Dynamic evolution of reverse osmosis membrane fouling in sugar mill condensate purification: Quantifying the contribution of organic, inorganic, and biological fouling

Reverse osmosis is an effective method for purifying sugar mill condensate (SMC), but membrane fouling challenges its long-term stability. This study analyzes the dynamic evolution of fouling during SMC treatment, examining changes in membrane properties like flux, roughness, hydrophilicity, morphology, and the composition of the foulant layer (organic, inorganic, biological components). Multiple linear regression coupled with variance partitioning analysis is used to quantify the individual and interactive contributions of various fouling factors, collectively explaining approximately 91 % of the variance in fouling behavior. Individual organic fouling (mainly proteins and polysaccharides) accounts for 9.0 %, binary organic-biological fouling (in the form of microorganism-polysaccharides) for 33.4 %, and ternary organic-inorganic-biological fouling (in the form of microorganism-polysaccharides-K/Fe) for 47.6 %. The results indicate that organic fouling plays a central role throughout the fouling process. Redundancy analysis explores the interactions among fouling factors, membrane properties, and operating times, dividing fouling evolution into three stages: initial individual organic fouling, predominant organic-biological fouling, and the establishment of stable ternary fouling. These insights provide valuable guidance for developing strategies to mitigate membrane fouling in SMC. [Display omitted] •Studied RO membrane fouling in sugar mill condensate purification•Quantified contributions of organic, inorganic, and biological fouling•Organic fouling plays a central role in the overall fouling process.•Statistical analysis divided the fouling process into three stages.