School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, Jiangsu, China.
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, Jiangsu, China; Jiangxi Jindalai Environmental Protection Co., Ltd, Nanchang, 330100, Jiangxi, China; School of Environmental and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China.
J Environ Manage. 2023 Sep 1;341:118079. doi: 10.1016/j.jenvman.2023.118079. Epub 2023 May 5.
The recovery of volatile fatty acids (VFAs) through anaerobic fermentation (AF) is usually restricted by the poor biodegradability of waste activated sludge (WAS). This study proposed a novel strategy, i.e. peroxymonosulfate (PMS) activated by Fe-loaded sodium alginate hydrogel beads (Fe-SA), to enhance AF performance. Experimental results demonstrated that the as-synthesized Fe-SA and PMS co-pretreatment synergistically enhanced WAS solubilization and VFAs production. The maximal VFAs yield of 2013 mg COD/L was achieved at the Fe-SA dosage of 4.0 mM/g TSS, which was 93.7% higher than that with sole PMS addition and 8.82 times higher than that of the control. Mechanistic studies elucidated that the generation of reactive radicals such as SO and OH from PMS was greatly induced by Fe-SA, which contributed to WAS disintegration and degradation of refractory compounds. Additionally, analysis of the key enzyme activities indicated that the Fe-SA could strengthen biological hydrolysis and acidogenesis of sludge during AF. Microbial analysis illustrated that Fe-SA evidently improved the abundances of fermentative microorganisms as well as functional gene expression via creating a favorable environment for microbial growth. This study demonstrated the applicable potential of Fe-SA hydrogel beads activating PMS for VFAs production and provides an important reference for developing advanced oxidation processes-based application in AF.
通过厌氧发酵（AF）回收挥发性脂肪酸（VFAs）通常受到废活性污泥（WAS）生物降解性差的限制。本研究提出了一种新策略，即用负载铁的海藻酸钠水凝胶珠（Fe-SA）激活过一硫酸盐（PMS），以增强 AF 性能。实验结果表明，所合成的 Fe-SA 和 PMS 共同预处理协同增强了 WAS 的溶解和 VFAs 的产生。在 Fe-SA 用量为 4.0 mM/gTSS 时，获得了 2013 mg COD/L 的最大 VFAs 产率，比单独添加 PMS 高 93.7%，比对照高 8.82 倍。机理研究表明，Fe-SA 极大地诱导了 PMS 产生的活性自由基，如 SO 和 OH，这有助于 WAS 的解体和难降解化合物的降解。此外，关键酶活性分析表明，Fe-SA 通过为微生物生长创造有利环境，在 AF 过程中可以增强污泥的生物水解和产酸作用。微生物分析表明，Fe-SA 通过创造有利于微生物生长的环境，显著提高了发酵微生物的丰度和功能基因的表达。本研究证明了 Fe-SA 水凝胶珠激活 PMS 用于 VFAs 生产的应用潜力，并为基于高级氧化工艺在 AF 中的应用提供了重要参考。
