Processo de microfiltração de efluente da indústria têxtil utilizando membrana de fibra oca - modelagem e simulação.

Abstract

The textile industries are, in general, major water consumers, mainly due to their garment dyeing processes, consequently, the textile industries are presented as great effluent generators. These effluents are associated with a great quantity of chemical products, within these products, the dyes stand out, which confer to the water an undesirable color, besides contributing to the increase of BOD and COD of the effluent. The indigo dye is a commonly used dye in the textile industry, mainly for the coloring of jeans and denim garments. From the water treatment processes used to separate indigo from water, the membrane separation processes can be highlighted, these comprise physical separation process’ based on the use of a semipermeable barrier to separate the components. One of the major problems in the membrane separation processes is the formation of a concentration polarization layer. This work had the aim to study the indigo-water separation process using membranes. For so, a grid convergence study was realized, in addition to defining a fluid dynamical model based on a multicomponent mixture approach to study the mass transfer phenomena. Also, the resistance-in-series model was used to simulate the formation of the concentration polarization layer. The grids were generated using the software ICEM CFD 15.0, while the simulations were done using the computational package Ansys CFX 15.0, also, a VBA code was developed do determine the thickness of the concentration boundary layer. Results showed that, based on the Grid Convergence Index, a grid with 87759 elements was chosen to follow through with the study. While the fluid dynamics study concluded that the Reynolds number and outlet pressure variables influenced on the behavior of the concentration polarization layer, however, the inlet solute concentration variable did not influence in a significant manner.