State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
School of Chemical Engineering and Chemistry, Harbin Institute of Technology, Harbin, 150090, China.
J Environ Manage. 2022 Nov 15;322:116067. doi: 10.1016/j.jenvman.2022.116067. Epub 2022 Aug 29.
In this study, a microbial fuel cell powered electro-Fenton system (MFCⓅEFs) was established in order to overcome the shortcomings of low electron flux and unexpected methane production, while simultaneously treating excess sludge (ES, substrate) and refractory syringic acid (SA). A strategy of co-adding lysozyme (LZ, as ES degradation catalyst) and 2-bromoethanesulfonate (BES, as methane inhibitor) into ES was optimized in MFCⓅEFs to maximize electron flux, microbial community diversity and functional gene abundance. The removal of sludge total chemical oxygen demand (TCOD) achieved 81.69% in 25 d under an optimal co-addition strategy (40.41 mg/gSS of LZ, 27.03 mmol/L of BES, adding on 22.8 h of the7th day), with a simultaneous high degradation of SA (99.30% in 25 h). Correspondingly, a maximum power density of 3.35 W/m was achieved (only 0.62 W/m from the control), which effectively realizes in-situ micro-electricity generation and utilization for bioelectric Fenton processes. Moreover, 42.25% of the total charges were employed for bio-electricity generation. The electricigens of Pseudomonas, Acinetobacter and Chlorobium showed effective enrichment, while the abundance of methanogenesis archaea was extremely decreased. Functional genes associated with methanogenesis including mtaA, hdra, and mcrA were effectively inhibited. The life cycle assessment along with an optimized co-addition strategy illustrated a beneficial environmental effect, particularly in terms of ecosystem quality and climate change. Above all, an enhanced synchronous degradation of excess sludge and refractory pollutants had been realized in a green and environmentally friendly way.
在这项研究中，建立了一种微生物燃料电池供电的电芬顿系统（MFC Ⓟ EFs），以克服电子通量低和甲烷产量不可预测的缺点，同时处理剩余污泥（ES，底物）和难处理的丁香酸（SA）。在 MFC Ⓟ EFs 中，优化了共添加溶菌酶（LZ，作为 ES 降解催化剂）和 2-溴乙磺酸钠（BES，作为甲烷抑制剂）的策略，以最大限度地提高电子通量、微生物群落多样性和功能基因丰度。在最佳共添加策略下（40.41 mg/gSS 的 LZ，27.03 mmol/L 的 BES，在第 7 天的 22.8 小时添加），经过 25 d 的处理，污泥总化学需氧量（TCOD）的去除率达到 81.69%，同时 SA 的降解率也很高（25 h 内达到 99.30%）。相应地，实现了 3.35 W/m 的最大功率密度（仅比对照低 0.62 W/m），有效地实现了生物电芬顿过程的原位微电流发电和利用。此外，总电荷的 42.25%用于生物发电。假单胞菌、不动杆菌和绿菌等电生成菌得到有效富集，而产甲烷古菌的丰度则极显著降低。与产甲烷作用相关的功能基因，包括 mtaA、hdra 和 mcrA，均得到有效抑制。沿优化共添加策略的生命周期评估表明，具有有益的环境效果，特别是在生态系统质量和气候变化方面。总之，以绿色环保的方式实现了剩余污泥和难处理污染物的同步强化降解。
