Comparison of NOx Emissions Decreasing Methods for Biofuel Boilers

2017 ◽  
Author(s):  
Titas Sereika ◽  
Kęstutis Buinevičius ◽  
Adolfas Jančauskas
Keyword(s):  
Catalytic Reduction ◽  
Nox Reduction ◽  
Main Idea ◽  
Nox Emissions ◽  
Reduction Methods ◽  
Reduction Of Nox ◽  
Secondary Air ◽  
Nitrogen Oxides Reduction ◽  
Gas Recirculation ◽  
Co Emission

The main idea of research is to figure out the emissions of nitrogen oxides reduction using various type of reduction methods. In experiments were used NOx reduction methods: high CO emissions generation, flue gas recirculation, water and water vapor supply, selective non-catalytic reduction (SNCR), and SNCR with flammable additive. This study presents emission and combustion results obtained burning furniture production waste which generates higher rate of NOx emissions. The result of research shows, that CO emission has the biggest impact factor -on reducing NOx emission. Burning fuel in combustion zone with first and secondary air ratio (40/60) and using methods for higher generation CO emissions reached 3.000 mg/m3 which reduces NOx emissions up to 83%. Using selective non-catalytic reduction with traditional and flammable additives reduction of NOx emissions reached up to 55%.

scholarly journals Experimental Study on the Catalytic Reduction of NOX by Fe and Ce During the Coke Combustion Process

2021 ◽  
Vol 290 ◽  
pp. 01032
Author(s):  
Qi Wang ◽  
Song Yang ◽  
Shoujun Liu ◽  
Lili Chen ◽  
Tingting Jiao ◽  
...  
Keyword(s):  
Catalytic Reduction ◽  
Nox Reduction ◽  
Combustion Process ◽  
Reduction Rate ◽  
Nox Emissions ◽  
Co Doping ◽  
Different Temperatures ◽  
Coke Combustion ◽  
Reduction Of Nox ◽  
Metal Additives

NOX emissions during the combustion of coal would cause serious pollution to the atmosphere. It is particularly important to reduce NOX pollution during the combustion process by replacing loose coal with clean coke. The use of clean coke for civil is one of the main ways to reduce NOX emissions, which is mainly formed by the mixed dry distillation of metal additives and coal. The coke samples with different proportions of metal additives were prepared by physical mixing method, and the NOX emission law of clean coke at different temperatures was studied in a high-temperature tube furnace reactor. The results show that the addition of Fe alone has a significant effect on the control of NOX emissions, and the co-doping with Ce can further promote the reduction of NOX, so as to achieve the final low emission of NOX. While the reaction temperature is 1000 ℃ and the addition ratio is 2:1, the NOX reduction rate is 73%. It has important practical value and scientific significance for the clean utilization of coal and the treatment of NOX in the atmosphere.

scholarly journals Reduction of Major Pollutants via Air-staged Commbustion on Burner System

2013 ◽  
Vol 64 (1) ◽  
Author(s):  
Mohammad Nazri Mohd. Jaafar ◽  
Mohd Nur Hanafi Zaini
Keyword(s):  
Combustion Process ◽  
Primary Concern ◽  
Nox Emissions ◽  
Percent Reduction ◽  
Secondary Air ◽  
Secondary Zone ◽  
Combustion Processes ◽  
Different Gases ◽  
Air Staging ◽  
Co Emission

Emission from the combustion processes can cause adverse effect to the environment.  The formation of pollutants such as NOx, CO, CO2 and SOx are hazardous and harmful to the ecosystem.  The awareness about the pollution due to the combustion activities, particularly in industrial field has set off an effort to find more comprehensive and enhanced technologies to reduce these pollutants.  There are several methods that can be used to reduce the emissions of these pollutants either by combustion modifications or post combustion treatment.  In this research, the method used is the post combustion treatment, i.e. the air staging method.  By air staging techniques, some of the combustion air will be directed into the primary combustion zone, while the remaining air is directed into the secondary zone.  The function of the secondary air is to reduce the peak flame temperatures, which theoretically reduce the emissions of NOx emissions.  The primary concern for this research is to study the effectiveness of the air staging in reducing NOx, CO, SO2, and UHC emissions from the combustion process.  The results obtained showed significant reduction in all major pollutants, i.e., a 31.8 percent reduction for CO emission, 16.8 percent for NOx, 12.7 percent for SO2 and 10.3 percent for UHC.  These reductions were obtained at different equivalence ratios for different gases.

Selective Catalytic Reduction of NOx Emissions

2021 ◽  
pp. 1115-1130
Author(s):  
R. J. G. Nuguid ◽  
F. Buttignol ◽  
A. Marberger ◽  
O. Kröcher
Keyword(s):  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Nox Emissions ◽  
Reduction Of Nox

Reduction of NOx emissions with low viscous biofuel using exhaust gas recirculation technique

2020 ◽  
Author(s):  
Rajasekar Rajendran ◽  
J. Paul Udayan Gomez ◽  
M. Mohammed Javed ◽  
Ganesan Subbiah
Keyword(s):  
Exhaust Gas Recirculation ◽  
Nox Emissions ◽  
Exhaust Gas ◽  
Reduction Of Nox ◽  
Gas Recirculation

scholarly journals In Situ DRIFTS Studies of NH3-SCR Mechanism over V2O5-CeO2/TiO2-ZrO2 Catalysts for Selective Catalytic Reduction of NOx

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1307 ◽  
Author(s):  
Yaping Zhang ◽  
Xiupeng Yue ◽  
Tianjiao Huang ◽  
Kai Shen ◽  
Bin Lu
Keyword(s):  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Nox Reduction ◽  
Oxygen Storage ◽  
In Situ Drifts ◽  
Nh3 Scr ◽  
Nh3 Adsorption ◽  
Reduction Of Nox ◽  
Zro2 Catalyst

TiO2-ZrO2 (Ti-Zr) carrier was prepared by a co-precipitation method and 1 wt. % V2O5 and 0.2 CeO2 (the Mole ratio of Ce to Ti-Zr) was impregnated to obtain the V2O5-CeO2/TiO2-ZrO2 catalyst for the selective catalytic reduction of NOx by NH3. The transient activity tests and the in situ DRIFTS (diffuse reflectance infrared Fourier transform spectroscopy) analyses were employed to explore the NH3-SCR (selective catalytic reduction) mechanism systematically, and by designing various conditions of single or mixing feeding gas and pre-treatment ways, a possible pathway of NOx reduction was proposed. It was found that NH3 exhibited a competitive advantage over NO in its adsorption on the catalyst surface, and could form an active intermediate substance of -NH2. More acid sites and intermediate reaction species (-NH2), at lower temperatures, significantly promoted the SCR activity of the V2O5-0.2CeO2/TiO2-ZrO2 catalyst. The presence of O2 could promote the conversion of NO to NO2, while NO2 was easier to reduce. The co-existence of NH3 and O2 resulted in the NH3 adsorption strength being lower, as compared to tests without O2, since O2 could occupy a part of the active site. Due to CeO2’s excellent oxygen storage-release capacity, NH3 adsorption was weakened, in comparison to the 1 wt. % V2O5-0.2CeO2/TiO2-ZrO2 catalyst. If NOx were to be pre-adsorbed in the catalyst, the formation of nitrate and nitro species would be difficult to desorb, which would greatly hinder the SCR reaction. All the findings concluded that NH3-SCR worked mainly through the Eley-Rideal (E-R) mechanism.

Numerical Study on NOx Reduction in Pulse Detonation Combustion by Using Steam Injection Decoupled From Detonation Development

2018 ◽  
Author(s):  
Niclas Hanraths ◽  
Fabian Tolkmitt ◽  
Phillip Berndt ◽  
Neda Djordjevic
Keyword(s):  
Initial Conditions ◽  
Numerical Study ◽  
Nox Reduction ◽  
Pollutant Emissions ◽  
Nox Emissions ◽  
Reliable Operation ◽  
Detonation Cell ◽  
Pulse Detonation ◽  
Detonation Combustion ◽  
Reduction Methods

Recently, the focus has been laid on the characteristics of pollutant emissions from pulse detonation combustion. Initial studies indicate possibly high nitrogen oxides (NOx) emissions, so the assessment of potential primary reduction methods is advisable. The present work considers the following reduction methods: lean combustion, nitrogen and steam dilution as well as flue gas recirculation. Since such changes in the combustion mixture reduce its reactivity and thus detonability, they can impair a reliable operation in technical systems. In order to explore the potential and limitations of each of these reduction methods, they are compared for mixtures featuring an identical characteristic detonation cell size at given initial conditions. Furthermore, building upon the use of steam dilution, a modified method to add steam to the combustible mixture is investigated. In order to avoid the strong reduction of mixture detonability by steam addition and ensure a robust detonation formation, steam is injected into the already developed detonation front. It was found that, for sufficiently even steam distribution, NOx reduction comparable to a premixed dilution could be achieved. This approach enables the realization of NOx reduction in pulse detonation combustion also for such conditions, for which premix dilution is not feasible. Therefore, combining the premix dilution with post-shock injection offers a promising strategy to substantially reduce NOx emissions from pulse detonation combustion, while at the same time ensuring its reliable operation.

scholarly journals An overview on metal-oxide catalytic converters

2020 ◽  
Vol 30 (1) ◽  
pp. 1-7
Author(s):  
Ecaterina–Magdalena MODAN ◽  
◽  
Adriana-Gabriela PLAIASU
Keyword(s):  
Carbon Monoxide ◽  
Nitrogen Oxides ◽  
Selective Catalytic Reduction ◽  
Air Pollutants ◽  
Environmental Problem ◽  
Catalytic Reduction ◽  
Nox Emissions ◽  
Catalytic Converters ◽  
Diesel Vehicles ◽  
Reduction Of Nox

Diesel vehicles produce exhaust gases that include nitrogen oxides (NOx), carbon monoxide and hydrocarbons.A major environmental problem is the elimination of nitrogen oxides, as they are major air pollutants. Global restrictions on NOx emissions from fuel combustion have been imposed. Efforts have been made to develop catalysts for the selective catalytic reduction of NOx. In this paper is presented the types of catalytic converters used nowadays for dissipate emissions and selective catalytic reduction.

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