ORIGINAL PAPER New treatment at source approach using combination of microfiltration and nanofiltration for dyeing effluents reuse G. Masmoudi • R. Trabelsi • E. Ellouze • R. B. Amar Received: 10 August 2012 / Revised: 25 March 2013 / Accepted: 23 April 2013 / Published online: 17 May 2013 Ó Islamic Azad University (IAU) 2013 Abstract Textile effluents are considered among the most polluted wastewaters all over the world. Among different textile processes, dyeing is the operation that produces the most important amounts of chemical pollution. Many studies have been carried out toward the treatment of these hazardous effluents, and a variety of techniques have been applied for this aim. In this work, the effluents coming from different steps of the dyeing cycle were treated following different mixtures of baths using membrane technology. Nanofiltration (NF) experiments were performed for color removal, but membrane fouling still a major limitation. To enhance NF performances, microfiltration (MF) was carried out as pretreatment to NF. The results showed almost above 99 % of color and turbidity removal and also an important decrease in COD, chloride and salts contents with an improvement in the MF and NF stabilized fluxes of different mixtures compared to that corresponding to the dyeing effluent treated separately. In order to accomplish a full reuse cycle, dyeing experiments were performed using the combined system (MF/NF) permeates. Results were eval- uated regarding total color difference between samples and a standard test done with fresh water. Keywords Baths mixtures  Dyeing cycle  Microfiltration  Nanofiltration  Reuse Introduction In order to achieve a finished product, the textile item has to undergo through different processing stages, but dyeing remains the most important. Industrial dyeing process includes several operations such as pretreatment, dyeing, washing, neutralizing and softening. Some operations are followed by one or more rinsing step. Therefore, large amounts of water have to be used to achieve the dyeing cycle. Alle `gre et al. (2006) noticed that 1 kg of cotton requires an average of 70–150 l of fresh water. Reactive dyes are widely used for dyeing cellulose as well as cotton fibers. However, in this case, the dyeing process requires large amounts of salts and dyes to achieve a good product quality: 1 kg of cotton requires 0.6 kg of NaCl and 40 g of reactive dye (Alle `gre et al. 2006). Direct discharge of the generated effluents into the environment can cause irreversible ecological problems such as eutrophication and anarchic algae proliferation in the aquatic systems (Khataee et al. 2010) and can have disastrous effects on potable water even in the deepest aquifers. So, there is a stringent need to suitably treat the dyeing effluents before discharge. Membrane treatment is relatively a recent technology, but it is shown to be efficient for the treatment of the dyeing effluents (Uzal et al. 2009; Katarzyna 2010). Textile wastewater reuse is strongly related with membrane pro- cesses, especially nanofiltration (NF) process which has been widely studied (Tang and Chen 2002; Wenzel et al. 1996; Zahrim et al. 2011). Because of the reduced pore size of NF membrane (almost 10 -9 m) against the important pollutant charge of the dyeing effluent, membrane fouling represents the major limitation for the use of single NF treatment. Fouling is susceptible to damage the membrane and reduce its life time also it leads to high operational G. Masmoudi  R. Trabelsi  E. Ellouze  R. B. Amar (&) Laboratory of Material Sciences and Environment, Faculty of Sciences of Sfax, Soukra road km 4, 3000 Sfax, Tunisia e-mail: Raja.rekik@fss.rnu.tn 123 Int. J. Environ. Sci. Technol. (2014) 11:1007–1016 DOI 10.1007/s13762-013-0303-3