In the following study, the simulation of the polymeric-grade acrylic acid (AA) production process is carried out using the simulator ChemCAD ® version 5.2.0., in order to obtain mass balance results in all the process streams and also to know the most important design parameters of the equipment used. Two sensitivity studies were carried out: 1) influence of the absorption tower operating temperature in the amount of AA obtained at the bottom column; and 2) influence of the recovery column working pressure in the amount of acetic acid obtained on it. At the recovery column a liquid bottom stream containing AA with 99.90 % purity is obtained, while in the acids column the AA is obtained with 99.86 % purity at the bottom stream. It's recommended that the absorption tower operates at a temperature near 20 °C, while the recovery column must run under vacuum conditions, in order to reduce both the AA and acetic acid losses.

En el presente trabajo se llevó a cabo el diseño de una columna empacada para efectuar la absorción de etanol contenido en una corriente gaseosa usando agua como solvente. Como material de empaque se seleccionó anillos plásticos Nor-Pac ® de 35 mm. Se obtuvo un diámetro de la columna de 0,334 m; la caída de presión total calculada fue de 321 Pa/m, la cual es inferior a la permitida por el sistema de absorción (350 Pa/m); se obtuvo un coeficiente global volumétrico de transferencia de masa de 0,201 kmol/m 3 s; la altura de empaque tuvo un valor de 1,97 m; y la altura total de la columna de absorción fue de 4 m. La columna empacada tendrá un costo total aproximado de usd 22.000.

In the present work, a packed bed absorption column is designed to recover certain amounts of ethanol contained in a gaseous stream. Four packing types (50-mm metal Hiflow® rings, 50-mm ceramic Pall® rings, 50-mm metal Top Pak® rings and 25-mm metal VSP® rings) are considered in order to select the most appropriate one in terms of column dimensions, pressure drop and mass-transfer results. Several design parameters were determined including column diameter (D), packing height (Z), overall mass-transfer coefficient (Km) and gas pressure drop (P/Z), as well as the overall number of gas-phase transfer units (NtOG), overall height of a gas-phase transfer unit (HtOG) and the effective surface area of packing (ah). The most adequate packing to use for this absorption system constitutes the 25-mm metal VSP® rings, since it provided the greatest values of Km (0.325 kmol/m3.s), and ah (169.57 m-1), as well as the lowest values of both Z (0.6 m) and HtOG (0.145 m), meaning that it will supply the higher mass-transfer conditions with the lowest column dimensions. The influence of both gas mixture (QG) and solvent (mL) feed flowrates on D, Z, Km, P/Z, NtOG and HtOG was also evaluated for the four packing considered. The design methodology was solved using computing software MATLAB® version 7.8.0.347 (R2009a) (Math Works, 2009), and also Microsoft Excel®.D

Background: Process simulation has been extensively used in recent years to design, evaluate or optimize processes, systems and specific operations of the chemical industry and its related disciplines. Currently, CHEMCAD® constitute one of the most used process simulators because of the great number of chemical and petrochemical processes that can be simulated.Method: The simulation of the production process of styrene via catalytic dehydrogenation of ethyl-benzene is carried out by using the process simulator CHEMCAD® version 5.2.0, in order to determine the composition and mass flow-rate of each process involved in the production, as well as the main operating parameters of the equipment used. Two sensitivity studies were carried out: firstly, the influence of the temperature and pressure values applied at the LLV Separator on the amounts of ethyl-benzene and styrene to be obtained by the intermediate and top currents of this equipment; secondly, the influence of the operating pressure of the Distillation Column No. 1 (benzene-toluene column) on the quantity of ethyl-benzene and styrene obtained at the bottom stream. The simulating software MATLAB® version 7.8.0 was used to process the results obtained.Results: Around 9234.436 kg/h of styrene is obtained in the last distillation column with 99.6% purity. Additionally, it was found that the water is the main impurity found on this stream, which represents 0.35% of the weight.Conclusions: The LLV Separator must operate at a low temperature (5 – 10 ºC) and at a relatively high pressure (10 bar), whereas the Distillation Column No. 1 must work at a pressure near atmospheric (1.0 bar), or preferably under vacuum conditions in order to obtain the highest yields of styrene and ethyl-benzene.

Los biofertilizantes se han convertido en una alternativa de bajo costo, efectiva y amigable con el medio ambiente en comparación con los fertilizantes químicos. En el presente trabajo se desarrollaron los modelos de ingeniería de proceso y costo de una planta de biofertilizantes líquidos con una capacidad de 44 toneladas por año (568 kg/lote). Los modelos fueron obtenidos empleando el simulador de procesos SuperPro Designer® versión 8.5 (Intelligen, 2012), mientras que el diseño conceptual en 3D y dimensionamiento de la planta se desarrolló mediante el software OptiPlant (ASD Global, 2015). Se requiere una inversión total de USD $ 3 975 000 para erigir la planta, el costo de producción unitario de una botella de 1,5 L de biofertilizantes líquido es de USD $ 24,009, mientras que los indicadores económicos Valor Actual Neto (VAN) y Tasa Interna de Retorno (TIR) tuvieron valores de USD $ 716 000 y 2,55 %, respectivamente. También se obtienen ganancias totales de USD $ 985 000/año y un valor del Período de Retorno de la Inversión de 6,70 años.