生物炭强化废弃生物质降解产氢及其机理研究

High value utilization of waste biomass has always been a research hotspot of solid waste reclamation. Previous studies have found that C. thermocellum can effectively improve the anaerobic digestion and hydrogen production efficiency of papermaking sludge, and the effect is expected to be further improved by bio-char. Therefore, this project aims at improving waste biomass degradation efficiency and hydrogen production by immobilizing C. thermocellum with bio-char, and further shedding light its mechanism. In the present project, immobilized C. thermocellum was built with bio-char firstly, and verified the intensifying effect of bio-char on hydrogen production taking paper sludge as an example. Concomitantly, the adsorption and pH buffering effect, as well as the electron transfer promotion of bio-char were analyzed during biohydrogen production. Finally, FI-RP and Py-GC/MS technologies were combined to reveal the evolution rules of organic components within/out bio-char intervention, and high-throughput sequencing and bioinformatics technologies were employed to unveil the succession of microbial community in the biodegradation system enhanced by C.thermocellum and bio-char in terms of metabolic function and electron transfer function. The research results will enrich the academic connotation involved in improved solid waste reclamation with bio-char, promote the recycle and utilization of waste biomass, and drive the green development of clean and renewable energy industry.

废弃生物质的高值化利用一直以来是固废资源化利用的研究热点。前期研究发现，嗜热厌氧梭菌C.thermocellum能有效提高造纸污泥产氢发酵的效率，而生物炭可使该效应进一步提高。因此，本项目拟以强化废弃生物质降解产氢为目的，深入研究生物炭对C.thermocellum的固定化作用及其强化废弃生物质降解产氢的机理。项目以造纸污泥为例，利用生物炭对C.thermocellum进行固定化，验证生物炭对废弃生物质降解及产氢的增效作用，分别解析生物炭的固定吸附、pH缓冲及强化电子传递作用对产氢的贡献；借助FI-RP和Py-GC/MS技术解析生物炭介入前后废弃生物质组分的演化规律，利用高通量测序和生物信息学技术分析嗜热厌氧梭菌和生物炭强化体系中微生物群落在代谢和电子传递功能上的演替规律。项目的实施可以丰富生物炭在固废资源化利用的理论基础，促进废弃生物质的资源化利用，推动清洁能源产业的绿色发展。

废弃生物质的高值化利用一直是固废资源化利用的研究热点。本项目以造纸污泥为废弃生物质的代表，探索生物炭增促Clostridium thermocellum降解废弃生物质产氢的强化作用机制。项目首先探索了生物炭对 Clostridium thermocellum 的固定化、污泥的降解及发酵产氢的规律；接着尝试对生物炭的电子传递机制在强化产氢发酵中的贡献机制做出解析，最后分析生物炭对生物降解体系中微生物电子传递的增效作用及其引发的微生物种群结构演替规律。.结果发现，不同材料来源、不同条件制备的生物炭在自身物化特性上具有显著的差异，制备的生物炭对暗发酵产氢效率与微生物生长代谢表现出截然不同的影响。制备温度越高，生物炭的成炭率越低，而表面碱度、电导率及比表面积普遍呈上升趋势。添加生物炭显著改善了Clostridium thermocellum MJC1 利用预处理的甘蔗渣（PSCB）降解产氢性能。其中，添加甘蔗渣生物炭和菇渣生物炭（700 ℃, SMC7）使Clostridium thermocellum发酵纤维二糖的产氢量分别提高了41%和94%，SMC7使Clostridium thermocellum发酵HPAC-SCB的产氢量和底物降解率分别提高37%和10%。.生物炭可降低微生物胞外电活性介质的分泌，不同生物炭在微生物演替、优势微生物组成和丰度以及底物利用偏好等方面有显著差异。生物炭能够显著提高胞内外还原力水平、提高生物量、改善关键酶活力、刺激胞外聚合物的合成、改善发酵体系电子传递效率和功能菌的丰度，并且显著提高最大产氢速率和产氢潜力，分别提高5.8倍和3.0倍，所形成的微生物空间群落结构可能有助于优势种之间的协同降解产氢作用。.生物炭在发酵初始迅速构建起针对底物进行有效降解利用的微生物群落，在后续发酵过程中几乎不发生演替；生物炭的添加显著富集了一些具有重要功能微生物的丰度，细菌方面，最显著的是发酵单胞菌，长线菌、甲烷八叠球菌；生物炭起到了同时作为细胞载体和电子传递载体的作用，成功构建起了更加高效的底物转化和产甲烷生态位，可能对于改善电子传递效率和群落间微生物互营代谢具有重要意义。.上述研究可为实现废弃生物质的高效降解及产氢的产业化发展提供技术储备和理论依据。