廃下水汚泥を使用したリグノセルロース系バイオマスの嫌気性消化を改善するための微生物機能の最適化

• Material Type: 博士論文
• Title: 廃下水汚泥を使用したリグノセルロース系バイオマスの嫌気性消化を改善するための微生物機能の最適化
• Author/Editor: Zhu, Qili
• Author Heading: Zhu, Qili
• Publication Date: 2022-12-27
• Publication Date (W3CDTF): 2022-12-27
• Alternative Title: Optimization of Microbial Functions to Improve Anaerobic Digestion of Lignocellulosic Biomass using Waste Sewage Sludge
• Degree Grantor: 九州工業大学
• Date Granted: 2022-12-27
• Date Granted (W3CDTF): 2022-12-27
• Dissertation Number: 甲第453号
• Degree Type: 博士（工学）
• Text Language Code: eng
• Subject Heading: Lignocellulosic biomass; Waste sewage sludge; Anaerobic digestion; Antibiotics; Microbial communities
• Target Audience: 一般
• Note (General): 九州工業大学博士学位論文 学位記番号：生工博甲第453号 学位授与年月日：令和4年12月27日; 令和4年度
• DOI: 10.18997/0002000326; https://doi.org/10.18997/0002000326
• Persistent ID (NDL): info:ndljp/pid/13235612; https://dl.ndl.go.jp/pid/13235612
• Collection: 障害者向け資料
• Collection (Materials For Handicapped People:1): テキストデータ
• Collection (particular): 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文; https://dl.ndl.go.jp/collections/A00014
• Acquisition Basis: 博士論文（自動収集）
• Date Accepted (W3CDTF): 2024-01-19T16:23:17+09:00
• Format (IMT): application/pdf
• Access Restrictions: 国立国会図書館内限定公開
• Service for the Digitized Contents Transmission Service: 図書館・個人送信対象外
• Availability of remote photoduplication service: 可
• Periodical Title (URI): https://doi.org/10.18997/0002000326; http://hdl.handle.net/10228/0002000326
• Data Provider (Database): 国立国会図書館 : 国立国会図書館デジタルコレクション; https://dl.ndl.go.jp

• Summary, etc.: Energy crisis and environmental pollution has provided impetus for increasing development of renewable energy from lignocellulosic wastes in recent years. Anaerobic digestion (AD) has been regarded as a useful method for converting organic resources to renewable energy like hydrogen (H2), methane (CH4). As one of the main lignocellulosic biomasses, crop stalks are promising feedstocks for AD process due to their plentiful supply and low costs. However, low CH4 production is the main bottleneck for its energy utilization. One of main reasons for the low CH4 production from crop stalks is attributed to the lack of nitrogen source due to the high carbon/nitrogen (C/N) ratio containing in crop stalks. On the contrary, waste sewage sludge (WSS) is sufficient in nitrogen source due to its lower C/N ratio. Meanwhile, it is well-known that WSS is also enriched with various microorganisms, which can assist in degrading the organic materials. Microbial communities, especially functional microorganisms are reported to be closely correlated with CH4 production during AD process. Taken together, WSS was used as inoculum for AD of lignocellulosic biomass in this study. Actually, in addition to being rich in nitrogen resource and microorganisms, there are also various kinds of antibiotics containing in WSS, which may change the microbial activity and further to influence the AD process. Different effects including promotion, no significant impact and inhibition on AD process have been reported in some researches. But most of substrates used in these researches are sludges or manures. Less information about the effects of antibiotics on AD of lignocellulosic biomass is reported. Therefore, the aims of this study mainly include: 1) to evaluate the impact of enrichment of WSS on the AD of cellulose; 2) to investigate the effects of different antibiotics on the AD process of cellulose inoculated with initial WSS or enriched WSS; 3) to study the application of antibiotics on the bio-gasification of crop stalk. Enrichment of WSS was investigated in this study to obtain higher abundance of cellulolytic bacteria and further to enhance CH4 yield from AD of cellulose. Results of this study demonstrated that the AD of cellulose inoculated with enriched sludge without carboxymethylcellulose (CMC) addition displayed higher CH4 yield and greater anaerobic biodegradation of cellulose compared with control. Enrichment of WSS promoted AD of cellulose at hydrolytic, acidogenic, acetogenic, and methanogenic processes during the fermentation. Notably, Ruminiclostridium and Methanobacterium were found to be the predominant genera in AD of cellulose inoculated with enriched sludge without CMC addition. The comparative effects of several widely used antibiotics (tetracycline (TC), azithromycin (AZM) and cephalexin (CLX), belong to tetracyclines, macrolides and cephalosporins, respectively.) on CH4 production from cellulose inoculated with initial sludge (IS) and enriched sludge (ES) were investigated respectively in this study. The results showed that the addition of AZM displayed more positive effect on CH4 yield from cellulose inoculated with IS compared with TC. The addition of AZM and TC both represented no significant effect on AD of cellulose inoculated with ES. Specifically, AZM addition stimulated the AD of cellulose inoculated with IS at all stages including hydrolysis, acidogenesis/acetogenesis and methanogenesis while TC addition promoted it mainly at methanogenesis stage. Notably, the addition of AZM increased the RA of bacterial phylum Firmicutes, Bacteroidetes, Fibrobacteres and archaeal genera Methanosaeta, Methanosarcina, which were considered as contributors for AD of cellulose inoculated with IS. On the contrary, the addition of CLX displayed inhibitory effect on CH4 yield from cellulose regardless of being inoculated with IS or ES. The application of effective antibiotics including TC and AZM on AD of corn straw inoculated with IS was also studied to evaluate the influences of TC and AZM on CH4 production from crop stalk in this study. As a result, about 65.22% and 25.38% enhanced CH4 yield were observed in AZM and TC compared with control during 20 days’ fermentation, respectively. Specifically, AZM promoted CH4 yield at all stages including hydrolysis, acidogenesis/acetogenesis and methanogenesis while TC enhanced CH4 yield mainly at acidogenesis/acetogenesis and methanogenesis stages. Bacterial phylum Bacteroidetes, Actinobacteria and archaeal genera Methanosarcina, Methanobrevibacter were considered as functional microorganisms for AD of CS under AZM addition. Future work should be focused on seeking for other antibiotics which play positive effects on AD of lignocellulosic biomass inoculated with enriched sludge. In addition, pilot experiment and engineering application research of this new technology need to be considered. Such work can provide new approach for more efficient energy utilization of lignocellulosic biomass and further to alleviate current environmental pollution and energy crisis, especially in the current case of advocating low carbon society.
• DOI: 10.18997/0002000326; https://doi.org/10.18997/0002000326
• Format (IMT): application/pdf
• Source: fulltext; https://kyutech.repo.nii.ac.jp/record/2000326/files/sei_k_453.pdf
• Access Restrictions: インターネット公開
• Data Provider (Database): 国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）; https://irdb.nii.ac.jp
• Original Data Provider (Database): 九州工業大学 : キューテイカー

Table of Contents

1. Introduction||2. Impact of enrichment of waste sewage sludge on methane production from cellulose||3. Effects of different antibiotics on anaerobic digestion of cellulose inoculated with waste sewage sludge||4. Application of antibiotics on the bio-gasification of corn straw||5. Conclusions and suggestions for further research