Effects of Coagulation on the Ceramic Membrane Fouling during Surface Water Treatment

Abstract

Evaluating the pretreatment conditions and fouling behavior is a prerequisite to the effective implementation of the coagulation-ceramic membrane hybrid processes for surface water treatment. Little is known about the performance of the hybrid processes; previous studies have dealt mainly with polymeric membranes. A coagulation-ceramic microfiltration system performed better in the treatment of select U.S. surface waters than a polymeric counterpart in terms of relative pressure in a constant-flux mode and normalized flux in a constant-pressure mode. The operating pressure for the filtration of river waters with the ceramic membrane system was 2.1–2.8 times the pressure for pure water, while it was 3.7–5.6 times with the polymeric membrane system, and the normalized flux in a constant pressure mode was higher with the ceramic membrane system (0.54 and 0.44 for ceramic and polymeric systems, respectively). Less severe fouling and higher cleaning efficiency observed in the ceramic hybrid system suggest that the coagulation would be a robust pretreatment option for the application of ceramic filtration for the surface water treatment.