Hollow fiber membrane ultrafiltration of a simulated secondary treatment wastewater. Process and fouling modeling

Abstract

It is well known that there is a scarcity of drinking and irrigation water around the world nowadays. According to the United Nations, water scarcity affects 1.2 billion people (one-fifth of the world's population) and the water use has been growing at twice the rate of population increase in the last century.

This fact makes the reuse of the wastewater from municipal wastewater treatment plants (MWTPs) an interesting option. Ultrafiltration after the secondary settling is becoming more frequently used for wastewater reclamation and it has some advantages compared with conventional processes such as compact design and high quality of the final effluent (including microbiological parameters).

However, membrane fouling aspects have to be more deeply studied in view to a more prolonged membrane life. For it, modeling of the process is of crucial importance.

Thus, the effect of the operating conditions in the ultrafiltration membrane fouling has been reported by several authors in the bibliography (Wang et alter [1]).

In this work, a hollow fiber membrane module has been applied to the ultrafiltration of a simulated secondary effluent from a MWTP. The water quality and the membrane fouling were investigated. This work is focused on the effect of transmembrane pressure and the cross-flow velocity on membrane permeability.

In addition, in order to model the ultrafiltration fouling process, permeate flux versus time data has been fitted to a Belfort model.