Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

OP-III-18METHANE STEAM REFORMING IN A MICROCHANNEL REACTORFOR GTL INTENSIFICATION: A COMPUTATIONAL FLUIDDYNAMICS SIMULATION STUDYG. Arzamendi a , P.M. Diéguez a , M. Montes b , J.A. Odriozola c ,E.F. Sousa-Aguiar d , L.M. Gandía aa Departamento de Química Aplicada. Universidad Pública de Navarra. E-31006, Pamplona,Spain, E-mail: lgandia@unavarra.esb Departamento de Química Aplicada. Facultad de Ciencias Químicas de San Sebastián.Universidad del País Vasco. E-20018, San Sebastián, Spainc Instituto de Ciencia de Materiales de Sevilla, Centro mixto CSIC-Universidad de Sevilla,41092 Sevilla, Spaind CENPES/PDEDS/Petrobrás. Av. Horácio Macedo, 950 - Ilha do Fundão CEP 21941-915Rio de Janeiro, BrazilIntroductionGas-to-Liquid (GTL) processes allow monetizing the vast natural gas reserves existing inremote areas around the world as well as fulfilling the flaring constraints imposed onassociated gas from oil fields. GTL technology is based on the conversion of natural gas tohigh quality liquid synfuels in several stages: syngas generation, production of long-chainhydrocarbons by Fischer-Tropsch (FT) synthesis, and hydrocracking of the heavy fractionsfor naphta, diesel and lubricants production [1]. Steam reforming of natural gas over nickelcatalysts is the preferred technology for syngas production. This route is highly efficient butstrongly endothermic (ΔHº 298 = 206 kJ/mol). On the other hand the FT synthesis is veryexothermic (ΔHº 298 = -165 kJ/mol). Therefore, heat transfer issues are of the greatestimportance for these processes which for this reason are capital intensive. One of theoutstanding characteristics of microreactors is heat transfer enhancement; then, microreactortechnology provides an opportunity for the intensification of the GTL processes [2].Results and DiscussionIn this work, a Computational Fluid Dynamics (CFD) study with ANSYS CFX software ofheat transfer in microchannel catalytic reactors for methane steam reforming (MSR) and FTsynthesis is presented. The simulated microreactor is a steel block 17 mm high, 21 mm width,and 21 mm long containing 80 microchannels 1 mm high, 1 mm width, and 21 mm long.Simulations have been conducted under operating conditions relevant for the intensification ofthe GTL processes. It has been assumed that a very thin layer of an active catalyst has beenuniformly deposited onto the walls of the microchannels. As concerns the MSR reaction, firstorder kinetics with respect to CH 4 according to the rate expression for Ni of Bodrov et al. [3]has been considered whereas the water gas shift reaction has been assumed to be at equilibrium.Gas hourly pace velocities (GHSV) were of the order of 27,550 h –1 with H 2 O/CH 4 molar ratio125