Nanofiltration of low-contaminated textile rinsing effluents for on-site treatment and reuse

Intensive water-demanding industries require an effective management of water sources and wastes in order to implement as much recovery as possible with the quality standards of the production activity. Besides the application of good environmental practices pursued by the IPPC Directive, an optimal methodological solution for each industrial site has to be applied in order to minimize the discharge and produce an alternative water source at the same time. This work presents operational data on the treatment of five different representative effluents from rinsing operations of textile finishing processes. Membrane filtration of separate effluent streams was tested at pilot scale to obtain data on flow rate, fouling tendency, durability and quality of the permeate. Comparison among different membrane types was performed at bench scale, and pilot runs were carried out on the selected membrane. A cost evaluation of the preliminary design of treatment works obtained up-scaling the operational indexes is reported as well. Nanofiltration of the investigated effluents proved to be a cost-efficient way to assure constant good water quality demanded by textile finishing processes.