Ultrafiltration fouling reduction with the pilot-scale application of ozone preceding coagulation, flocculation, and sedimentation for surface water treatment

Abstract

A B S T R A C TAn ultrafiltration (UF) membrane process integrating ozone oxidation prior to a coagulation, flocculation, and sedimentation (CFS) pretreatment configuration processing surface water has been evaluated at the pilot-scale. Unlike prior research limited to short-term bench-scale evaluations, this current study provides information regarding the application of ozone oxidation prior to a CFS-UF pilot process operating over a four-month period (2,800 pilot runtime hours). In this work, changes in the long-term fouling behavior of the UF membrane process in response to the application of ozone prior to CFS pretreatment were characterized using fouling indices. When an average of 2.5 mg L −1 of ozone was applied prior to coagulation requiring 27 mg L −1 of polyaluminum chloride and a UF operating water flux of 85 L h −1 m −2 , the chemically reversible and hydraulically irreversible fouling indices increased by 59 and 40%, respectively. A reduction of chemically irreversible fouling concomitant with a continuous improvement of normalized specific flux was observed over 1,240 pilot runtime hours of ozone application. The total fouling index decreased by 41% as compared to the baseline CFS-UF configuration. This research indicates that the use of ozone oxidation prior to a CFS-UF configuration can reduce membrane fouling when integrated with conventional surface water treatment.

Preozonation Effects on Organic Foulants in a Coagulation–Ultrafiltration Membrane Process

“…These EEM results suggest that foulants that were less chemically irreversible were in the feedwater during the experiment with preozonation. These results agreed with recent pilot testing data that showed that ozone was specifically effective at reducing chemically irreversible fouling as opposed to hydraulically irreversible fouling (Biscardi et al 2016). Future research should expand this work to additional source waters to better understand the relationship between ozone, natural organic matter, and membrane fouling.…”

A novel PU/PVA-co-PE composite nanofiber membrane for water filtration

“…To meet the increasing water consumption of future generations, water treatment technologies with properties of environmental friendly, low cost, and high efficiency are extremely desirable [1][2][3]. In the past few decades, many techniques have been developed for the wastewater treatment, such as coagulation, sedimentation, evaporation, absorption, ion exchange, electrolysis, membrane technologies, and so on [4][5][6][7][8][9][10]. Due to the advantages of high efficiency, easy operation, and space saving, membrane separation technologies like microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO) have become the most attractive and promising methods for the wastewater treatment [1,11].…”