Application of Laplace Transform for a Gas-Liquid-Solid Trickle Bed Reactor by Using the Tracer Technique

Jornandes Dias Silva

Environmental and Energetic Technology Laboratory, Polytechnic School (UPE), Recife, Brazil.

DOI: 10.4236/am.2013.41A027                

Abstract

Experimental evaluation and dynamic modelling were presented for a liquid flow (H₂O + NaOH tracer) on solid particles in a trickle bed reactor. One-dimensional dynamic mathematical model has been described to study the gas-liquid-solid process in which the liquid phase with the NaOH tracer is treated as a continuum. The physical model has been analyzed, including the formulation of initial and boundary conditions and the description of the solution methodology. An experimental setup to measure the concentrations of the NaOH tracer has been performed. The concentration measurements of this NaOH tracer have been performed in a fixed be reactor on trickling flow of the liquid phase for a range of operating conditions. The axial dispersion (D_ax) of the liquid phase, liquid-solid mass transfer (k_LS) coefficient and partial wetting efficiency (f_e) were chosen as the hydrodynamic parameters of the proposed mathematical model. Such parameters have been optimized with experimental measurents of the NaOH tracer at the exit of the trickle-bed reactor. The optimized parameters (D_ax, k_LS, and f_e) were calculated simultaneously by using the theoretical model with minimization of the objective function. Results of the proposed mathematical model have been presented and compared as of the two experimental cases. These hydrodynamic parameters were fitted by means of the empirical correlations.

Keywords

Trickle Bed Reactor; Experimental Setup; Mathematical Model; Laplace Transform; Dynamic;

Conflicts of Interest

The authors declare no conflicts of interest.

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