Control behavior of pretreatment on ceramic membrane fouling caused by different organic substances

Abstract

To guide the practical application of ozonation and adsorption coupled with ceramic membrane technology, the mitigation mechanisms of O3 pre-oxidation, powdered activated carbon (PAC) pre-adsorption, and combined O3-PAC pretreatment on membrane fouling caused by natural organic matter (NOM) were investigated. The membrane and water quality were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), three-dimensional fluorescence-parallel factor analysis (PARAFAC-EEM), dissolved organic carbon (DOC), laser particle size and Zeta potential. Results showed that the membrane flux decline caused by humic acid (HA), sodium alginate (SA), bovine serum albumin (BSA) and surface water were alleviated by 35.2%, 55.2%, 31.0% and 59.0% after O3-PAC pretreatment. Meanwhile the removal rates of HA, SA and BSA were 26.2, 74.8% and 42.3%, respectively. The combination of PAC and O3 can effectively control the membrane fouling caused by HA and SA. Ozonation can degrade organic matter into small molecules, and PAC has high adsorption to these small molecules, by recycling PAC can take away this part of organic matter, thereby reducing membrane fouling. O3 showed no obvious advantage for membrane fouling caused by BSA, and the decrease of membrane fouling was mainly attributed to the adsorption of PAC. This investigation highlights the potential mechanism of O3-PAC in alleviating the membrane fouling caused by different organic compounds, contributing to the efficient and low-carbon operation of the production.