scholarly journals Combined Removal Of NOx And SO2 From Flue Gas At Low Temperature

2018 ◽  
Vol 53 ◽  
pp. 04038 ◽  
Author(s):  
Zhipeng Xue ◽  
Hao Chen ◽  
Minmin Zhao
Keyword(s):  
Removal Efficiency ◽  
Flue Gas ◽  
Gas Flow ◽  
Ph Value ◽  
National Standards ◽  
Raw Material ◽  
Nox Removal ◽  
Gas Temperature ◽  
Solution Ph ◽  
Nox Removal Efficiency

A method was proposed to remove NOx and SO2 in flue gas by using the sulfinyl functional group as a catalyst. Ozone is introduced into the flue gas to oxidize NO. Soluble NO2 and SO2 reacted with ammonia to form ammonium sulfate and ammonium nitrate, which were the raw material of the compound fertilizer. A small pilot is built in a container that can be easily transported to power plant and extracts the actual flue gas directly from the gas duct. In order to obtain the best the SO2 and NOX removal efficiency in this experiment, many parameters were changed. Such as flue gas flow, ozone / NOX ratio, liquid-gas ratio, flue gas temperature, catalyst type, catalyst concentration, solution pH value. Results indicated that SO2 was cleaned up quite efficiently and the removal efficiency was nearly 99% under all conditions. the best NOX removal efficiency can reach 88%. The NOX removal efficiency depended primarily on ozone / NOX ratio, and the temperature of flue gas also had influence on the NOX removal efficiency. The optimum pH range is 5.6-6.3. After inspection by authoritative institutions, the quality of fertilizers is superior to national standards.

Study on the Experiments of Flue Gas Denitrification and Desulfurization Using Nitric Acid Solution

2008 ◽  
Author(s):  
Bao-Ming Sun ◽  
Shui-E Yin ◽  
Zhong-Li Wang
Keyword(s):  
Nitric Acid ◽  
Oxygen Concentration ◽  
Removal Efficiency ◽  
Flue Gas ◽  
Nitric Acid Concentration ◽  
Nox Removal ◽  
No Removal ◽  
Nox Removal Efficiency ◽  
The Individual ◽  
So2 Concentration

The present study attempts to take nitric acid as absorbent to clean up SO2 and NO gases simultaneously from the simulated flue gas in the lab-scale bubbling reactor, this study was divide into the individual DeNOx experiments and the combined DeSOx/DeNOx experiments: the individual DeNOx experiments were carried out to examine the effect of various operating parameters such as input NO concentration, nitric acid concentration, oxygen concentration input SO2 concentration, adding KMnO4 as additive and taking NaOH as the secondary absorption processes on the SO2 and NOx removal efficiencies at room temperature, the results of the individual DeNOx show that NO removal efficiency of 70%–95% were achieved under optimized conditions. NO removal efficiency increased with the increasing nitric acid concentration and increased by adding KMnO4 into the absorbent as additive as well. The removal efficiency of NO can reach 95% when using the two-step integrated processes of (HNO3+KMnO4)-NaOH, the absorption solution of 50% nitric acid, 400ppm of input NO concentration. 0.5% oxygen concentration and without SO2 in the simulated flue gas. No improvement on the NOx removal efficiency was observed with the increasing of KMnO4 and NaOH concentration in the scrubbing solution. The results of the combined DeSOx/DeNOx experiments show that the maximum DeNOx and DeSOx efficiencies ranged from 36.6% to 81% and from 99.4% to 100.0%, respectively. The prime parameters affecting the NOx removal efficiency are the oxygen concentration and the input SO2 concentration.

Evaluation of NOX Removal from Simulated Flue Gas by "Absorption-Oxidation-Reduction" Method

2014 ◽  
Vol 884-885 ◽  
pp. 261-265
Author(s):  
Bao Lin Li ◽  
Ming Yu Li ◽  
Hai Hao Liu ◽  
Gang Cao ◽  
Gang Ren ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Flow Rate ◽  
Flue Gas ◽  
Ferrous Sulfate ◽  
Gas Flow ◽  
Reduction Method ◽  
Ph Value ◽  
Sulfate Solution ◽  
Gas Flow Rate ◽  
Oxidation Reduction

This paper presented a new method of absorption-oxidation-reduction which used ferrous sulfate solution as absorbent, oxygen as oxidizer and urea as reducer to remove NOX from flue gas based on the properties of Fe2+, NO, [Fe (NO)]2+ and urea. These properties included that Fe2+ and NO could produce [Fe (NO)]2+, furthermore [Fe (NO)]2+ was easy to be oxidized by O2, as well as urea can reduce HNO2 and HNO3 in the absorption liquid. This research was to discuss its absorption and removal mechanism with the influence of the initial urea concentration, pH value, initial NOX concentration and gas flow rate on the NOX removal efficiency. The results showed that the removal efficiency of NOX would increase when the initial concentration of urea and NOX increased, while the pH value and gas flow rate decreased.

Experiment on Simultaneous Absorption of NO and SO2 from Sintering Flue Gas by Oxidizing Agents of KMnO4/NaClO

2014 ◽  
Vol 12 (1) ◽  
pp. 539-547 ◽  
Author(s):  
Ying Li ◽  
Wenqi Zhong ◽  
Jing Ju ◽  
Tiancai Wang ◽  
Fei Liu
Keyword(s):  
Removal Efficiency ◽  
Flue Gas ◽  
Initial Solution ◽  
Molar Ratio ◽  
Gas Temperature ◽  
Inlet Concentration ◽  
Solution Ph ◽  
Experimental Conditions ◽  
Simultaneous Absorption ◽  
Spray Absorption

Abstract A complex oxidizing agent combination made up of KMnO4 and NaClO was used to investigate the simultaneous absorption of NO and SO2 from sintering flue gas in a spray absorption tower on a laboratory scale. The effects of various operating parameters, i.e. initial gas temperature (Tg), initial solution pH, molar ratio of NaClO/KMnO4 (M), initial NO inlet concentration (CN) and SO2 initial inlet concentration (CS), were systematically investigated in the experiments. The results showed that the removal efficiency of SO2 was slightly affected by the reaction conditions and remained stable above 98%; however, the removal efficiency of NO was significantly influenced. It presented different trends with the reaction condition changed. The most optimal experimental conditions for simultaneous removal of NO and SO2 were found to be initial solution pH=5.5, Tg=50°C, M=3; in this case the average removal efficiencies of NO and SO2 could reach 98.8 and 70.9%, respectively.

Influence of gas flow patterns on NOx removal efficiency

1998 ◽  
Vol 52 (1-6) ◽  
pp. 339-343 ◽  
Author(s):  
A.G. Chmielewski ◽  
B. Tymiñski ◽  
A. Dobrowolski ◽  
S. Sato ◽  
O. Tokunaga ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Gas Flow ◽  
Flow Patterns ◽  
Nox Removal ◽  
Nox Removal Efficiency

scholarly journals Effect of Absorbents on NOx Removal through Polyvinylidene Fluoride (PVDF) Hollow Fiber Membrane Modules

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Irfan Purnawan ◽  
Sutrasno Kartohardjono ◽  
Levana Wibowo ◽  
Annisa Faiza Ramadhani ◽  
Woei Jye Lau ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Removal Efficiency ◽  
Polyvinylidene Fluoride ◽  
Gas Flow ◽  
Hollow Fiber Membrane ◽  
Sodium Chlorate ◽  
Sodium Chlorite ◽  
Nox Removal ◽  
Wet Process ◽  
Nox Removal Efficiency

NOx (NO and NO2) are air toxins that endanger life and represent a hazard to the environment, such as photochemical smog, global warming, acid rain, ozone depletion, and the occurrence of respiratory infections. Some technological strategies to diminish NOx emissions to meet regulations depend on two techniques: the dry process and the wet process. This study applies polyvinylidene fluoride (PVDF) hollow fiber membrane modules as a medium to remove NOx from solutions containing several absorbents such as hydrogen peroxide and nitric acid (H2O2-HNO3) solutions, sodium chlorite and sodium hydroxide (NaClO2-NaOH) solutions, and sodium chlorate and sodium hydroxide (NaClO3-NaOH) solutions. The experimental results showed that the oxidant’s strength influences NOx removal efficiency, where the absorbent solutions containing hydrogen peroxide had the highest removal efficiency as hydrogen peroxide is the most potent oxidant, followed by sodium chlorite and sodium chlorate. The three pairs of absorbents also gave a high NOx removal efficiency (above 90%), which means that all the absorbents used in the study are very potential to be used to diminish NOx via the wet process. NOx removal efficiency at the same feed gas flow rate increased as the number of fiber and absorbent concentrations is increased. However, NOx removal efficiency is reduced as the feed gas flow rate is increased at the same membrane module and absorbent concentration.

Industrial Demonstration on NOx Removal by Gas Reburning in a 50MWE Tangential Pulverizing Coal-Fired Boiler

2006 ◽  
Author(s):  
Xiaofeng Lu ◽  
Hanzhou Liu ◽  
R. S. Amano
Keyword(s):  
Removal Efficiency ◽  
Gas Flow ◽  
Low Rank ◽  
Nox Removal ◽  
Ball Mills ◽  
Burn Out ◽  
Nox Removal Efficiency ◽  
Removal Technologies ◽  
Available Technology ◽  
Industrial Demonstration

More than 70% of NOx in air comes from various coal burning processes. Among NOx removal technologies, gas-reburning technology have been proven to be an available technology by all industrial demonstrations in USA and Europe. To identify the feasibility of NOx removal with gas reburning technology for low rank coal in China, an industrial demonstration test of NOx removal with the gas reburning technology was carried in a 220t/h tangential pulverizing coal-fired boiler in JiangYou power plant from 2002 to 2004. In the test, reburning gas and burn out air were arranged at the front and rear walls of the furnace in a creative way. It was the first time in the world for such an arrangement method of reburning gas and burn out air were applied. The relationship of NOx removal efficiency with the nature gas flow rate, the Oxygen content in the furnace and operating methods of ball mills (or the Third Air) were tested. During the test, the change of the temperature of superheat steam and the furnace temperature were measured. The industrial demonstration test results showed: the NOx removal efficiency may reach at 50% and NOx discharge content may be as lower as 200 mg/nm3 when the heat value of burning coal was about 18MJ/kg (LHV). Some factors, which affected the efficiency of NOx removal, were discussed in this paper.

scholarly journals Electrochemical oxidation of sulfamethoxazole using Ti/SnO2-Sb/Co-PbO2 electrode through ANN-PSO

2019 ◽  
Vol 84 (7) ◽  
pp. 713-727 ◽  
Author(s):  
Jiteng Wan ◽  
Chunji Jin ◽  
Banghai Liu ◽  
Zonglian She ◽  
Mengchun Gao ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Electrochemical Oxidation ◽  
Removal Efficiency ◽  
Current Density ◽  
Ph Value ◽  
Ann Model ◽  
Solution Ph ◽  
Pbo2 Electrode ◽  
Artificial Neural Network Ann ◽  
Major Factors

Even in a trace amounts, the presence of antibiotics in aqueous solution is getting more and more attention. Accordingly, appropriate technologies are needed to efficiently remove these compounds from aqueous environments. In this study, we have examined the electrochemical oxidation (EO) of sulfamethoxazole (SMX) on a Co modified PbO2 electrode. The process of EO of SMX in aqueous solution followed the pseudo-first-order kinetics, and the removal efficiency of SMX reached the maximum value of 95.1 % within 60 min. The effects of major factors on SMX oxidation kinetics were studied in detail by single-factor experiments, namely current density (1?20 mA cm-2), solution pH value (2?10), initial concentration of SMX (10?500 mg L-1) and concentration of electrolytes (0.05?0.4 mol L-1). An artificial neural network (ANN) model was used to simulate this EO process. Based on the obtained model, particle swarm optimization (PSO) was used to optimize the operating parameters. The maximum removal efficiency of SMX was obtained at the optimized conditions (e.g., current density of 12.37 mA cm-2, initial pH value of 4.78, initial SMX concentration of 74.45 mg L-1, electrolyte concentration of 0.24 mol L-1 and electrolysis time of 51.49 min). The validation results indicated that this method can ideally be used to optimize the related parameters and predict the anticipated results with acceptable accuracy.

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