Optimization of hollow fibers membrane wastewater treatment: An experimental study

This paper presents the results of a study aimed at estimating the efficiency of the ultrafiltration process for the treatment of secondary effluents to be reused in wet textile industries. This approach was experienced at pilot scale at Baciacavallo wastewater treatment plant in Prato (Italy). During the experimental trials the membrane filtration process was optimized in terms of running time, backwash, chemicals addition, cleaning procedures and running cost. A transmembrane pressure of 270 mbar and a hydraulic permeability of 200 l/(h bar m2) were ensured. According to the experimental results the treatment guaranteed the compliance with the target values for wastewater reuse in wet textile industries. Mathematical tools were used to simulate the efficiency of the hydraulic properties, showing different behaviors of the filters by varying the process parameters (such as filtration time and flux), so that the selection of the best configuration can be approached easier and faster. The process was optimized both in terms of volume of treated water and energy costs, providing an accurate procedure to improve the filter performance: an example of application is reported, where the volume of treated water can be increased by 43% reducing the 45.5% of the energy cost.

► We investigated the efficiency of an innovative process of ultrafiltration.
► The estimate of the efficiency is achieved using both modelling and experimental trials.
► An optimization procedure is defined to improve hydraulic and energy performance of the membranes.