This week a new paper has been published in the IFRF Combustion Journal (http://www.journal.ifrf.net), entitled:

NOx EMISSION FROM HIGH TEMPERATURE AIR VERSUS METHANE/AIR COUNTER-FLOW PARTIALLY PREMIXED FLAME

by

M. HAMDI, H. BEN TICHA, and M. SASSI

Corresponding Author:

Mohamed Sassi
Laboratoire d’Etudes des Systèmes Thermiques et Energétique
Ecole Nationale d’Ingénieurs de Monastir
5019 Monastir, Tunisia.

E-mail: mohamed.sassi@enim.rnu.tn

Summary:

The High Temperature Air Combustion (HiTAC) regime, in which reactants are preheated prior to mixing and burning by recycled exhaust gases, has proven to be an attractive method for application in advanced industrial furnaces for energy saving and reduction of NOx emissions. In this technology, air diluted by nitrogen or combustion products can be preheated to high temperatures, while rich or lean methane/air mixtures can be injected into the preheated gases to realize diffusion or partially premixed combustion. The objective of the present study is to understand partially premixed lean or rich methane/air flames in counter-flow with preheated air in order to provide fundamental understanding of the physical and chemical processes that occur during this combustion mode. HiTAC is shown to improve fuel consumption, and to have the beneficial effect of low NOx emission when high temperature air with low concentration of oxygen is used. This study is based on a numerical modeling of an opposed flow diffusion flame with the Oppdif/CHEMKIN software using the detailed comprehensive (GRImech3.0) mechanism for the oxidation kinetics of methane. Two partially premixed flames (rich and lean methane/air mixture) are selected to simulate this combustion regime. Simulation results clearly illustrate that the flame structure for the rich partially premixed flame is significantly affected by the oxygen concentration in the air. For this flame, and with 5% oxygen content in the air, a significant reduction in NOx emission is observed, but this is accompanied by higher CO emissions. On the other hand, the results show that the low oxygen content in preheated air does not much affect the NOx emissions for the lean partially premixed flames.

Key words:

High Temperature Air Combustion (HiTAC), NOx emissions, counter-flow partially premixed flame, Oppdif/Chemkin

FULL PAPER:

The full paper may be downloaded from the server, in the “New Papers” section (http://www.journal.ifrf.net/articles.html), by clicking on the Acrobat PDF icon alongside the title.

Publication in the Journal

The Editor-in-Chief (See associated article in this edition of the MNM) would like to remind all potential authors that publication in the Journal is open to all. If you have interesting results to publish in the field of, or related to, industrial combustion, we invite you to prepare a paper according to the guidelines given in the Author’s Guide on the website (http://www.journal.ifrf.net/).

Papers may be regular “articles” (typically up to 20 pages) or Communications (typically up to 4/5 pages). Review papers can of course be longer. Remember that figures and graphics in general can be in full color. This advantage should be encouraged.

All manuscripts and associated files, proposed for publication should be sent by the Corresponding Author in a compressed/zip file, as an email attachment to journal@ifrf.net. This file should include a statement that the proposal’s content is unpublished material that has not being submitted for publication elsewhere. When an article by the author(s) is cited in the proposed article as “in press”, a copy of this article should accompany the proposed article and should be included in the compressed file.

The Editor-in-Chief looks forward to receiving your proposals.