Micro and Nan0 Filtration of Secondary Textileldomestic Effluents for Reuse

Ceramic microfiltration (MF) followed by nanofiltration (NF) was tested at pilot scale as a polislung posttreatment of secondary effluents (textilddomestic wastewater) in order to obtain a water to be reused in the textile industry. According to hs study, a 2 stages (h4F + NF) membrane filtration allows to produce a polished effluent which can be reused in the most demandmg textile industry (silk). Contrary to other traditional processes used for suspended solids removal, the ceramic MF module does not require any addition of chemicals. It can operate without major fouling problems at satisfactory fluxes, of the order of 100 150 1 m-2h-1, if the operating parameters (crossflow velocity and transmembrane pressure) are adequately controlled. Chemical cleaning was required only once a week. With a alkaline + acid cleaning carried out at high temperature (60 70°C) the module permeability was restored without problems. Because of its constant quahty, the MF permeate was an ideal feed for the NF plant ~ c h operated for long cycles giving a satisfactory final product without f o h g problems.