Novel strategies for improving permeate flux and water quality of gravity-driven membrane (GDM) filtration

Abstract

Climate change, population growth, and urbanization have led to an increasingly thirsty world. There is a growing demand for innovative water technologies to solve the global water shortage issue. Gravity-driven membrane (GDM) filtration is a new concept of low-energy and decentralized water treatment technology based on the membrane filtration. GDM enables stable water production for months to years with minimal maintenance and energy consumption. Nevertheless, the low permeate flux and poor removal of dissolved contaminants limit the widespread application of GDM. The goal of this thesis work was to investigate novel strategies to improve the flux and permeate quality performance of GDM filtration. The strategies were based on parameters affecting GDM filtration, including membrane characteristics, module configuration, membrane relaxation, and preoxidation with chlorine and ozone. This study demonstrates that better understanding parameters affecting the membrane fouling formation and biological fouling control can be the basis for strategies to improve the permeate flux of GDM filtration. Further investigation of preoxidation effects on the permeate water quality should enable prediction of additional removal efficiency of aquatic contaminants and help to suggest new strategies for improving the performance of GDM filtration. Considering the superior performance of the parameters influencing GDM filtration, this information exemplifies effective strategies to improve performance of GDM filtration.