CFD MODELLING OF A NOVEL STIRRED REACTOR FOR THE BIO-PRODUCTION OF HYDROGEN

JAVIER A. FRANCESCONI

Mar del Plata

Congreso; 4ºCongreso Nacional - 3° Congreso Iberoamericano HIDRÓGENO Y FUENTES SUSTENTABLES DE ENERGíA; 2011

IEDS

In this work, the Computational Fluid Dynami cs (CFD) simulation of a stirred bio-reactor purposely designed for the production of H2 from organic wastes is considered. Due to its geometrical and physical complexity, the selected reactor offers a very challenging benchmark for the multiphase flow model capability and poses additional numerical and modelling issues with respect to previously investigated gas-liquid stirred tanks.  The same geometrical configuration and oper ating conditions for which fluid dynamics experimental data were available are considered  for strictly evaluating the model capability and for highlighting the possible critical issues of the simulation. In order to isolate the numerical uncertainties associated with the complexity of the computational domain, the results of preliminary single phase simulations have been comp ared with single phase velocity data collected by Particle Image Velocimetry. Afterwards, the  gas ingestion from the surface vortex in the draft tube and the gas dispersion in the whole vessel  volume has been analyzed via the numerical solution of model equations based on the Two -fluid Model. The applicability of the CFD simulation method adopted in this work for the optimization and the scale up of the bioreactor for the H2 production from food and zootechnical wastes  is discussed through a critical analysis of the results of the prediction.