Effects of surface hydrophobicity on the removal of F-specific RNA phages from reclaimed water by coagulation and ceramic membrane microfiltration

Abstract

Microfiltration (MF) has been widely adopted as an advanced treatment process to reduce suspended solids and turbidity in treated wastewater effluents designated for potable reuse. Although microfilter pores are much larger than viruses, the addition of a coagulant upstream of a microfilter system can achieve stable virus removal. Ceramic membranes have a narrow pore size distribution to achieve the high removal of contaminants. This study aims to evaluate virus log reduction using bench-scale coagulation and ceramic membrane MF. To investigate the effects of differences in net surface hydrophobicity, 18 sewage-derived F-specific RNA phages (FRNAPHs) were used for batch hydrophobicity and coagulation–MF tests. The capability of bench-scale coagulation and ceramic membrane MF under continuous automated long-term operation was tested to remove the lab reference strain MS2 and three selected FRNAPH isolates which varied by surface property. Median virus log reduction values (LRVs) exceeding 6.2 were obtained for all three isolates and MS2. Although coagulation and hydrophobicity were positively correlated, the virus isolate demonstrating the lowest level of hydrophobicity and coagulation (genogroup I) still exhibited a high LRV. Thus, coagulation and ceramic membrane MF systems may serve as viable options for virus removal during water reclamation and advanced treatment.

Preparation of Ceramic Membranes and Their Application in Wastewater and Water Treatment

“…Ceramic membranes have a narrow pore-size distribution; therefore, they can effectively intercept viruses in water. Yasui et al [112] were able to achieve virus retention higher than 6.2 LRV with a coagulation and ceramic membrane MF system where the ceramic membrane had a pore size of 0.1 µm and a flux of 2.5 m/day (~100 LMH).…”

Unveiling the Viral Escape: Quantification of Microfloc-bound Viruses in Precoagulation and Membrane Filtration

“…(2023) reported a virus removal exceeding 6-log through a coagulation and ceramic MF system 12 . The coagulation process is recognized for its effectiveness in enhancing the removal rate of challenging substances, such as viruses and dissolved organic matter, which are di cult to eliminate through conventional membrane ltration 13,14 .…”