Microbial Anaerobic Digestion (Bio-Digesters) as an Approach to the Decontamination of Animal Wastes in Pollution Control and the Generation of Renewable Energy

The paper presents the investigations results of the effect of anaerobic digestion on emissions of NH3, N2O and CH4 during storage and after application of slurry. Dairy cattle and pig slurry was stored in concrete tanks (12 m3) over a period of 100 days. Gaseous emissions were collected continuously by a large open dynamic chamber. Gas concentrations (NH3, N2O and CH4) were analysed by high resolution FTIR-spectrometry. After storage, the slurries were surface applied on permanent grassland. NH3 emissions were followed for two days by a large open-dynamic-chamber. N2O and CH4 emissions were quantified with closed chambers until day 20 after application. 65 – 95 % of net total NH3 emissions were lost after slurry application. NH3 abatement will therefore be effective, if low emission application techniques are used. This is especially important when anaerobically digested slurry is applied. More than 90 % of net total CH4 emissions from untreated slurry were lost during slurry storage. Anaerobically digested slurry still emitted methane during storage. These emissions can be totally avoided if the secondary fermentation tank and the slurry store are connected with the gas bearing system of the biogas plant. Then, CH4 produced in these tanks is collected and used as renewable energy source. In conclusion it can be assumed that biogas plants will play a major role in the reduction of greenhouse gas emissions as they generate renewable energy and reduce CH4 emissions during manure storage. Furthermore, anaerobic digestion improves the fertiliser value of animal manures.

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PyADM1: a Python implementation of Anaerobic Digestion Model No. 1

10.1101/2021.03.03.433746 ◽

2021 ◽

Author(s):

Peyman Sadrimajd ◽

Patrick Mannion ◽

Enda Howley ◽

Piet N. L. Lens

Keyword(s):

Machine Learning ◽

Operating System ◽

Mathematical Model ◽

Renewable Energy ◽

Anaerobic Digestion ◽

Waste Treatment ◽

Treatment Technology ◽

Software Implementations ◽

Solid Waste Treatment ◽

Direct Use

Anaerobic Digestion (AD) is a waste treatment technology widely used for wastewater and solid waste treatment, with the advantage of being a source of renewable energy in the form of biogas. Anaerobic digestion model number 1 (ADM1) is the most common mathematical model available for AD modelling. Commercial software implementations of ADM1 are available but have limited flexibility and availability due to the closed sources and licensing fees. Python is the fastest growing programming language and is open source freely available. Python implementation of ADM1 makes this AD model available to the mass user base of the Python ecosystem and it [prime]s libraries. The open easy to use implementation in PyADM1 makes it more accessible and provides possibilities for flexible direct use of the model linked to other software, e.g. machine learning libraries or Linux operating system on embedded hardware.

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Cultured and Uncultured Microbial Community Associated With Biogas Production

10.21203/rs.3.rs-1107386/v1 ◽

2021 ◽

Author(s):

Júlia Ronzella Ottoni ◽

Suzan Prado Fernandes Bernal ◽

Tiago Joelzer Marteres ◽

Franciele Natividade Luiz ◽

Viviane Piccin dos Santos ◽

...

Keyword(s):

Renewable Energy ◽

Microbial Community ◽

Anaerobic Digestion ◽

Biogas Production ◽

Renewable Energy Sources ◽

Starter Culture ◽

Sequencing Analysis ◽

Industrial Plants ◽

Comprehensive Information ◽

Culture Independent

Abstract The search for sustainable development has led countries around the world to seek the improvement of technologies that use renewable energy sources. One of the alternatives in the production of renewable energy comes from the use of waste including urban solids, animal excrement from livestock and biomass residues from agro-industrial plants. These materials may be used in the production of biogas, making its production highly sustainable and environmentally friendly, in addition to reducing public expenses for the treatment of those wastes. The present study evaluated the cultivated and uncultivated microbial community from a substrate (starter) used as an adapter for biogas production in anaerobic digestion processes. 16S rDNA metabarcoding revealed domain of bacteria belonging to the phyla Firmicutes, Bacteroidota, Chloroflexi and Synergistota. The methanogenic group was represented by the phyla Halobacterota and Euryarchaeota. Through 16S rRNA sequencing analysis of isolates recovered from the starter culture, the genera Rhodococcus, Vagococcus, Lysinibacillus, Niallia, Priestia, Robertmurraya, Luteimonas and Proteiniclasticum were recovered, groups that were not observed in the metabarcoding data. The groups mentioned are involved in the metabolism pathways of sugars and other compounds derived from lignocellulosic material, as well as in anaerobic methane production processes. The results demonstrate that culture-dependent approaches, such as isolation and sequencing of isolates, as well as culture-independent studies, such as the Metabarcoding approach, are complementary methodologies that, when integrated, provide robust and comprehensive information about the microbial communities involved in various processes, including the production of biogas in anaerobic digestion processes.

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