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市政污泥的处理已成为许多大城市的环境治理难题.本研究提出了基于热水解—真菌发酵—厌氧消化的三阶段精炼策略,旨在实现市政污泥的减量化和资源化.在市政污泥热水解处理中,当热水解温度由140 ℃升至180 ℃时,可以显著地提升市政污泥的减量效果和有机物的释放效率(p ＜ 0.05).市政污泥经过140 ℃、160 ℃和180 ℃两级热水解处理后,总挥发性固体(TVS)的去除率分别为36.6%、47.7%和58.5%,总有机碳(TOC)的溶解释放效率分别达到28.0%、38.0%和45.1%.在160 ℃下,污泥热水解上清液中的多糖和蛋白质的含量最为丰富,而在180 ℃时,由于在热水解过程中发生了美拉德反应,污泥热水解上清液的腐殖酸类物质的含量显著增加(p ＜ 0.05).采用黑曲霉(Aspergillus niger)进行真菌发酵,可以将市政污泥热水解上清液中的有机物转化为高附加值的菌丝纤维.在140 ℃和160 ℃下,污泥热水解上清液经过真菌发酵后,菌丝纤维的生物量分别达到1.30 g·L-1和1.27 g·L-1,对应的有机物转化率为24.6%和24.0%.从污泥热水解上清液真菌中回收的菌丝纤维可以用于生产纸基材料等高附加值产品.菌丝纤维纸结构致密,具有较好的力学性能,抗张强度可以达到10.75 N·m·g-1.在160 ℃下,污泥热水解上清液经真菌发酵耦合厌氧消化两级生物处理,能将热水解上清液超过75%的有机物进行综合利用以回收菌丝纤维和沼气.“,”Wastewater sludge creates a difficult environmental problem for many large cities. This study developed a three-phase innovative strategy for sludge treatment and reduction, including thermal hydrolysis, fun-gal fermentation, and anaerobic digestion. Increasing the temperature during the treatment from 140 to 180 ℃significantly improved the sludge reduction and organic release efficiencies (p ＜ 0.05, one-way analysis of variance (ANOVA) for the triplicate experiments at each temperature). After two cycles of thermal hydrolysis, the overall volatile solid reduction ratios of the sludge were 36.6%, 47.7%, and 58.5% for treatment at 140, 160, and 180°C, respectively, and the total organic carbon (TOC) conversion efficiency reached 28.0%, 38.0%, and 45.1%, respectively. The highest concentrations of carbohydrates and proteins were obtained at 160℃in sludge liquor, whereas the amount of humic substances significantly increased for the treatment at 180 ℃(p ＜0.05, one-way ANOVA for the triplicate experiments at each temperature) due to the Maillard reaction. Fungal fermentation of the hydrolyzed sludge liquor with Aspergillus niger converted the waste organics to valuable fiber materials. The biomass concentration of fungal hyphae reached 1.30 and 1.27 g?L 1 in the liquor of sludge treated at 140 and 160°C, correspond-ing to organic conversion ratios of 24.6% and 24.0%, respectively. The fungal hyphae produced from the sludge liquor can be readily used for making papers or similar value-added fibrous products. The paper sheets made of hyphae fibers had a dense structure and strong strength with a tensile strength of 10.75 N?m?g 1. Combining fungal fermentation and anaerobic digestion, the overall organic utilization efficiency can exceed 75% for the liquor of sludge treated at 160°C.