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Show ) in Germany to reduce all emissions greater than 500 mg/Nm3, make glass, concrete, steel producers worried and researcher working on that problem. because at the AIR LIQUIDE company we use to work with these industries, we are deeply envolved in such a research. In that paper we will present a computationnal method developed at the AIR LIQUIDE Research Center, in order to predict NOx production in any combustion chamber. After validating this approach with pilot-scale experiments, we will present some calculations for an industrial application (a glass melting furnace). Comparing pure oxygen and preheated air processes, it appears a great interest in using pure oxygen regarding the NOx emissions and the next air pollution regulations. Nevertheless after experimental investigations and computational modeling, we found out that pure oxygen combustion must be perfectly mastered to obtain a good control of the process and very low pollutant emissions. In conclusion we will then indicate the sensitive parameters of such a process, and some low NOx emissions observed using AIR LIQUIDE Burners. II Computer modeling Computer modeling methods, if theoritically well grounded and experimentally validated, provide a valuable tool for apprehending such a difficult problem. Combining two codes, ATHENA and CHEMKIN, we developed a program to simulate a flame and predict NOx emissions from glass melting furnaces. ATHENA is a fluid mecanics code developed at the AIR LIQUIDE Research center especially for oxygen enhanced and pure oxygen combustion (high level of radiative transfer). CHEMKIN is a code very well known by combustion modelers, which allows for investigating chemistry and gas phase kinetics problem in flames. 1. ATHENA (~ero THErmo ~umerical code of l'~ir liquide) ATHENA provides for a given furnace geometry and for given flame characteristics a 3D mapping of the following parameters : gas and wall temperature, gas velocity, residence time, and main species concentration as determined by mixing laws in that furnace. ATHENA deals with fluid mechanics, radiative and convective heat transfer and geometry. Fluid mechanics is based on a finite volume numerical method to solve the continuity equation and the 3D Navier-Stokes equations. Turbulence is treated by using a standart K-€ model with wall function. The chemistry is d~fined just by a single reaction (Fuel + Oxydant ---> Products ). To model the radiative transfer, a discret method is used based on the "gray gas" Hottel's method. ~ith the computational tool VISAL4D we can dessign interactively the geometry of the studied furnace, the grid size and the boundary conditions. 2. CHEMKIN CHEMKIN Fortran programs computer is a general purpose, problem independent, transportable, Chemical Kinetics code package [3]. This package of Fortran are designed to facilitate a chemist's interaction with the in modeling chemical kinetics. The modeling process requires |