Ultrafiltración de efluentes de la industria textil. Estudio de los parámetros de operación y mecanismos de ensuciamiento

En la presente Tesis Doctoral se ha llevado a cabo el estudio de la etapa de ultrafiltración mediante membranas cerámicas para el tratamiento de aguas residuales de la industria textil, como etapa previa a la nanofiltración, con vías a su reutilización. En concreto se ha profundizado en el ensuciamiento de las membranas bajo distintas condiciones de operación (presión transmembranal, velocidad tangencial, composición del alimento, pH, temperatura y umbral de corte molecular de las membranas). Para ello se han utilizado efluentes sintéticos de distinta complejidad, simulando los efluentes reales. De este modo se facilita el estudio de los mecanismos de ensuciamiento implicados, así como de las interacciones existentes entre los distintos componentes entre sí y con las membranas. En el estudio se ha comprobado que ciertas condiciones de operación (PTM, MWCO, concentración de materia orgánica y de sal elevados, así como VT bajas) favorecen el ensuciamiento de las membranas y disminuyen el rechazo de solutos. También otros parámetros como la temperatura o el pH influyen notablemente en el comportamiento de la membrana. Sin embargo, se ha observado que no sólo las condiciones de operación afectan al rendimiento del proceso, sino que también las interacciones electroestáticas soluto-soluto y membrana-soluto juegan un papel importante en cuanto al ensuciamiento y la selectividad de las membranas. Mediante el proceso de UF se consigue una importante reducción de la DQO, una moderada reducción de color y una retención de sal insignificante, obteniéndose un permeado que debe someterse a un tratamiento posterior de NF u OI, dependiendo de la calidad requerida, para su posible reutilización. El estudio se ha completado evaluando la etapa de nanofiltración para el tratamiento directo de varios efluentes sintéticos de diversa complejidad mediante dos tipos de membranas cerámicas, de distinto material y MWCO, observando que tanto el tamaño de poro como el material influyen en su comportamiento. En dicha etapa se obtiene, con la membrana de menor MWCO, un permeado libre de color y materia orgánica y rico en sal, apto para su reutilización en los procesos textiles. Por otra parte se ha desarrollado y validado, mediante medidas de flujo y análisis microscópico, el protocolo de limpieza química para la recuperación de la permeabilidad inicial de las membranas estudiadas tras el ensuciamiento. Además, mediante un estudio estadístico se han optimizado las condiciones de operación de un proceso de limpieza físico que implica el uso de ultrasonidos.Alventosa De Lara, E. (2015). Ultrafiltración de efluentes de la industria textil. Estudio de los parámetros de operación y mecanismos de ensuciamiento [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48537TESI

Evolution of Membrane Performance During the Ultrafiltration of Reactive Black 5 Solutions: Effect of Feed Characteristics and Operating Pressure

[EN] In the present work, the feasibility of the ultrafiltration (UF) technology for the removal of a hazardous azo reactive dye, Reactive Black 5 (RB5), was studied. A tubular UF ceramic membrane was used to filter RB5 aqueous solutions. Solutions at different feed concentrations (50, 100, 500 mg/L) and temperatures (25, 30, 35, 40 °C) were tested in order to observe the influence of these two parameters on the evolution of permeate flux and dye rejection with operating time. Moreover, the effect of transmembrane pressure (TMP) was also studied by performing essays at different operating pressures (1, 2, 3, 4 bar). Additionally, membrane performance was also evaluated by means of the average permeate flux and the cumulative flux decline. The results showed that both the productivity and the permeate quality improved by increasing feed temperature and decreasing feed concentration. On the other hand, an increase in TMP led to an increase in permeate flux. However, in this case the flux decline was more pronounced and the retention of dye decreased. Finally, the relatively high dye rejections obtained are an indicator of the suitability of UF technology for the removal of RB5 from aqueous solutions as a pretreatment of other membrane processes to textile water reuse. Copyright © 2012, AIDIC Servizi S.r.l.This work was supported by the “Ministerio de Ciencia e Innovación” through the project ref. CTM2009-13048 and the “Ministerio de Educación” through the FPU grant ref. AP2009-3509.Alventosa De Lara, E.; Barredo Damas, S.; Alcaina Miranda, MI.; Iborra Clar, MI. (2012). Evolution of Membrane Performance During the Ultrafiltration of Reactive Black 5 Solutions: Effect of Feed Characteristics and Operating Pressure. Chemical Engineering Transactions. 29:1285-1290. https://doi.org/10.3303/CET1229215S128512902

Studio delle reazioni scr per post-trattamento di gas di scarico da motori Diesel su catalizzatore monolítico a base di Cu-Zeolite

Consulta en la Biblioteca ETSI Industriales (8191)Alventosa De Lara, E. (2009). Studio delle reazioni scr per post-trattamento di gas di scarico da motori Diesel su catalizzatore monolítico a base di Cu-Zeolite. http://hdl.handle.net/10251/33447.Archivo delegad

Tratamiento de disoluciones coloreadas mediante ultrafiltración con membranas cerámicas. Estudio del efecto de los parámetros de operación

El presente trabajo de investigación se ha desarrollado con el objetivo de estudiar el tratamiento de disoluciones coloreadas modelo, simulando el efluente proveniente de la industria textil, mediante ultrafiltración con membranas cerámicas, analizando el ensuciamiento de las membranas así como el efecto de distintos parámetros de operación.Alventosa De Lara, E. (2010). Tratamiento de disoluciones coloreadas mediante ultrafiltración con membranas cerámicas. Estudio del efecto de los parámetros de operación. http://hdl.handle.net/10251/13642Archivo delegad

Study and optimization of the ultrasound-enhanced cleaning of an ultrafiltration ceramic membrane through a combined experimental statistical approach

Membrane fouling is one of the main drawbacks of ultrafiltration technology during the treatment of dye-containing effluents. Therefore, the optimization of the membrane cleaning procedure is essential to improve the overall efficiency. In this work, a study of the factors affecting the ultrasound-assisted cleaning of an ultrafiltration ceramic membrane fouled by dye particles was carried out. The effect of transmembrane pressure (0.5, 1.5, 2.5 bar), cross-flow velocity (1, 2, 3 m s−1), ultrasound power level (40%, 70%, 100%) and ultrasound frequency mode (37, 80 kHz and mixed wave) on the cleaning efficiency was evaluated. The lowest frequency showed better results, although the best cleaning performance was obtained using the mixed wave mode. A Box Behnken Design was used to find the optimal conditions for the cleaning procedure through a response surface study. The optimal operating conditions leading to the maximum cleaning efficiency predicted (32.19%) were found to be 1.1 bar, 3 m s−1 and 100% of power level. Finally, the optimized response was compared to the efficiency of a chemical cleaning with NaOH solution, with and without the use of ultrasound. By using NaOH, cleaning efficiency nearly triples, and it improves up to 25% by adding ultrasound.This research has been financially supported by the Spanish Ministerio de Ciencia e Innovacion (MICINN) through the Project Ref. CTM2009-13048. The authors of this work also acknowledge the assistance of the Spanish Ministerio de Educacion for the award of a F.P.U. Grant (Ref. AP2009-3509).Alventosa De Lara, E.; Barredo Damas, S.; Alcaina Miranda, MI.; Iborra Clar, MI. (2014). Study and optimization of the ultrasound-enhanced cleaning of an ultrafiltration ceramic membrane through a combined experimental statistical approach. Ultrasonics Sonochemistry. 21(3):1222-1234. https://doi.org/10.1016/j.ultsonch.2013.10.022S1222123421

Factors influencing the Ultrasound-enhaced cleaning process of an ultrafiltration ceramic membrane fouled by Reactive Dye Particles

This work was supported by the "Ministerio de Ciencia e Innovación" through the project ref. CTM2009-13048 and the "Ministerio de Educación" through the FPU grant ref. AP2009-3509.Alventosa De Lara, E.; Barredo Damas, S.; Alcaina Miranda, MI.; Iborra Clar, MI. (2012). Factors influencing the Ultrasound-enhaced cleaning process of an ultrafiltration ceramic membrane fouled by Reactive Dye Particles. Procedia Engineering. 44:1665-1667. doi:10.1016/j.proeng.2012.08.901S166516674

Ultrafiltration ceramic membrane performance during the treatment of model solutions containing dye and salt

The present study reports the results of the ultrafiltration with a ceramic membrane of model solutions containing NaCl and a reactive dye, which simulate textile wastewaters. The effect of salt concentration (1, 2.5 and 4 g/L NaCl) and transmembrane pressure (1, 2, and 3 bar) on the evolution over time of both permeate flux and solutes rejection was tested. Membrane fouling was also investigated in terms of analysis of resistances-in-series, determining the contribution of both reversible and irreversible fouling under any condition tested. More severe flux decline and a slight reduction in color rejection were observed under higher pressure. Furthermore, it was demonstrated that the membrane performance was significantly worsened in the presence of salt, according to permeate flux, dye rejection and the values of the different resistances. Higher flux decline and total resistance together with lower color removal were observed when adding NaCl to the solution. These results were attributed to membrane charge and repulsion-attraction phenomena. It was then suggested that electrostatic interactions between the solutes and the membrane materials have an important role in the ultrafiltration performance, as well as influencing the kind of fouling affecting the membrane.This research was financially supported by the Spanish Ministerio de Ciencia e Innovacion (MICINN) through the Project ref. CTM2009-13048. The authors of this work would also thank the Spanish Ministerio de Educacion for the award of a F.P.U. grant (Ref. AP2009-3509).Alventosa De Lara, E.; Barredo Damas, S.; Zuriaga Agustí, E.; Alcaina Miranda, MI.; Iborra Clar, MI. (2014). Ultrafiltration ceramic membrane performance during the treatment of model solutions containing dye and salt. Separation and Purification Technology. 129:96-105. https://doi.org/10.1016/j.seppur.2014.04.0019610512

Performance of ceramic ultrafiltration membranes and fouling behavior of a dye-polysaccharide binary system

Ultrafiltration membrane processes have become an established technology in the treatment and reuse of secondary effluents. Nevertheless, membrane fouling arises as a major obstacle in the efficient operation of these systems. In the current study, the performance of tubular ultrafiltration ceramic membranes was evaluated according to the roles exerted by membrane pore size, transmembrane pressure and feed concentration on a binary foulant system simulating textile wastewater. For that purpose, carboxymethyl cellulose sodium salt (CMC) and an azo dye were used as colloidal and organic foulants, respectively. Results showed that a larger pore size enabled more solutes to get adsorbed into the pores, producing a sharp permeate flux decline attributed to the rapid pore blockage. Besides, an increase in CMC concentration enhanced severe fouling in the case of the tighter membrane. Concerning separation efficiency, organic matter was almost completely removed with removal efficiency above 98.5%. Regarding the dye, 93% of rejection was achieved. Comparable removal efficiencies were attributed to the dynamic membrane formed by the cake layer, which governed process performance in terms of rejection and selectivity. As a result, none of the evaluated parameters showed significant influence on separation efficiency, supporting the significant role of cake layer on filtration process.This research has been financially supported by the Spanish Ministerio de Ciencia e Innovacion (MICINN) through the project ref. CTM2009-13048. The authors of this work also acknowledge the assistance of the Spanish Ministerio de Educacion for the award of a F.P.U. grant (Ref. AP2009-3509).Zuriaga Agusti, E.; Alventosa De Lara, E.; Barredo Damas, S.; Alcaina Miranda, MI.; Iborra Clar, MI.; Mendoza Roca, JA. (2014). Performance of ceramic ultrafiltration membranes and fouling behavior of a dye-polysaccharide binary system. Water Research. 54:199-210. doi:10.1016/j.watres.2014.01.064S1992105