Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2023
Abstract
The anaerobic digestion of organic materials produces biogas; however, optimizing methane (CH4) content within biogas plants by capturing carbon dioxide (CO2) is one of the challenges for sustainable biomethane production. CH4 is separated from biogas, which is called biogas upgrading for biomethane production. In this regard, in-situ CO2 capture and utilization could be an alternative approach that can be achieved using conductive particles, where the conductive particles support the direct intraspecific electron transfer (DIET) to promote CH4 production. In this investigation, a carbon nanotube (CNT) was grown over conductive activated carbon (AC). Then an iron (Fe) nanoparticle was anchored (AC/CNT/Fe), which ultimately supported microbes to build the biofilm matrix, thereby enhancing the DIET for CH4 formation. The biogas production and CH4 content increased by 17.57 % and 15.91 %, respectively, when AC/CNT/Fe was utilized. Additionally, 18S rRNA gene sequencing reveals that Methanosarcinaceae and Methanobacteriaceae families were the most dominant microbes in the reactor when conductive particles (AC/CNT/Fe) were applied. The proposed study supports the stable operation of biogas plants to utilize CO2 for CH4 production by using surface-modified material.
Abstract
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Authors
Yi Zhang Yijing Feng Zhonghao Ren Runguo Zuo Tianhui Zhang Yeqing Li Yajing Wang Zhiyang Liu Ziyan Sun Yongming Han Lu Feng Mortaza Aghbashlo Meisam Tabatabaei Junting PanAbstract
The ideal conditions for anaerobic digestion experiments with biochar addition are challenging to thoroughly study due to different experimental purposes. Therefore, three tree-based machine learning models were developed to depict the intricate connection between biochar properties and anaerobic digestion. For the methane yield and maximum methane production rate, the gradient boosting decision tree produced R2 values of 0.84 and 0.69, respectively. According to feature analysis, digestion time and particle size had a substantial impact on the methane yield and production rate, respectively. When particle sizes were in the range of 0.3–0.5 mm and the specific surface area was approximately 290 m2/g, corresponding to a range of O content (>31%) and biochar addition (>20 g/L), the maximum promotion of methane yield and maximum methane production rate were attained. Therefore, this study presents new insights into the effects of biochar on anaerobic digestion through tree-based machine learning.
Authors
Yi Zhang Zhangmu Jing Yijing Feng Shuo Chen Yeqing Li Yongming Han Lu Feng Junting Pan Mahmoud Mazarji Hongjun Zhou Xiaonan Wang Chunming XuAbstract
Exploring key factors has important guidance for understanding complex anaerobic digestion (AD) systems. This study proposed a multi-layer automated machine learning framework to understand the complex interactions in AD systems and explore key factors at the environmental factor, microorganisms and system levels. The first layer of the framework identified hydraulic residence time (HRT) as the most important environmental factor, with an optimal range of 33–45 d. In the second layer of the framework, Methanocelleus (optimal relative abundance (ORA) = 3.0%) and Candidatus_Caldatribacterium (ORA = 1.7%) were found to be the key archaea and bacteria, respectively. Furthermore, the prediction of key microorganisms based on environmental factors and remaining microbial data showed the essential roles of Methanothermobacter and Acetomicrobium. The third layer for finding the optimal combination of data variables for predicting biogas production demonstrated that combined Archaea genera and environmental factors should be achieved for the most accurate prediction (root mean square error (RMSE) = 84.21). GBM had the best model performance and prediction accuracy among all the built-in models. Based on the optimal GBM model, the analysis at the system level showed that HRT was the most important variable. However the most important microorganism, Methanocelleus, within the appropriate survival range is also essential to achieve optimal biogas production. This research explores key parameters at various levels through automated machine learning techniques, which are expected to provide guidance in understanding the complex architecture of industrial and laboratory AD systems.
Abstract
利用可再生能源发电获得单细胞蛋白质，即“电转蛋白质（Power-to-Protein，PtP）”，是生产单细胞蛋白质的 绿色可持续途径. 厌氧消化（anaerobic digestion，AD）可提供“电转蛋白质”过程中所需要的碳源以及部分氮源、微 量元素等，通过厌氧消化与“电转蛋白质”技术相结合构建了一种可持续的蛋白质生产工艺，“厌氧消化-电转蛋白质 （anaerobic digestion-Power-to-Protein，ADPtP）”. 本文介绍现有利用AD出料培养微生物获得单细胞蛋白质的工艺， 分析引入PtP技术后的工艺效率与能耗，重点介绍ADPtP工艺的基础模式、过程中资源整合与利用. 在电化学法还原模 式中将沼气升级后培养甲烷氧化细菌操作简便易行且环境效益高，而以Wood-Ljungdahl碳转化途径设计的ADPtP工艺 在安全性方面占优势. ADPtP工艺中，降低爆炸风险和提高转化效率是亟须解决的关键问题. 另外，工艺中资源整合方 式为电化学沼气升级、电化学消化液提氨、电解水产氢. 未来，我国沼气产量与潜在储备量以及可再生能源发电量将为 ADPtP提供发展基础，同时具有良好的政策环境和巨大的潜在蛋白质市场需求，因此该工艺在我国作为新型绿色蛋白质 生产工艺而施行具有良好基础与应用前景. （图1 表2 参64）
Authors
Claire CoutrisAbstract
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Authors
Claire CoutrisAbstract
Det er ikke registrert sammendrag
Abstract
NIBIO, NORSUS og Norwaste har vært involvert i et forskningsprosjekt finansiert av Handelens Miljøfond, som har tatt for seg bionedbrytbar plast og innsamlingsløsninger for matavfall i Norge. Forskerne fant at bionedbrytbar plast i svært liten grad brytes ned i biogassprosessen. Prosjektet pågikk fra juni 2022, sluttrapporten ble levert i august i år. NIBIO valgte de to mest brukte bionedbrytbare plastposene i Norge, og kjørte laboratorieforsøk der man så på nedbrytningen av disse under anaerob utråtning (biogassprosessen). Det ble først gjort forbehandling med termisk hydrolyse, og siden forsøk under såkalt termofile og mesofile forhold, altså med varmebehandling. – Vi hadde en ganske lang oppholdstid på 22 dager. Det store spørsmålet var om disse posene brytes ned under slike forhold. Det korte svaret er at det skjer i svært liten grad, sier NIBIO-forsker Claire Coutris til Biogassbransjen.no. Posene merket «hjemmekomposterbare» tapte maksimalt 33 prosent av opprinnelig vekt under termofile forhold, 55 grader. De som var markert «komposterbare i industriell kompostering» hadde et vekttap på 14-21 prosent. – Posene er nedbrytbare, men ikke under anaerob utråtning, sier Coutris. – Ved kompostering ved cirka 60 grader skal de bli borte i løpet av 6 måneder. Komposteringsprosesser foregår over mye lenger tid enn prosesser i biogassanlegg. Det var 4 prosent plast i matavfallet, som tilsvarer det man finner i faktisk produksjon, forteller Coutris. – Sannsynligvis vil det være behov for etterbehandling av biorest selv når matavfallet samles inn i bionedbrytbare poser. – Men vil det være noe problem å kjøre bioresten på jordet med bionedbrytbar plast, hvis den uansett brytes ned på sikt? – Disse posene er nedbrytbare under spesifikke forhold. Industriell kompost holder minst 60 grader i minst 4 uker. Jord holder sjelden mer enn 20 grader, og vi kan dermed ikke forvente at plasten brytes ned fort nok til at den ikke vil akkumuleres i jord. Coutris ser for seg videre forsøk hvor man kan bruke plastbitene fra forsøker i landbruksjord for å se hvor raskt de brytes ned under slike forhold.
Authors
Claire CoutrisAbstract
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Authors
Claire CoutrisAbstract
Det er ikke registrert sammendrag