Laura Plazas Tovar

Reliability–Based Optimization using Surface Response Methodology to Split Heavy Petroleum Fractions by Centrifugal Molecular Distillation Process

The present work aimed to develop an experimental and computational study for optimizing the centrifugal molecular distillation process to split heavy petroleum fractions. On the basis of the balance equations and Langmuir–Knudsen equation, a mathematical model was proposed. The influence of the evaporator temperature (EVT), the feed flow rate (Q) and the interactions between them, on the overall distillate mass flow rate (D) and the distillate yield (%D) was analyzed. A full 22 factorial central plus star rotatable (α = ±√2) composite design was performed in the experimental range from 423.15 to 603.15 K for EVT and from 1.473 to 4.418 kg · h−1 for Q. The optimized conditions, using response surface methodology, established that the EVT must range from 540 to 600 K and the Q from 1.5 to 3.5 kg · h−1. The comparison of the experiment results with the predicted model results shows an acceptable qualitative agreement between the experiment and simulated data.

Pilot-plant Simulation, Experimental Campaign and Rigorous Modeling of a Batch MMA Polymerization Reactor for the Fabrication of Bone Tissue

Abstract As a first crucial stage for production of PMMA scaffolds, this work provides the kinetic and dynamic characterization of the MMA/Ethyl Acetate/AIBN polymerization process. Kinetic parameters are estimated by means of experimental campaigns performed on a dedicated pilot plant (batch reactor). A novel, rigorous mathematical model is developed and implemented in Fortran 90 so as to consider the peculiar characteristics and the new structure of the pilot plant and the batch reactor: actually, the new plant configuration is designed to produce the appropriated PMMA scaffolds for medical application (with very stringent specifications for low toxicity and high biocompatibility). The good agreement between model previsions and experimental results validates the kinetic parameters and the dynamic modeling.

High-boiling-point petroleum fractions upgrading using the centrifugal reactive-molecular distillation process over catalyst: Mathematical modeling and simulation including experimental validation

Abstract The modeling of the reactive molecular distillation process (centrifugal type), in which the molecular distillation process and reactive process occur simultaneously to upgrade heavy petroleum crude oil, is presented in this work. The mathematical model involves equations for the evaluation of the physicochemical properties, in – situ cracking reaction, heat, continuity and material balances. A case study is illustrated for an atmospheric petroleum residue (>673.15 K) of “W” crude oil. The influence of adding a catalyst (3 and 5 wt%) was examined under different operating conditions: the process temperature range was from 473.15 K to 523.15 K (considering a pressure between 40 – 50 Pa) and the constant feed flow rate was 1.473 kg h -1 . The results showed that the concentration of the pseudocomponent “a” shrank in both the s – and r – directions reaching an extent conversion of the feedstock about 50% with 3 and 5 wt% of catalyst. Due to the rapid temperature rise in the thin liquid film, the thickness of the film rapidly decreased in this region, whereas the amount of distillate from the split molecules continuously increased throughout the evaporator under the selected conditions. The experimental results agreed well with those obtained from the theoretical simulations, indicating the accuracy and reliability of the mathematical model, since the average percent error was no larger than 6.82%, 9.39% and 14.92% for the distillate flow rate and the extent of conversion in the distillate and in the residue stream, respectively.