an NO2/NH3/N2 system. When the temperature is lower than 100 °C, AC can catalytically oxidize NO to NO2 in an NO2/O2/N2 system. The near-stable catalytic efficiencies of AC for a slow SCR (Selective Catalytic Reduction) reaction, a standard SCR reaction, and a fast SCR reaction at 300 °C are 12.1%, 31.6%, and 70.8%, respectively. When ships use a high-sulfur fuel, AC can be used after wet scrubber desulfurization to catalytically oxidize NO to NO2 at a low temperature. When ships use a low-sulfur fuel, AC can be used as a denitration catalyst at high temperatures.

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Chen, Wangsheng, Fali Hu, Linbo Qin, et al. "Mechanism and Performance of the SCR of NO with NH3 over Sulfated Sintered Ore Catalyst." Catalysts 9, no. 1 (2019): 90. http://dx.doi.org/10.3390/catal9010090.

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A sulfated sintered ore catalyst (SSOC) was prepared to improve the denitration performance of the sintered ore catalyst (SOC). The catalysts were characterized by X-ray Fluorescence Spectrometry (XRF), Brunauer–Emmett–Teller (BET) analyzer, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance infrared spectroscopy (DRIFTS) to understand the NH3-selective catalytic reduction (SCR) reaction mechanism. Moreover, the denitration performance and stability of SSOC were also investigated. The experimental results indicated that there were more Brønsted acid sites at the surface of SSOC after the treatment by sulfuric acid, which lead to the enhancement of the adsorption capacity of NH3 and NO. Meanwhile, Lewis acid sites were also observed at the SSOC surface. The reaction between −NH2, NH 4 + and NO (E-R mechanism) and the reaction of the coordinated ammonia with the adsorbed NO2 (L-H mechanism) were attributed to NOx reduction. The maximum denitration efficiency over the SSOC, which was about 92%, occurred at 300 °C, with a 1.0 NH3/NO ratio, and 5000 h−1 gas hourly space velocity (GHSV).

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Chen, Wangsheng, Dongping Huang, Bo Zhao, Fali Hu, Linbo Qin, and Shijie Wang. "Kinetics Analysis of the NH3-SCR Denitration Reaction over Sintered Ore Catalysts." Energies 15, no. 13 (2022): 4522. http://dx.doi.org/10.3390/en15134522.

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Utilizing sintered ore catalysts (SOC), which are used in the sintering industry for NH3-SCR denitration, is a feasible and economical way to reduce NOx emission in sintering flue gas. Therefore, in order to enhance the denitration efficiency of SOC, sintered ore modified by sulfuric acid and sulfated sintered ore catalysts (SSOC-5) were prepared. Kinetic analyses of these two catalysts for denitration were carried out in this study. On the basis of eliminating the influence of internal and external diffusion, the relationship between reactants and reaction rate was studied by a power function kinetic model. This clarified that the adsorption ability of the acid-modified catalyst for reaction gas adsorption was stronger than that of sintered ore catalysts, and the reaction rate was also accelerated. The NO, NH3 and O2 reaction orders of SOC were 1, 0.3 and 0.16 at 250~300 °C, while these values of SSOC-5 were 0.8, 0.06 and 0.09, respectively. The apparent activation energy of SOC was 83.66 kJ/mol, while the value of SSOC-5 decreased to 59.93 kJ/mol.

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Ma, Mingxuan, Xiaoyu Ma, Suping Cui, Tingting Liu, Yingliang Tian, and Yali Wang. "Low Temperature NH3-SCR over Mn-Ce Oxides Supported on MCM-41 from Diatomite." Materials 12, no. 22 (2019): 3654. http://dx.doi.org/10.3390/ma12223654.

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A series of MCM-41 molecular sieves with different molar ratio of template to silicon were synthesized through hydrothermal synthesis method by using cetyltrimethylammonium bromide (CTAB) as the template, diatomite as the silicon source. By using impregnation method, the Mn-Ce/MCM-41 SCR molecular sieve-based catalysts were prepared. The results observed that when the molar ratio of template to silicon was 0.2:1, the MCM-41 as catalyst carrier has the highest surface area and largest pore volume, it also presented typically ordered hexagonal arrays of uniform channels. The denitration catalytic material based on this carrier has a high number of Lewis acidic sites, and the denitration efficiency can reach more than 93%.

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Wang, Zongyu, Hailang Kuang, Jifeng Zhang, Lilin Chu, and Yulong Ji. "Experimental Study on the Removal of Real Exhaust Pollutants from a Diesel Engine by Activated Carbon." Applied Sciences 9, no. 15 (2019): 3175. http://dx.doi.org/10.3390/app9153175.

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So far, most of the experimental researchers studying the removal of diesel exhaust pollutants have done so with simulated exhaust gas, which cannot demonstrate the ability of catalysts accurately. Because activated carbon (AC) has low price, no secondary pollution, good adsorption performance, and certain catalytic activity, it has good application prospects in the field of marine exhaust pollutant removal. In this paper, the removal of particulate matter (PM), carbon monoxide (CO), and NOx from real exhaust gas by AC was studied. The results show that PM removal efficiency reached up to 77%, while the pressure drop increased with running time. AC may degenerate to some extent with the increase of temperature, resulting in a negative removal efficiency of CO. The denitration efficiency of AC was up to 34.5% without urea, and further increased to 44.8% after spraying urea, still a distance from industrial applications. In the future, it may be necessary to install a fan to compensate the reactor or to backwash the reactor to avoid excessive pressure drop. The thermal stability of the AC also needs to be improved. To increase the denitration performance, it may be helpful to modify the AC or impregnate other metal oxides.

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Omirgali, A. K., Kh A. Yussupov, S. B. Aliev, E. Kh Aben, and D. K. Akhmetkhanov. "IMPROVING THE EFFICIENCY OF DENITRATION OF SORBENT SOLUTION IN URANIUM GEOTECHNOLOGY." Ugol', no. 04 (April 8, 2022): 72–76. http://dx.doi.org/10.18796/0041-5790-2022-4-72-76.

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Wang, Guilin, Yigang Zhou, Yue Zhao, and Sen Wang. "Operation optimization of SCR system based on denitration efficiency prediction model." IOP Conference Series: Earth and Environmental Science 300 (August 9, 2019): 032088. http://dx.doi.org/10.1088/1755-1315/300/3/032088.

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Hu, Bin, Cong Chen, Shouxi Jiang, Xiaosong Liu, and Qianjin Dai. "Investigating the Optimization Design of Internal Flow Fields Using a Selective Catalytic Reduction Device and Computational Fluid Dynamics." Energies 15, no. 4 (2022): 1451. http://dx.doi.org/10.3390/en15041451.

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Selective catalytic reduction (SCR) and denitrification are the best technologies for nitrogen oxides (NOx) control in coal-fired power plants, and their denitration efficiency and ammonia escape rate are closely related to their internal flow characteristics. By adding a deflector to the SCR device, the flow field in the curve can be effectively improved, and the stable and efficient operation of the SCR device can be realized. Based on the numerical simulation method, the SCR system of a coking coal-fired boiler in a steel plant was simulated using k-ε (the turbulence model), and three design schemes of deflectors were proposed and numerically simulated simultaneously. After optimization, the ammonia injection grid’s downstream velocity variance coefficient CV was 6.69, the catalyst upper cross-section velocity variance coefficient was 11.84, the cross-sectional temperature average was 499 K, the maximum temperature deviation was 9 °C, the maximum-to-minimum temperature interval span was 15 °C, the cross-sectional NH3/NOx molar ratio average value was 0.8122, the coefficient of variance was 4.67, and the pressure loss was 1855 Pa. The findings of this work will help improve the denitration efficiency and provide an important reference for the actual transformation design.

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Gou, Xiang, Kai Zhang, Lian Sheng Liu, et al. "Study on Noble Metal Catalyst for Selective Catalytic Reduction of NOx at Low Temperature." Applied Mechanics and Materials 448-453 (October 2013): 885–89. http://dx.doi.org/10.4028/www.scientific.net/amm.448-453.885.

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The method of selective catalytic reduction (SCR) to removal NOx is very mature. However, its initial investment and operation cost are still high, which limits the development of SCR technology. Low temperature SCR catalysts can significantly reduce the cost. Catalyst active component and its carrier is the key to the efficiency of denitration. This paper summarizes the research progress of noble metal catalyst of low temperature SCR.

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Meng, Zhaolei, Chao Zhu, Jian Wang, and Wenfei Wu. "Comparative Study on NH3-SCR of High Entropy Mineral Catalytic Materials for Different Ratios of Rare Earth Concentrate/Rare Earth Tailing." Polish Journal of Chemical Technology 22, no. 3 (2020): 70–78. http://dx.doi.org/10.2478/pjct-2020-0030.

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AbstractA series of high-entropy mineral catalytic materials were obtained by mixing rare earth tailings containing Fe oxide and rare earth concentrate rich in Ce in Baiyun Obo in different proportions, and by acid-base leaching and microwave roasting. The effects of different proportions of mixed rare earth minerals on the denitrification activity of the samples were analyzed by various techniques, including XRD, EDS and SEM. The mineral phase structure and surface morphology of the catalysts were analyzed. The surface properties of the samples were tested by TPD and XPS methods. The denitrification activity of the sample was simultaneously evaluated and compared in the microreactor. The results show that the denitration efficiency of the active powder is the best when the mixing ratio of rare earth tailings/rare earth concentrate is 1:1, the denitration rate can reach 82%. In summary, different proportions of optimization are extremely effective methods to improve catalyst performance.

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Li, Ruo Han, Song Zhou, Cai Ling Li, Zhi Yu Wang, and Yuan Qing Zhu. "A Study on SCR Catalyst Support." Advanced Materials Research 726-731 (August 2013): 17–20. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.17.

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NOx is one of the most serious atmosphere pollutants, and how to control and remove NOx is the hot research in the environmental field all over the world. SCR is considered as one of the most effective denitration methods at present. In SCR technology, catalyst is the core of the SCR system, and the performance of SCR catalyst mainly depends on the active component and catalyst support. Catalyst support can not only affect the choice of the active material and the catalyst promoter, but also affect the flue gas denitration efficiency. This paper mainly introduces four kinds of SCR catalyst supports: TiO2, Al2O3, activated carbon and activated carbon fiber and ZSM-5 zeolite. The performance of the four types of catalyst supports are compared, and SCR activity test of Mn-Ce supported and V2O5 supported on different catalyst supports are conducted respectively. Finally, for Mn-Ce supported and V2O5 supported catalysts, this paper puts forward that TiO2 is the most widely used and effective catalyst support.

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Xiao, Haiping, Chaozong Dou, Hao Shi, Jinlin Ge, and Li Cai. "Influence of Sulfur-Containing Sodium Salt Poisoned V2O5–WO3/TiO2 Catalysts on SO2–SO3 Conversion and NO Removal." Catalysts 8, no. 11 (2018): 541. http://dx.doi.org/10.3390/catal8110541.

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A series of poisoned catalysts with various forms and contents of sodium salts (Na2SO4 and Na2S2O7) were prepared using the wet impregnation method. The influence of sodium salts poisoned catalysts on SO2 oxidation and NO reduction was investigated. The chemical and physical features of the catalysts were characterized via NH3-temperature programmed desorption (NH3-TPD), H2-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR). The results showed that sodium salts poisoned catalysts led to a decrease in the denitration efficiency. The 3.6% Na2SO4 poisoned catalyst was the most severely deactivated with denitration efficiency of only 50.97% at 350 °C. The introduction of SO42− and S2O72− created new Brønsted acid sites, which facilitated the adsorption of NH3 and NO reduction. The sodium salts poisoned catalysts significantly increased the conversion of SO2–SO3. 3.6%Na2S2O7 poisoned catalyst had the strongest effect on SO2 oxidation and the catalyst achieved a maximum SO2–SO3-conversion of 1.44% at 410 °C. Characterization results showed sodium salts poisoned catalysts consumed the active ingredient and lowered the V4+/V5+ ratio, which suppressed catalytic performance. However, they increased the content of chemically adsorbed oxygen and the strength of V5+=O bonds, which promoted SO2 oxidation.

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Поляков, В. Г., С. О. Ященко, Э. Р. Ганиев, Д. С. Ишкулов та Е. С. Кашина. "Инновационные технологические решения обеспечения экологической безопасности и экономической эффективности печного производства строительных материалов". Journal of Applied Research, № 5 (19 травня 2025): 104–10. https://doi.org/10.47576/2949-1878.2025.5.5.015.

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Внедрение инновационных технологий в промышленном производстве и строительстве является залогом успешного экологически устойчивого экономического роста. Многие российские предприятия цементной промышленности перешли на новые технологии охраны окружающей среды и активно приступили к внедрению систем денитрации SCR (Selective Catalytic Reduction – метод снижения содержания в отработавших газах опасных оксидов азота). Указанный технологический процесс, однако, имеет некоторые ограничения, не позволяющие добиваться высокой результативности установки и ее экономической эффективности. Представлены инновационные технологические картриджные решения, позволяющие преодолеть проблемы высокой концентрации пыли, засорения катализатора в реакторе, регулирования оптимальной температуры денитрации катализатора, высокого содержания щелочного металла в дымовых газах цементных печей и др. The introduction of innovative technologies in industrial production and construction is the key to successful environmentally sustainable economic growth. Many Russian enterprises in the cement industry have switched to new environmental protection technologies and have actively begun to implement SCR denitration systems (Selective Catalytic Reduction – a method for reducing the content of hazardous nitrogen oxides in exhaust gases). This technological process, however, has some limitations that do not allow achieving high efficiency of the installation and its economic efficiency. The paper presents innovative technological cartridge solutions that allow overcoming the problems of high dust concentration, catalyst clogging in the reactor, regulating the optimal catalyst denitration temperature, high alkali metal content in the flue gases of cement kilns, etc.

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Chen, Ying, Hongwei He, Shaohua Wu, et al. "Mn/Ce Oxides Decorated Polyphenylene Sulfide Needle-Punching Fibrous Felts for Dust Removal and Denitration Application." Polymers 12, no. 1 (2020): 168. http://dx.doi.org/10.3390/polym12010168.

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Development of a novel filter material is urgently required for replacing the high-cost flue gas purification technology in the simultaneous removal of both fine dust and Nitrogen oxides (NOx). In this study; polyphenylene sulfide (PPS) needle-punching fibrous felts (NPFF) were employed as the filter material to remove the fine dust; and in the meanwhile; Mn and Ce oxides were loaded onto the PPS NPFF as the catalyst for selective catalytic reduction of NOx with NH3. Two different pretreatment methods; i.e., sodium alginate (SA) deposition and plasma treatment; were employed to modify the PPS NPFF before the traditional impregnation and thermal treatment processes during the catalyst loading. The results showed that these two pretreatment methods both afforded the PPS NPFF with the enhanced loading rate and stability of Mn/Ce oxides compared to those without any pretreatments; which were significantly beneficial for the denitration application. Moreover; we found that both SA deposition and plasma pre-treated samples presented excellent dust-removal properties; and the filtration efficiency could reach 100% when the particle size of the fine particulates was above 4 μm. This study demonstrated that our Mn/Ce oxides decorated PPS NPFF have great potential to be applied in the fuel gas purification field; due to their stable structure; handling convenience; and excellent filtration efficiency; as well as high denitration performance.

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Wang, Zongyu, Hailang Kuang, Jifeng Zhang, et al. "Diesel engine exhaust denitration using non-thermal plasma with activated carbon." Reaction Chemistry & Engineering 5, no. 9 (2020): 1845–57. http://dx.doi.org/10.1039/d0re00227e.

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A diesel engine de-NOx system combining non-thermal plasma and activated carbon was set up. The de-NOx efficiency reaches 91.8% and 92.5% for simulated gas and real exhaust gas, respectively. It has good potential to replace vanadium-based SCR.

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Xu, Guangwen, Bing Wang, Hironori Suzuki, et al. "Removal Efficiency of the Combined Desulfurization/Denitration Process Using Powder-Particle Fluidized Bed." JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 32, no. 1 (1999): 82–90. http://dx.doi.org/10.1252/jcej.32.82.

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Song, Bo, Zhenxing Shen, Zitong Wang, et al. "Resource utilization of red mud with biochar to prepare high-efficiency denitration catalysts." Journal of Cleaner Production 502 (April 2025): 145386. https://doi.org/10.1016/j.jclepro.2025.145386.

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Gong, Pijian, and Xinxue Li. "Promoting Effect of H+ and Other Factors on NO Removal by Using Acidic NaClO2 Solution." Energies 12, no. 15 (2019): 2966. http://dx.doi.org/10.3390/en12152966.

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In this study, NaClO2 was selected as a denitration oxidant. In order to clarify the mechanism of NaClO2 as an oxidation agent for NO removal efficiency, the effects of H+ and other factors (NaClO2 concentration, temperature, and the other gas) on the NO removal efficiency were investigated. NaClO2 showed a promotional ability on NO removal, whose efficiency increased with the increase of NaClO2 concentration. One hundred percent removal efficiency of NO could be achieved when the NaClO2 concentration was 0.014 mol/L. Furthermore, raising the reaction temperature benefited the removal of NO. The lower the pH, the better the NO removal efficiency. The promoting effect of H+ on the NO removal was studied by the Nernst equation, ionic polarization, and the generation of ClO2. Under the optimal conditions, the best removal efficiency of NO was 100%. Based on the experimental results, the reaction mechanism was finally speculated.

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Liu, Zhang Xian, Pei Pei Sun, Song Tao Chen, and Li Juan Shi. "Research on Mercury Emissions Regularity and Adsorbing Mercury by Activated Carbon in Coal-fired Power Plants." Advanced Materials Research 284-286 (July 2011): 301–4. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.301.

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The coal-fired power plant is the main anthropogenic source of mercury pollution. The mercury in flue gas exists as elemental mercury(Hg0), oxidizing state mercury(Hg2+) and particulate mercury(Hgp). Mercury speciation distribution in flue gas was influenced and controled by the factors including conditions of ignition, desulphurization or denitration and Based on the investigation of coal-fired power plant technologies of removing Hg, this research uses the modified activated carbon (MAC) and studies its removal efficiency. Result indicates that the uptake of Hg by MAC was﹥90%.

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Yang, Qiao Wen, Yan Jiao Ren, Lu Wei Zhao, Jin Lei Zuo, and Wen Yi Sun. "Development of Catalyst for Industrial Flue Gas Denitration at Low Temperature." Applied Mechanics and Materials 535 (February 2014): 683–87. http://dx.doi.org/10.4028/www.scientific.net/amm.535.683.

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The most effective technology currently for flue gas denitrition is selective catalytic reduction (SCR). And the major problem against spreading SCR technology is the high cost and low efficiency of the catalyst for SCR. Al2O3 supported Mn-Fe oxide precursor was prepared through water/ethanol coprecipitation and then nitridized through NH3-TPD. Thus the inexpensive and efficient Mn-Fe-O-N/Al2O3 catalyst was obtained. The catalyst with a Mn/Al molar ratio of 0.4 and a Fe loading of 6.0 wt.% was testified to have the best performance for denitrition. The NOx conversion reached 95% at low temperature (150~200°C).

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Li, Haoyang, Zhihai Cheng, Fangqin Li, Hufei Zhou, and Jianxing Ren. "Denitration Simulation of SNCR System Nozzles at Different Layout Positions in Coal Powder Boilers." E3S Web of Conferences 520 (2024): 03006. http://dx.doi.org/10.1051/e3sconf/202452003006.

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Building a clean, low-carbon, safe and efficient energy system is an overall requirement for the modernization of the energy system, The nitrogen oxides produced by the combustion of fossil fuels need to be effectively treated. The selective non-catalytic reduction denitrification (SNCR) technology in the thermal power industry. It is widely used due to its low cost and mature technology. By using CFD software to simulate and study the coupling of flue gas temperature field and NO concentration field, the SNCR nozzle was set up to study the impact on denitrification efficiency. Simulate multiple layout methods, including sequential arrangement, staggered arrangement, concentrated in the middle and concentrated on both sides. The denitrification efficiency is highest among them, which is concentrated on both sides and further optimized through the NO concentration field in the furnace. After optimization, the denitrification efficiency reached 59.2%, which was 2.4% higher than the traditional uniform layout method. It has important practical guidance significance for energy conservation, emission reduction, and operational optimization.

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Ma, Dong Zhu, Jian Li, Ling Zhang, Peng Guo, Zi Qiang Wen, and Li Jiang Guo. "Denitrification Activities of Mg-Mo-V-Ti Catalysts Prepared by Dipping Method at Low Temperature." Materials Science Forum 913 (February 2018): 893–99. http://dx.doi.org/10.4028/www.scientific.net/msf.913.893.

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Mg-Mo-V-Ti catalysts of low temperature denitrification were prepared by dipping method. In order to study the activity of selective catalytic reduction, the catalyst was placed in a fixed bed reactor. Industrial flue gas was simulated with cylinder gas. Results indicate that the 0.1wt% content of MgO catalyst has good performance on denitration activity and sulfur resistance. The effects of oxygen content, space velocity and reaction temperature on the activity of the 0.1MgO-6MoO3-3V2O5-TiO2 wt% catalyst were investigated. With the increase of oxygen concentration, the denitrification efficiency increases when the oxygen concentration is less than 8%. When the oxygen content is greater than 8%, the denitrification efficiency is almost the same. The denitrification efficiency decreases with the increase of space velocity. The removal efficiency of NO 0.1MgO-6MoO3-3V2O5-TiO2 wt% catalyst over increases first and then becomes stable with the increase of temperature, and the conversion efficiency of SO2 is less than or equal to 2.2% at 120~240 °C.

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Gu, Jialiang, Rudi Duan, Weibin Chen, Yan Chen, Lili Liu, and Xidong Wang. "Promoting Effect of Ti Species in MnOx-FeOx/Silicalite-1 for the Low-Temperature NH3-SCR Reaction." Catalysts 10, no. 5 (2020): 566. http://dx.doi.org/10.3390/catal10050566.

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Manganese and iron oxides catalysts supported on silicalite-1 and titanium silicalite-1 (TS-1) are synthesized by the wet impregnation method for the selective catalytic reduction (SCR) of NOx with NH3 (NH3-SCR), respectively. The optimized catalyst demonstrates an increased NOx conversion efficiency of 20% below 150 °C, with a space velocity of 18,000 h−1, which can be attributed to the incorporation of Ti species. The presence of Ti species enhances surface acidity and redox ability of the catalyst without changing the structure of supporter. Moreover, further researches based on in situ NH3 adsorption reveal that Lewis acid sites linked to Mn4+ on the surface have a huge influence on the improvement of denitration efficiency of the catalyst at low temperatures.

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Yang, Ke, Weiwei Xiao, Quan Xu, et al. "Reaction and Characterization of Low-Temperature Effect of Transition Nanostructure Metal Codoped SCR Catalyst." Journal of Nanomaterials 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/7901686.

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Typical p-type semiconductor MnOx codoped with n-type semiconductors such as CeO2 and V2O5 was reported to achieve high efficiency in catalytic NOx removal by NH3. In this paper, we present novel Mn-Ce codoped V2O5/TiO2 catalyst which exhibited an excellent NO conversion efficiency of 90% at 140°C. By using this codoped catalyst, the best low-temperature activity was greatly decreased when compared with single Mn- or Ce-doped catalyst. According to the characterization results from BET, XRD, and XPS, the codoped catalyst was composed of both CeO2 and amorphous Mn. The electron circulation formed between doping elements is believed to promote the electron transfer, which may be one of the reasons for excellent low-temperature denitration performance.

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Wang, Wen Yong, and Xiao Juan Ma. "Study on the Countermeasures of NO_x Emission Reduction in Chengdu Economic Circle." Advanced Materials Research 726-731 (August 2013): 2324–32. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.2324.

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Based on the detailed survey on the source and volume of NOx emission over Chengdu Economic Circle, the third-generation air quality model CMAQ is adopted for simulating the density of NOx in the air over Chengdu Economic Circle. The result shows that the hourly concentration, daily mean concentration and annual mean concentration of NOx in air exceed the standard data, and the affected areas respectively account for 0.2%, 0.18% and 0.12% of the total area of the economic circle. Meanwhile, in accordance with the simulation calculation, The NOX emission of the vehicle exhaust, the thermal power plant and the cement plant are the major NOX concentration contribution sources in air, contribution rate is amounting to 39.13%, 21.41% and 15.34% respectively. Thus, three main measures to reduce the emission of NOx of Chengdu Economic Circle are proposed as follows: firstly, strengthen the management of vehicle and reduce the emission of NOx by the vehicle; secondly, manage the NOx of the industrial enterprise; flue gas denitrification equipment must be constructed in the thermal power plant and cement manufacturing enterprise, and the comprehensive denitration efficiency of the thermal power plant should be not less than 70% and the comprehensive denitration efficiency of the cement plant should not be less than 60%; thirdly, joint prevention and control measures should be implemented between the cities, so as to reduce the transport of NOx. With the application of the above measures, the emission reductions of NOx can be reduced to 55% of the existing volume, and the concentration of NOx in the air can meet with the Class II of national ambient air quality Standard.

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Li, Chen, Su Ping Cui, Xian Ce Meng, Zhen Guo Peng, Xian Zheng Gong, and Yu Liu. "Potentials for Denox in Chinese Cement Industry with the Life Cycle Assessment Method." Materials Science Forum 814 (March 2015): 470–75. http://dx.doi.org/10.4028/www.scientific.net/msf.814.470.

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To explore NOx mitigation strategies in Chinese cement industry systematically, a material flow analysis was developed. The realistic output of cement production in China were identified and quantified. The inventory data of Chinese cement production were selected without denitration technology applications at that time. Then the life cycle impact assessment (LCIA) results were calculated with the principal of ISO 14040 and ISO 14044 of Life Cycle Assessment. The impact categories of global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), photochemical oxidant formation potential (POCP), and human toxicity potential (HTP) were used to calculate environmental impact. The results showed that the NOx emission was the major environmental damages and the following was CO2 emission. This argument disagreed with the view that CO2 emission was the major contributor of environmental load. The reason is that the NOx emission is far over the international level due to few denitration technology applications. In the assumption of selective non-catalytic reduction (SNCR) technology applications, there is still large emission mitigation potential according to the target scenario analysis. The application of selective catalytic reduction (SCR) technology with higher deNOx efficiency and the roadmap of deNOx of Chinese cement industry were also discussed. The SNCR technology with the auxiliary of SCR development over the coming decades will be decisive for the roadmaps of Chinese cement industry to reach deeper NOx emission cuts.

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Bai, Chuanxin, Kai Liu, Tong Zhao, and Jinjin Liu. "Study on Spray Characteristics and Breakup Mechanism of an SCR Injector." Applied Sciences 12, no. 18 (2022): 9387. http://dx.doi.org/10.3390/app12189387.

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Selective catalytic reduction (SCR) is currently one of the most efficient denitration technologies to reduce nitrogen oxide (NOx) emissions of diesel engines. AdBlue (urea water solution, UWS) is the carrier of the reducing agent of SCR, and the spray process of UWS is one of the critical factors affecting denitration efficiency. In this paper, a non-air-assisted pressure-driven full process spray (NPFPS) model is proposed to illustrate the breakup mechanism and the spray distribution properties of UWS through computational fluid dynamics (CFD). In the NPFPS model, the mechanism of the primary breakup is described by the volume of fluid (VOF) approach, which realizes the quantitative study of the critical parameters determining spray characteristics such as the breakup length, inclination angle, droplet size of the primary breakup, and primary velocity. The distribution of the spray after the primary breakup is depicted by the discrete phase model (DPM) coupled with the Taylor analogy breakup (TAB) model, through which the degree of secondary breakup can be obtained including quantitative studies of the droplet size distribution and velocity distribution in the different cross-sections. To verify the accuracy and feasibility of the NPFPS model, the experimental data are employed to compare with the simulation data. The results are in good agreement, which indicate the practical value of the model.

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Feng, Qihong, Junfeng Zhang, Chuan Peng, and Zhuojian Cai. "Synthesis of modified sludge biochar for flue gas denitration: Biochar properties, synergistic efficiency and mechanism." Waste Management 170 (October 2023): 204–14. http://dx.doi.org/10.1016/j.wasman.2023.08.007.

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Journal articles on the topic 'Denitration efficiency'

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