Heat Transfer in Trickle Bed Column with Constant and Modulated Feed Temperature: Experiments and Modeling

N. HABTU; M. ALEJANDRA AYUDE; PATRICIA M. HAURE; J. FONT; A. FORTUNY; C. BENGOA; A. FABREGAT; F. STUBER

Braga

Conferencia; GLS10 Gas Liquid and Gas Liquid Solid Reactor Engineering Congress; 2011

Heat transfer was investigated in an insulated packed bed column with co-current downflow of gas and liquid under constant and periodically modulated gas–liquid fee d temperature. Bed temperatures at three axial positions were assessed at steady state for different insulating systems , different gas and liquid flow rate s and system pressure. The experimental profiles re corded were modeled with a dynamic pseudo- homogeneous one parameter mode l to analyze the effect of operating conditions and to deduce coefficients of overall ( U) and bed to wall ( hW) heat transfer . It appears that the heat transfer is strongly affected by the system pressure, whereas the liquid flow rate has a smaller influence. The experimental data of hW were correlated with the opera ting conditions leading to a small average error of 7% in the correlation. Condensation of water vapor occurring in the column seems to contribute to the heat transfer inside the packed bed. Several dynamic experiments modulating the feed temperature were also conduct ed and de scribed with the help of the dynamic model. Predictions with the fitted values of U were in good agreement with experiments and give confidence to apply this mode l in the investigation of the catalytic wet air oxidation of phenol over carbon conducted in a trickle bed reactor under temperature feed modulation