Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education,School of Environmental Science and Technology, Dalian University of Technology

当前厌氧消化的核心技术原理是种间氢传递(IHT),其对扩散传质依赖高,在处理城镇有机固废(MOSW,主要包括餐厨垃圾和剩余污泥)时易受阻,导致厌氧产甲烷停滞。直接种间电子传递(DIET)对扩散传质依赖低,可取代IHT,成为城镇有机固废厌氧产甲烷的主要工作模式。乙醇型发酵预处理和投加碳基导电材料是促进厌氧消化中DIET的两大手段。以实际城镇有机固废为底物,采用乙醇型发酵预处理耦合生物炭的方法,对强化厌氧产甲烷性能进行探究。结果显示:(1)通过优化酿酒酵母培养时间、接种比及培养基组成,获得了酿酒酵母的最佳培养条件(培养时间为21.17h,接种比为15%,每30mL液体培养基组成为3.00g葡萄糖、0.12g蛋白胨、0.12g酵母浸出粉及微量元素);(2)通过优化乙醇型发酵预处理的温度和酿酒酵母的接种比,获得了乙醇型发酵预处理的最佳工艺条件(最佳发酵温度为37℃,酿酒酵母接种比为20mL/L);(3)设计半连续流厌氧消化实验,探究乙醇型发酵预处理耦合生物炭对城镇有机固废甲烷产量和底物去除的影响。相比于对照组,乙醇型发酵预处理(接种20mL/L酿酒酵母)耦合生物炭(2g/L)组的甲烷产量提高了102.50%,底物去除率提高了16.15%;(4)微生物群落分析发现,乙醇型发酵预处理耦合生物炭提高了Methanosaeta的相对丰度。优化了酿酒酵母的培养条件,确定了乙醇型发酵预处理的最佳温度和接种比,降低了经济成本。通过乙醇型发酵预处理耦合生物炭,构建了厌氧消化中DIET,强化了厌氧产甲烷,提高了城镇有机固废的资源化和减量化。

Nowadays, the main mechanism of traditional anaerobic digestion relies on interspecific hydro⁃gen transfer (IHT). However, IHT is highly dependent on mass transfer and diffusion rates, which canbe hindered during the treatment of municipal organic solid wastes (MOSW), mainly including foodwaste and waste activated sludge. This hindrance leads to stagnation of methane production. Direct inter⁃specific electron transfer (DIET) has a low dependence on these rates, making it a promising alternativeto IHT for methane production in MOSW anaerobic digestion. Currently, ethanol-type fermentation pre⁃treatment and the addition of carbon-based conductive materials are used to promote DIET. In this study,we used municipal organic solid wastes as the substrate to explore the enhancement of anaerobic methaneproduction performance through ethanol-type fermentation pretreatment coupled with biochar addition.The results showed that: ( 1) Optimal cultivation conditions were achieved for brewing yeast byoptimizing the cultivation time, inoculation ratio, and medium composition. The optimal conditions wereas follows: cultivation time of 21.17 hours, inoculation ratio of 15%, and medium composition per 30 mLliquid medium of 3.00 g glucose, 0.12 g peptone, 0.12 g yeast extract powder, and trace elements.(2) The best process conditions for ethanol - type fermentation pretreatment were determined byoptimizing the temperature and inoculation ratio of brewing yeast. The optimal conditions for ethanol-typefermentation were at temperature of 37 ℃ and a brewing yeast inoculation ratio of 20 mL/ L. (3) A semi-continuous flow anaerobic digestion experiment was designed to investigate the effect of ethanol-type fer⁃mentation pretreatment coupled with biochar on methane production and substrate removal of MOSW.Compared to the control group, the ethanol-type fermentation pretreatment (inoculated with 20 mL/ Lbrewing yeast) coupled with biochar (2 g/ L) group increased methane production by 102.5% and sub⁃strate removal rate by 16.2%. (4) Microbial community analysis revealed that ethanol fermentation pre⁃treatment coupled with biochar increased the relative abundance of Metanosaeta. This study optimized theculture conditions of yeast and determined the optimal pretreatment temperature and inoculation ratio ofethanol fermentation to reduce economic costs. By employing ethanol-type fermentation pretreatment cou⁃pled with biochar addition, DIET was established to enhance methane production and improve the re⁃source utilization and reduction during MOSW anaerobic digestion.

国家重点研发计划青年科学家资助项目(2022YFA0913100);国家自然科学基金面上资助项目(52170125)

王宁,李美,李媛,等.乙醇发酵预处理耦合生物炭强化城镇有机固废厌氧产甲烷[J].能源环境保护,2024,38(5):166-174.

WANG Ning, LI Mei, LI Yuan, et al. Enhancing methane production during anaerobic digestion of municipal or⁃ganic solid wastes by ethanol-type fermentation pretreatment coupled with biochar addition[J]. Energy Environ⁃mental Protection, 2024, 38(5): 166-174.