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OP-I-30OXYDATIVE COUPLING OF METHANE IN THE FLUIDIZED BEDREACTOR: INFLUENCE OF HYDRODYNAMICS AND KINETICS ONTHE PRODUCT DISTRIBUTIONJašo S., Arellano-Garcia H., Wozny G.Berlin Institute of Technology, Strasse des 17. Juni 135, Sekr. KWT9 10619 Berlin,stanislavjaso@mailbox.tu-berlin.deDirect conversion of methane into other useful products is one of the mostchallenging subjects to be studied in heterogeneous catalysis. The OxidativeCoupling of Methane (OCM) process, in which methane is catalytically converted toC2 products (ethane and ethylene), is considered to be a suitable technology withhigh potential to exploit the huge amounts of natural gas as a feedstock. However,OCM is faced with two main drawbacks which are limiting its practical application.First one is the low yield of the reaction [1,2] which is limited to less than 30% so far.Other major drawback is the exothermicity of the reaction and severe hot spots [1].Fluidized bed reactor was proposed by several authors [2,3] as the mostpromising reactor concept for the OCM. It was proven that operation with undilutedfeeds of methane and oxygen is possible, with retaining nearly isothermaltemperature profile [2,3,4]. However, yields of ethane and ethylene did not improvesignificantly, and they were in most cases similar like the ones obtained in the fixedbed reactor.Scale-up and modelling of the fluidized bed reactors is presently done usingeither simple algebraic models or models based on the two phase theory. However,these models do not give insight into bed hydrodynamics, and are in all casesisothermal. Moreover, with such models it is impossible to investigate the influence ofthe distributor plate design, distributed feeding policy or effects of internals on thereactor performance.In this contribution we developed a comprehensive 3D model (Fig. 1) for thefluidized bed reactor using a commercial CFD tool Fluent 6.3, based on the Euleriangranular flow model. Implemented kinetic model is the most comprehensive formalkinetic model for the OCM available in the literature [5], containing 10 parallel-seriesreactions. Reaction network and heat transfer coefficients had to be implementedthrough external UDF subroutines.94