Numerical Simulation of O3 and NO Reacting in a Tubular Flow Reactor

Abstract A process capable of NOx control by ozone injection gained wide attention as a possible alternative to proven post combustion technologies such as selective catalytic (and non-catalytic) reduction. The purpose of the work was to develop a numerical model of NO oxidation with O3 that would be capable of providing guidelines for process optimisation during different design stages. A Computational Fluid Dynamics code was used to simulate turbulent reacting flow. In order to reduce computation expense a 11-step global NO - O3 reaction mechanism was implemented into the code. Model performance was verified by the experiment in a tubular flow reactor for two injection nozzle configurations and for two O3/NO ratios of molar fluxe. The objective of this work was to estimate the applicability of a simplified homogeneous reaction mechanism in reactive turbulent flow simulation. Quantitative conformity was not completely satisfying for all examined cases, but the final effect of NO oxidation was predicted correctly at the reactor outlet.

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Experimental and kinetic modeling study for N2O formation of NH3-SCR over commercial Cu-zeolite catalyst

Advances in Mechanical Engineering ◽

10.1177/16878140211010648 ◽

2021 ◽

Vol 13 (4) ◽

pp. 168781402110106

Author(s):

Songfeng Li ◽

Chunhua Zhang ◽

Ao Zhou ◽

Yangyang Li ◽

Peng Yin ◽

...

Keyword(s):

Kinetic Model ◽

Flow Reactor ◽

Catalytic Reduction ◽

Current Model ◽

Ammonia Nitrogen ◽

No Oxidation ◽

Reactor Outlet ◽

N2o Formation ◽

Scr System ◽

Denox Efficiency

In this paper, a systematic experimental and kinetic model investigation was conducted over Cu-SSZ-13 catalyst to study the DeNOx efficiency and N2O formation for selective catalytic reduction of NOx with NH3 (NH3-SCR). The kinetic model was developed for various reactions to take place in the NH3-SCR system, including NH3 adsorption/desorption, NH3 oxidation, NO oxidation, standard SCR, fast SCR, slow SCR and N2O formation reactions. In addition, the reaction of N2O formation from NH3 non-selective oxidation was taken into account. All the experiments were performed in a flow reactor with a feed stream near to the real application of diesel engine vehicles exhaust. The current model can satisfactorily predict the steady state conversion rate of various species at the reactor outlet and the effect of gas hourly space velocities and ammonia nitrogen ratio on N2O formation. The results show that the kinetic model can simulate the reaction process of the Cu-SSZ-13 catalyst well. This is significant for the optimization of NH3-SCR system for achieving the higher DeNOx efficiency and the lower N2O emission.

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Heat and mass transfer in heterogeneous catalysis. XXX. Effect of heat and mass transfer at the external surface of the catalyst particle on behaviour of an isothermal tubular flow reactor

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19712454 ◽

1971 ◽

Vol 36 (7) ◽

pp. 2454-2466

Author(s):

J. Horák ◽

F. Jiráček

Keyword(s):

Mass Transfer ◽

Heterogeneous Catalysis ◽

Heat And Mass Transfer ◽

Flow Reactor ◽

External Surface ◽

Catalyst Particle ◽

Tubular Flow Reactor ◽

Tubular Flow

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Heat and mass transfer in heterogeneous catalysis. XXXII. Experimental study of dynamic behaviour of the catalytic tubular flow reactor

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19730185 ◽

1973 ◽

Vol 38 (1) ◽

pp. 185-193 ◽

Cited By ~ 2

Author(s):

F. Jiráček ◽

J. Horák ◽

M. Hájková

Keyword(s):

Mass Transfer ◽

Experimental Study ◽

Heterogeneous Catalysis ◽

Heat And Mass Transfer ◽

Dynamic Behaviour ◽

Flow Reactor ◽

Tubular Flow Reactor ◽

Tubular Flow

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Turbulent Mixing in a Tubular Flow Reactor

Chemical engineering ◽

10.1252/kakoronbunshu1953.34.1315 ◽

1970 ◽

Vol 34 (12) ◽

pp. 1315-1323,a1 ◽

Cited By ~ 1

Author(s):

Yoshio Miyairi ◽

Mitsuo Kamiwano ◽

Kazuo Yamamoto

Keyword(s):

Turbulent Mixing ◽

Flow Reactor ◽

Tubular Flow Reactor ◽

Tubular Flow

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New Insights into the Kinetics of the Gas-Phase Oxidation of Hexafluoropropene

Progress in Reaction Kinetics and Mechanism ◽

10.3184/174751916x14764433065222 ◽

2016 ◽

Vol 41 (4) ◽

pp. 418-427 ◽

Cited By ~ 1

Author(s):

David Lokhat ◽

Maciej Starzak ◽

Deresh Ramjugernath

Keyword(s):

Gas Phase ◽

Oxidation Process ◽

Flow Reactor ◽

Packed Column ◽

Phase Reaction ◽

Analytical Technique ◽

Tubular Flow Reactor ◽

Gas Phase Oxidation ◽

Tubular Flow ◽

Kinetics Of

The gas-phase reaction of hexafluoropropene and molecular oxygen was investigated in a tubular flow reactor at 450 kPa and within a temperature range of 463–493 K using HFP/O2 mixtures containing 20–67% HFP on a molar basis. Capillary and packed column chromatography served as the main analytical technique. The reaction yielded HFPO, COF2, CF3COF, C2F4 and c-C3F6 as gas-phase products. High molecular weight oligomers were also formed. The oligomers were found to have a polyoxadifluoromethylene structure according to elemental and 19F NMR analysis. At 493 K HFP is proposed to undergo oxygen-mediated decomposition to difluorocarbene radicals, yielding greater quantities of difluorocarbene recombination products. Kinetic parameters for a revised model of the oxidation process were identified through least squares analysis of the experimental data.

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Micromixing in a tubular flow reactor under simulated microgravity

AIChE Journal ◽

10.1002/aic.690390916 ◽

1993 ◽

Vol 39 (9) ◽

pp. 1569-1573 ◽

Cited By ~ 2

Author(s):

K. S. Wenger ◽

E. H. Dunlop ◽

T. Kedar ◽

B. G. Thompson

Keyword(s):

Simulated Microgravity ◽

Flow Reactor ◽

Tubular Flow Reactor ◽

Tubular Flow

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Reactor scale-up in AOPs: from laboratory to commercial scale

Water Science & Technology ◽

10.2166/wst.2004.0207 ◽

2004 ◽

Vol 49 (4) ◽

pp. 13-18 ◽

Cited By ~ 7

Author(s):

C.S. Zalazar ◽

M.D. Labas ◽

C.A. Martín ◽

R.J. Brandi ◽

A.E. Cassano

Keyword(s):

Formic Acid ◽

Large Scale ◽

Flow Reactor ◽

Acid Output ◽

Water Solution ◽

Batch Reactor ◽

Scale Up ◽

Mass Balances ◽

Tubular Flow Reactor ◽

Tubular Flow

A procedure to scale-up photoreactors employed in AOPs using laboratory information has been developed. Operating with a model compound the proposed procedure was applied to the decomposition of formic acid in water solution using hydrogen peroxide and UV radiation. With laboratory experiments the parameters of the kinetic equation were obtained in a small batch reactor operated within a recycling apparatus. The whole system was modeled employing radiation and mass balances. These balances were used together with a non-linear parameter estimator to derive the model kinetic constants. Then, these results were used in the modeling of the large-scale reactor to predict exit conversions in an isothermal, continuous, tubular flow reactor that is 2 m long and has a volume of 12 l. Once more, radiation and mass balances were used to predict formic acid output concentrations. Experimental data in the large-scale apparatus are in good agreement with theoretical predictions.

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