Simulación y control

 

Modeling the configuration characteristics and operating regimes of a binary distillation column for control

 

Modelado de las características de configuración y regímenes de operación de una columna de destilación binaria para su control

 

D. Juárez–Romero¹*, F.R. López–Estrada³, C.M. Astorga–Zaragoza², V. Alvarado², J.A. Hernández¹ and A.C. Tellez–Anguiano²

 

¹ Centro de Investigación en Ingeniería y Ciencias Aplicadas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Col Chamilpa, Cuernavaca, Morelos, México, C.P. 622209. *Corresponding author. E–mail: djuarezr7@gmail.com

² Centro Nacional de Investigación y Desarrollo Tecnológico, Interior Internado Palmira s/n, Col. Palmira. Cuernavaca, Morelos, Cuernavaca, Morelos, México. C.P. 62490.

³Instituto Tecnológico de Tuxtla Gutiérrez, Departamento de Ingeniería Eléctrica y Electrónica Carretera panamericana Km 1080 S/N, CP 29000, Tuxtla, Gutiérrez, Chiapas, Mexico.

 

Recieved 29 of November 2009.
Accepted 12 of October 2010.

 

Abstract

This work describes a mathematical model for a distillation column which includes mass, composition, and energy balances, where the thermodynamic and equilibrium properties are represented by an equation of state. This model focuses on the specific configuralion of the boiler (container plus boiling vessel, and the vertical condenser (with an external (cooling jacket plus a helical pipe) and also on the effect of atmospheric and subcooling conditions in the condenser. For the sake of flexibility and to represent consistently the semi–continuous conditions during the startup, the equations are solved as a DAEs set. Results are compared with experimental data from a Methanol–Ethanol mixture in a 10–tray distillation column. The effects of configuration and operating conditions on the model fidelity are discussed. The model describes the semi–continuous hydraulics and the desired temperature profile that is expected to be used for process control.

Keywords: distillation column dynamics, condensate subcooling, model fidelity, distillation column configuration.

 

Resumen

Este trabajo describe un modelo matemático para, una columna de destilación que incluye los balances de masa, composición, y energía, donde las propiedades termodinámicas y de equilibrio están representadas por una ecuación de estado. Este modelo se enfoca a la descripción específica del rehervidor (que tiene un contenedor más un tanque de ebullición) y el condensador vertical (con una chaqueta de enfriamiento externa, más un tubo helicoidal) y también los efectos de las condiciones atmosféricas y de sub–enfriamiento en el condensador. A fin de tener flexibilidad y para representar consistentemente las condiciones semi–continuas durante el arranque, las ecuaciones son resueltas como un conjunto de EAD. Los resultados son comparados con datos experimentales para una mezcla metanol–etanol en una destilación de 10–platos. Se discuten los efectos de la configuración y las condiciones de operación en la fidelidad del modelo. El modelo describe la hidráulica semi–continua y el perfil de temperaturas que se espera sea utilizado para control de procesos.

Palabras clave: dinámica de columnas de destilación, subenfriamiento de condensado, fidelidad de modelo, configuración de columna de destilación.

 

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Appendix A.

Appendix B.