混合添加生物炭和Fe_(3)O_(4)的青稞秸秆厌氧消化产甲烷工艺及微生物功能优化  

Optimization of anaerobic digestion process for methane production and microbial functions of hulless barley straw with mixed addition of biochar and Fe_(3)O_(4)

作　　者：张智伟 刘海林 李屹[1] 杜中平 韩睿[1] ZHANG Zhiwei;LIU Hailin;LI Yi;DU Zhongping;HAN Rui(Qinghai Key Laboratory of Vegetable Genetics and Physiology,Academy of Agriculture and Forestry Sciences,Qinghai University,Xining,Qinghai,China;Science and Technology Department,Qinghai University,Xining,Qinghai,China)

机构地区：[1]青海大学农林科学院,青海省蔬菜遗传与生理重点实验室,青海西宁 [2]青海大学科技处,青海西宁

出　　处：《微生物学报》2025年第4期1742-1757,共16页Acta Microbiologica Sinica

基　　金：青海省应用基础研究计划(2024-ZJ-778)。

摘　　要：【目的】明确混合添加生物炭和Fe_(3)O_(4)介导的青稞秸秆厌氧消化产甲烷的最优工艺参数,并探究混合添加生物炭和Fe_(3)O_(4)在木质纤维素类废弃物厌氧消化应用中的可行性。【方法】以青稞秸秆为原料,通过单因素试验和响应面法对混合添加生物炭和Fe_(3)O_(4)介导的青稞秸秆厌氧消化产甲烷工艺进行优化。利用宏基因组技术分析消化过程中的微生物群落结构和甲烷代谢途径。【结果】经响应面模型验证试验得到最优工艺条件为:总固体含量6.32%、生物炭与Fe_(3)O_(4)混合比6.83:3.17、接种比(接种污泥与青稞秸秆挥发性固体量的比值)2.51。在该条件下,基于挥发性固体计算的累积甲烷产量实测值为269.04 mL/g,与预测值(265.95 mL/g)的相对误差小于5%,验证了模型的有效性。该优化条件下的混合添加处理能显著提高青稞秸秆的产甲烷能力(P<0.05),效果与化学预处理相当,同时提升了乙酸含量,并减少了丙酸和丁酸的积累。宏基因组分析显示,拟杆菌门未分类属(unclassified_Bacteroidota)、未分类细菌(unclassified_Bacteria)、梭菌属(Clostridium)、丝状杆菌属(Fibrobacter)等细菌类群,以及甲烷八叠球菌属(Methanosarcina)、甲烷丝菌属(Methanothrix)等乙酸营养型产甲烷菌的相对丰度增加,促进了乙酸的利用并强化了微生物间的种间直接电子传递(direct interspecies electron transfer,DIET)。甲烷代谢途径分析表明,混合添加生物炭和Fe_(3)O_(4)的消化系统强化了乙酸营养型产甲烷途径,从而提升了甲烷产量。【结论】响应面法能较好地优化混合添加生物炭和Fe_(3)O_(4)介导的青稞秸秆厌氧消化产甲烷工艺。混合添加生物炭和Fe_(3)O_(4)是一种高效且环境友好的木质纤维素类废弃物处理方法,有助于提升生物甲烷的产量。[Objective]To optimize the anaerobic digestion process for methane production of hulless barley straw with mixed addition of biochar and Fe_(3)O_(4)and investigate the feasibility of mixed addition of biochar and Fe_(3)O_(4)in the anaerobic digestion of lignocellulosic waste.[Methods]We employed single factor and response surface experiments to optimize the anaerobic digestion process for methane production of hulless barley straw with mixed addition of biochar and Fe_(3)O_(4).Metagenomics was employed to analyze the microbial community structure and methane production pathway during digestion.[Results]The optimal digestion conditions were 6.32%total solids,biochar-to-Fe_(3)O_(4)ratio of 6.83:3.17,and inoculation ratio(volatile solids ratio of inoculum to hulless barley straw)of 2.51.Under these conditions,the measured value of cumulative methane production based on volatile solids was 269.04 mL/g,with a relative error of less than 5%from the predicted value(265.95 mL/g),which indicated that the model was effective.The mixed addition treatment under the optimized conditions increased the methane production of hulless barley straw(P<0.05),with the effect comparable to that of the chemical pre-treatment.Meanwhile,the treatment increased the acetic acid content while reducing the accumulation of propionic and butyric acids.Metagenomic analysis showed increases in the relative abundance of bacterial taxa such as unclassified_Bacteroidota,unclassified_Bacteria,Clostridium,and Fibrobacter,as well as acetotrophic methanogens such as Methanosarcina and Methanothrix,which promoted the utilization of acetic acid and enhanced the direct interspecies electron transfer(DIET)between microorganisms.The mixed addition of biochar and Fe_(3)O_(4)in the anaerobic digestion system enhanced the acetotrophic methanogenic pathway,thereby enhancing methane production.[Conclusion]The response surface methodology can optimize the anaerobic digestion process for methane production of hulless barley straw with mixed addition of biochar and

关 键 词：青稞秸秆 厌氧消化 生物炭 FE3O4 响应面法 宏基因组 微生物群落 甲烷代谢途径 

分 类 号：S216.2[农业科学—农业机械化工程]