State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin, 150090, China; College of Life and Environmental Science, Wenzhou University, Wenzhou, 325035, China.
State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
Water Res. 2020 Aug 15;181:115903. doi: 10.1016/j.watres.2020.115903. Epub 2020 May 16.
To clarify the effect of the hydrophobic/hydrophilic polarity of extracellular polymeric substances (EPS) on sludge filterability improvement during SO/Fe oxidation, waste activated sludge (WAS), glucose-fed hydrophilic sludge (HPI-WAS), and sodium acetate-fed hydrophobic sludge (HPO-WAS) samples were cultivated, and their dewatering behaviors were individually explored. Experimental results showed that SO oxidation effectively disintegrated the polymeric EPS and led to a more significant reduction in the water content for HPO-WAS than for HPI-WAS (12.87-15.23% vs 9.31-12.12%), especially regarding the bound water (W) content. After oxidation, as high as 38.88-42.61% of the W within HPO-WAS samples were declined, much higher than the HPI-WAS samples (19.27-29.20%). Specifically, carbohydrates within sludge EPS negatively influenced the dewatering process of SO/Fe oxidation. By contrast, abundant existence of humic acids and polymeric proteinaceous components (especially those hydrophilic proteins and transitional humic acids) within the sludge EPS exhibited a converse trend. FT-IR and EEM spectral, as well as particle sizes variation for the sludge samples before and after SO/Fe oxidation was also evaluated. This study provides new insight into the enhancement of SO/Fe oxidation for sludge dewatering based on polarity analysis of EPS.
为了阐明细胞外聚合物（EPS）的疏水性/亲水性极性对 SO/Fe 氧化过程中污泥过滤性能改善的影响，培养了废活性污泥（WAS）、葡萄糖喂养的亲水性污泥（HPI-WAS）和乙酸钠喂养的疏水性污泥（HPO-WAS）样品，并分别探索了它们的脱水行为。实验结果表明，SO 氧化有效地破坏了聚合物 EPS，导致 HPO-WAS 的水分含量比 HPI-WAS 降低得更多（12.87-15.23%比 9.31-12.12%），尤其是结合水（W）的含量。氧化后，高达 38.88-42.61%的 HPO-WAS 样品中的 W 下降，远高于 HPI-WAS 样品（19.27-29.20%）。具体来说，污泥 EPS 中的碳水化合物会对 SO/Fe 氧化的脱水过程产生负面影响。相比之下，污泥 EPS 中丰富的腐殖酸和聚合蛋白质成分（尤其是那些亲水性蛋白质和过渡性腐殖酸）则表现出相反的趋势。还评估了 SO/Fe 氧化前后污泥样品的傅里叶变换红外光谱（FT-IR）和荧光激发发射矩阵光谱（EEM）以及颗粒尺寸变化。这项研究为基于 EPS 极性分析增强 SO/Fe 氧化以实现污泥脱水提供了新的见解。
