Luis G. Zárate

Convective heat transfer around vertical jet fires: An experimental study

The convection heat transfer phenomenon in vertical jet fires was experimentally analyzed. In these experiments, turbulent propane flames were generated in subsonic as well as sonic regimes. The experimental data demonstrated that the rate of convection heat transfer increases by increasing the length of the flame. Assuming the solid flame model, the convection heat transfer coefficient was calculated. Two equations in terms of adimensional numbers were developed. It was found out that the Nusselt number attains greater values for higher values of the Rayleigh and Reynolds numbers. On the other hand, the Froude number was analyzed only for the subsonic flames where the Nusselt number grows by this number and the diameter of the orifice.

Degradation of 4-Chlorophenol in a Batch Electrochemical Reactor Using BDD Electrodes

1 Universidad del Mar, Campus Puerto Ángel, Ciudad Universitaria S/N, Puerto Ángel, Oaxaca, México, C. P.70902 2 Universidad Popular Autónoma del Estado de Puebla, Puebla, México, C.P. 72410 3 Universidad Autónoma del Estado de México, Facultad de Ciencias, Campus el Cerrillo, Carretera Toluca Ixtlahuaca Kilómetro 15.5, Edo. de México, C.P. 50200 4 Centro Conjunto de Investigación en Química Sustentable CCIQS, UAEM-UNAM, Facultad de Química, Universidad Autónoma del Estado de México, UAEMex Carretera Toluca-Atlacomulco, km 14.5, C.P. 50200 Toluca, Mexico. * E-mail: pere@angel.umar.mx, alejandro.regalado33@gmail.com

Modeling and Hydraulic Characterization of a Filter-Press-Type Electrochemical Reactor by Using Residence Time Distribution Analysis and Hydraulic Indices

Abstract Modeling and hydraulic characterization of a filter-press-type electrochemical reactor was studied by means of residence time distribution and hydraulic indices. For these purposes, a theoretical and approximation of residence time distribution experimental curves with axial dispersion model and Danckwerts’ boundary conditions, the Morrill dispersion index, the short-circuiting index, the Morrill volumetric efficiency index, and useful volume percent were used in order to establish deviation from plug-flow ideal, as well as dead volume, and the hydraulic efficiency. The hydraulic efficiency measure of the filter-press-type electrochemical reactor confirms uniformity of flow and a highly effective useful volume percent (91u2006%-98u2006% for all liquid flow rates tested). The axial dispersion coefficients computed (0.0005–0.0021 m2/s) indicates a small deviation of plug-flow ideal. Hence, the plug-flow reactor model is reliable for purpose modeling of the filter-press-type electrochemical reactor used in this research. Furthermore, hydrodynamic characterization of the tested filter-press-type electrochemical reactor by using hydraulic indices demonstrated its suitability for several electrochemical applications.

Biodiesel Production from Jatropha oaxacana Oil by Reactive Vacuum Distillation: Optimization by Response Surface Methodology

The application of Response Surface Methodology (RSM) and Central Composite Rotatable Design (CCRD) for modeling and optimization of the influence of three operating variables (mass of catalyst, MeOH/Oil molar ratio, and temperature) on performance of Reactive Vacuum Distillation (RVD) to increase biodiesel yield is discussed in this work. Changes in RVD performance during biodiesel production were evaluated by using RSM and CCRD. A mathematical equation to model biodiesel production by RVD was derived from computer simulation programming by applying a least squares method using MATLAB® v. R2016a. Predicted values were found to be in good agreement with experimental values (with R2 = 0.934). Optimal conditions for the production of ethyl esters were: Temperature: 31.2 °C, MeOH/Oil molar ratio: 5.65:1, and mass of catalyst: 0.1344 g.

CFD Analysis of BED Textural Characteristics on TBR Behavior: Hydrodynamics and Scaling-up

Abstract In recent years, CFD has played an important role in the understanding and design of TBR’s. In this work, through CFD with Eulerian approach, a three-phase heterogeneous reactor model was developed, were the accuracy of Interfacial Momentum Exchange Model (IMEM) for the gas-solid interaction, the effect of a more detailed catalytic bed geometry description, and the pellet shape over TBR hydrodynamics of two fluid phases interacting with the solid phase was studied. Then, a second model was developed, where the validated hydrodynamic model was coupled with mass transport for an HDS process of light gasoil. Additionally, in order to insight into the scaling up process of a TBRs, the proposed columns behaviors were compared against literature columns using four different ways, and it was found that the best predictions were obtained when the models’ holdup were equaled to those evaluated in literature columns. Since in reliable literature deviations in pressure drop predictions of around 30% can be found, the model results show significant improvement against literature, achieving 5 times better accuracy in predicting pressure drops, and 50% improvement in holdup prediction; the coupled model reproduces the same conversion values compared with literature data, and predicts conversions with 95% accuracy