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.

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%.

A System of Selective Non Catalytic Reduction of NOx for Diesel Engine

2011 ◽  
Vol 201-203 ◽  
pp. 643-646 ◽  
Author(s):  
Bo Yan Xu ◽  
Hai Ying Tian ◽  
Jie Yang ◽  
De Zhi Sun ◽  
Shao Li Cai
Keyword(s):  
Catalytic Reduction ◽  
Three Dimensional ◽  
Exhaust Gas ◽  
Test Results ◽  
Practical Application ◽  
Three Dimensional Model ◽  
Reduction Efficiency ◽  
Different Temperatures ◽  
Reduction Of Nox ◽  
Good Agreement

SNCR (Selective Non Catalytic Reduction) system is proposed, with 40% methylamine aqueous solution as reducing agent to reduce NOx in diesel exhaust gas. The effect of injection position and volume on the reduction efficiency through the test bench is systematically researched. A three-dimensional model of a full-sized diesel SNCR system generated by CFD software FIRE is used to investigate the reduction efficiency under different temperatures. The simulated results have a good agreement with the test results, and it can be used to optimize SNCR system. The results can indicate the practical application of this technology.

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

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.

Humid Air NOx Reduction Effect on Liquid Fuel Combustion

2004 ◽  
Vol 126 (1) ◽  
pp. 69-74 ◽  
Author(s):  
A. G. Chen ◽  
Daniel J. Maloney ◽  
William H. Day
Keyword(s):  
Liquid Fuel ◽  
Nox Reduction ◽  
Flame Temperature ◽  
Substantial Reduction ◽  
Combustion Process ◽  
Pollutant Emissions ◽  
Humid Air ◽  
Wide Range ◽  
Reduction Of Nox ◽  
Reduction Effect

An experimental investigation was carried out at DOE NETL on the humid air combustion process using liquid fuel to determine the effects of humidity on pollutant emissions and flame stability. Tests were conducted at pressures of up to 100 psia (690 kPa), and a typical inlet air temperature of 860°F (733 K). The emissions and RMS pressures were documented for a relatively wide range of flame temperature from 2440-3090°F (1610–1970 K) with and without added humidity. The results show more than 90% reduction of NOx through 10% humidity addition to the compressed air compared with the dry case at the same flame temperature. The substantial reduction of NOx is due to a shift in the chemical mechanisms and cannot be explained by flame temperature reduction due to added moisture since the comparison was made for the same flame temperature.

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.

NOx Removal Process by Injection of NH3 and H2O2 in Gas Turbine Exhaust Gas

1979 ◽  
Author(s):  
Y. Hishinuma ◽  
F. Nakajima ◽  
H. Akimoto ◽  
Y. Uchiyama ◽  
S. Azuhata ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Nox Reduction ◽  
Reduction Rate ◽  
Reduction Process ◽  
Heterogeneous Reactions ◽  
High Rate ◽  
Exhaust Gas ◽  
Reduction Of Nox ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust

For the removal of NOx in a gas turbine exhaust gas, the reduction of NOx with NH3 and H2O2 was studied. It was found that the addition of H2O2 very effectively lowers the reduction temperature of NO with NH3 and that more than 90 percent NOx reduction could be attained at 550 C in the absence of O2. However, the NOx reduction rate decreased with increases in the concentration of O2, and NOx reduction was about 40 to 60 percent under gas turbine exhaust gas condition (15 percent O2). In order to attain a high rate of reduction of NOx, a combined reduction process, which consisted of homogeneous gas phase and the catalytic heterogeneous reactions, was also developed. The efficiency of the new process was proved in a pilot plant using half a size model of a 25-MW gas turbine combustor.

Sign in / Sign up

Export Citation Format

Share Document