OP-II-3

PP-I-60with honeycomb catalyst) acting by residual, quite small, ammonia amount only and,as a consequence, oxidation reaction heat production and catalytic corrosion arehighly small.The second step allows us to reveal the side homogeneous reaction of nitrousoxide with ammonia in honeycomb channels contribution to the nitrous oxide yield.This step based on the ideal honeycomb catalyst model. Such catalyst ischaracterized with top activity and selectivity. It means that, firstly, its activity isenough for providing of a zero ammonia concentration at a honeycomb catalystsurface (i.e. mass transfer limitation approach is just), and, secondly, that ammoniacompletely converts to nitrous oxide. Limitation of oxygen transport rate to channelwall was not taken into account in the model. Obtained data for different shapechannels are compared with each other in the paper. Comparison was made atidentical reaction mixture mass flow rate over honeycomb cell and channels densityper square inch. Inlet ammonia and nitrous oxide concentrations in the channel (i.e.in the gas mixture that leaves platinum gauzes) were varied. Gas flow was supposedas isothermal due to low inlet ammonia concentration (by the same reason that wasconsidered in the first investigation step).Models parameters used in calculations were corresponded to commercial plantsUKL-7 (P=7 atm, T=900°C) and AK-72 (P=3,5 atm, T=850°C) conditions atcorresponding values of superficial gas velocities.Calculations were carried out at ANSYS FLUENT 6.3.26 program at cluster systemNCS-160 and server SMP4x64 of Siberian Super-Computer Center of SB RAS.References[1]. Zakharov V.P., Zolotarskii I.A., Kuzmin V.A. CFD simulation of “gauze pad – honeycomb”catalytic system//Chem. Engng J. 91 (2003) 249-255.[2]. Golovnya E.V., Brustein E.A. Two-stage ammonia oxidation system with non-platinum secondstage honeycomb catalyst optimization//Catalysis in industry 3 (2004) 9-14 (in Russian).[3]. Vanchurin V.I., Golovnya E.V., Brustein E.A. Ammonia oxidation over oxide honeycombcatalyst//Catalysis in industry 5 (2006) 52-57 (in Russian).[4]. Beskov V.S., Brustein E.A., Golovnya E.V., Vanchurin V.I. Simulation of process of ammoniaoxidation over platinoid gauzes//Catalysis in industry 2 (2008) 31-36 (in Russian).[5]. Isupova L.A., Sutormina E.F., Zakharov V.P., Rudina N.A., Kulikovskaya N.A., Plyasova L.M.Cordierite-like mixed oxide monolith for ammonia oxidation process//Catalysis Today 1475 (2009)5319-5323.[6]. Heat-exchangers handbook, vol.1, M: Energoatomizdat, 1987, pp. 247-248 (in Russian).327