Deep dewatering of waste activated sludge (WAS) is still a challenge due to high content of bound water and non-Newton fluid properties of sludge flocs. Electro-Fenton (EF) can enhance sludge dewaterability, however, low pH needed in homogeneous EF and fine flocs after EF conditioning influenced deep dewatering of sludge and the subsequent resource recovery disposal. In this study, a three dimension electro-Fenton (3D-EF) using Fe modified sludge biochar (Fe@SBC) as particle electrode, heterogeneous Fenton catalyst and skeleton builder for deep dewatering of sludge under neutral pH was proposed. Fe@SBC obtained at 800 °C exhibited high capacity of H₂O₂ electrogeneration and activation due to high conductivity and content of 2e-ORR selectivity functional groups. With promoted generation of H₂O₂ and hydroxyl radical (•OH), 3D-EF with Fe@SBC showed higher decomposition of bound extracellular polymeric substances (EPS) and disintegration of cells in sludge flocs, resulting in releasing bound and intracellular water into free water. Compared with EF, 3D-EF with Fe@SBC800 had higher ability in breaking macromolecules of protein and polysaccharide, as well as removing -COOH and -NH₂ groups in EPS, which could facilitate release of bound water trapped in EPS and self-coagulation of fine flocs. During subsequent filtering process, Fe@SBC could enhance sludge filterability as skeleton builder. A synergetic effect of strong oxidation and physical conditioning were proposed in 3D-EF sludge dewaterability with Fe@SBC, and the improved oxidation by Fe@SBC was supposed to play the major role.

由于污泥絮凝物的结合水含量高和非牛顿流体特性，废活性污泥 (WAS) 的深度脱水仍然是一个挑战。电芬顿 (EF) 可以提高污泥的脱水能力，但是，经过 EF 调节后均质 EF 和细絮状物所需的低 pH 值影响了污泥的深度脱水和随后的资源化处理。在这项研究中，提出了一种三维电芬顿 (3D-EF)，使用 Fe 改性污泥生物炭 (Fe@SBC) 作为粒子电极、非均相芬顿催化剂和骨架助剂，用于在中性 pH 条件下对污泥进行深度脱水。在 800 °C 下获得的 Fe@SBC 表现出高 H ₂ O _2容量由于高电导率和 2e-ORR 选择性官能团的含量而产生电和活化。随着 H ₂ O ₂和羟基自由基 (•OH) 的产生，Fe@SBC 的 3D-EF 显示出结合的细胞外聚合物 (EPS) 的更高分解和污泥絮凝物中细胞的解体，导致结合水和细胞内水释放到免费水。与EF相比，Fe@SBC800的3D-EF对蛋白质和多糖大分子的破坏能力更强，对-COOH和-NH _{2的去除能力更强}EPS 中的基团，这可以促进 EPS 中捕获的结合水的释放和细絮状物的自凝结。在随后的过滤过程中，Fe@SBC 作为骨架助剂可以提高污泥的过滤性。Fe@SBC 在 3D-EF 污泥脱水性能中提出了强氧化和物理调节的协同效应，Fe@SBC 的改善氧化作用应该起主要作用。