TY - JOUR
T1 - The synergistic fouling of ceramic membranes by particles and natural organic matter fractions using different surface waters in South Africa
AU - Moyo, Welldone
AU - Chaukura, Nhamo
AU - Motsa, Machawe M.
AU - Mthombeni, Nomcebo H.
AU - Msagati, Titus A.M.
AU - Mamba, Bhekie B.
AU - Heijman, Sebastiaan G.J.
AU - Nkambule, Thabo T.I.
PY - 2021
Y1 - 2021
N2 - This study demonstrates the fundamental differences in fouling development and mechanisms of unfiltered and 0.45 µm pre-filtered water samples on ceramic membranes. Robust characterization of the feed waters was conducted using gravimetric analysis, optical methods and modeling techniques. UV254 removal and suspended solids (SS) for the unfiltered samples presented a strong correlation (R2 = 0.87). Further, SS exhibited strong correlations with fluorescent fractions (R2 = 0.82; 0.81 and 0.74 for C1; C2 and C3, respectively). This observation confirmed the significance of inorganic particles in the development of a combined fouling layer with fluorescent organic components. The fouling development rate for water sampled from Plattenburg Bay (PL) was higher than the rest of the 0.45 µm pre-filtered samples. This was attributed to the low conductivity (175 µS.m-1) of the water sample, translating to a low ionic strength environment. Samples collected from Hermanus River (HL) and Lepelle River (OL) had similar SS quantity (87.6 mg/L and 88.4 mg/L, respectively), and modified fouling index (MFI) values for raw samples were 6625 and 8060 s/L2, respectively, despite a very large difference in the content of organic matter (22.67 mg/L.C and 9.81 mg/L.C). This could be due to organic matter attaching onto the surface of particles and reducing the adsorption of NOM within membrane pores and/or onto the membrane active layer. This study demonstrated the extent of in situ background electrolytes, foulant concentration, foulant-foulant interactions, foulant-membrane interaction and physicochemical properties of feed stream on fouling development and mechanisms.
AB - This study demonstrates the fundamental differences in fouling development and mechanisms of unfiltered and 0.45 µm pre-filtered water samples on ceramic membranes. Robust characterization of the feed waters was conducted using gravimetric analysis, optical methods and modeling techniques. UV254 removal and suspended solids (SS) for the unfiltered samples presented a strong correlation (R2 = 0.87). Further, SS exhibited strong correlations with fluorescent fractions (R2 = 0.82; 0.81 and 0.74 for C1; C2 and C3, respectively). This observation confirmed the significance of inorganic particles in the development of a combined fouling layer with fluorescent organic components. The fouling development rate for water sampled from Plattenburg Bay (PL) was higher than the rest of the 0.45 µm pre-filtered samples. This was attributed to the low conductivity (175 µS.m-1) of the water sample, translating to a low ionic strength environment. Samples collected from Hermanus River (HL) and Lepelle River (OL) had similar SS quantity (87.6 mg/L and 88.4 mg/L, respectively), and modified fouling index (MFI) values for raw samples were 6625 and 8060 s/L2, respectively, despite a very large difference in the content of organic matter (22.67 mg/L.C and 9.81 mg/L.C). This could be due to organic matter attaching onto the surface of particles and reducing the adsorption of NOM within membrane pores and/or onto the membrane active layer. This study demonstrated the extent of in situ background electrolytes, foulant concentration, foulant-foulant interactions, foulant-membrane interaction and physicochemical properties of feed stream on fouling development and mechanisms.
KW - Fluorescent organic matter
KW - Membrane fouling resistance
KW - Modified fouling index
KW - Particulate organic matter
KW - Synergistic fouling
UR - http://www.scopus.com/inward/record.url?scp=85104668699&partnerID=8YFLogxK
U2 - 10.22079/JMSR.2020.127635.1384
DO - 10.22079/JMSR.2020.127635.1384
M3 - Article
AN - SCOPUS:85104668699
SN - 2476-5406
VL - 7
SP - 125
EP - 137
JO - Journal of Membrane Science and Research
JF - Journal of Membrane Science and Research
IS - 2
ER -