Anaerobic digestion of raw sludge within mesophilic and thermophilic temperatures
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB60745 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Anaerobic digestion (AnD) is a microbiological process that converts organic waste materials into biogas. Because of its high methane content, biogas is a combustible energy source and serves as an important environmental technology commonly used in the management of animal waste generated on large animal farms. Much work has been done on hardware design and process engineering for the generation of biogas. However, little is known about the complexity of the microbiology in this process. In particular, how microbes interact in the digester and eventually breakdown and convert organic matter into biogas is still regarded as a "black box." We used 16S rRNA sequencing as a tool to study the microbial community in laboratory hog waste digesters under tightly controlled conditions, and systematically unraveled the distinct interaction networks of two microbial communities from mesophilic (MAnD) and thermophilic anaerobic digestion (TAnD). Under thermophilic conditions, the well-known association between hydrogen-producing bacteria, e.g., Ruminococcaceae and Prevotellaceae, and hydrotrophic methanogens, Methanomicrobiaceae, was reverse engineered by their interactive topological niches. The inferred interaction network provides a sketch enabling the determination of microbial interactive relationships that conventional strategy of finding differential taxa was hard to achieve. This research is still in its infancy, but it can help to depict the dynamics of microbial ecosystems and to lay the groundwork for understanding how microorganisms cohabit in the anaerobic digester.
| S-EPMC5521784 | biostudies-literature
Project description:Mesophilic and thermophilic anaerobic digestion bioreactors Raw sequence reads
| PRJNA1185473 | ENA
Project description:In this study, productivity and physicochemical and microbiological (454 sequencing) parameters, as well as environmental criteria, were investigated in anaerobic reactors to contribute to the ongoing debate about the optimal temperature range for treating animal manure, and expand the general knowledge on the relation between microbiological and physicochemical process indicators. For this purpose, two reactor sizes were used (10 m(3) and 16 l), in which two temperature conditions (35°C and 50°C) were tested. In addition, the effect of the hydraulic retention time was evaluated (16 versus 20 days). Thermophilic anaerobic digestion showed higher organic matter degradation (especially fiber), higher pH and higher methane (CH₄) yield, as well as better percentage of ultimate CH₄ yield retrieved and lower residual CH₄ emission, when compared with mesophilic conditions. In addition, lower microbial diversity was found in the thermophilic reactors, especially for Bacteria, where a clear intensification towards Clostridia class members was evident. Independent of temperature, some similarities were found in digestates when comparing with animal manure, including low volatile fatty acids concentrations and a high fraction of Euryarchaeota in the total microbial community, in which members of Methanosarcinales dominated for both temperature conditions; these indicators could be considered a sign of process stability.
| S-EPMC4554467 | biostudies-literature
Project description:BackgroundSubstrate spectra for anaerobic digestion have been broadened in the past decade, inter alia, due to the application of different pretreatment strategies and now include materials rich in lignocellulose, protein, and/or fat. The application of these substrates, however, also entails risks regarding the formation of undesired by-products, among which phenolic compounds are known to accumulate under unfavorable digestion conditions.MethodsDifferent states of overload were simulated in batch experiments while reviewing the generation of phenyl acids out of different lab-use substrates in order to evaluate the impact on biogas and methane production as well as some additional process performance parameters under defined laboratory conditions. Investigations were conducted under both mesophilic and thermophilic conditions.ResultsIt could be shown that the tested input materials led to the formation of phenyl acids in a substrate-dependent manner with the formation itself being less temperature driven. Once formed, the formation of phenyl acids turned out to be a reversible process.ConclusionsAlthough a mandatory negative impact of phenyl acids per se on the anaerobic digestion process in general and the methanogenesis process in particular could not be proven, phenyl acids, however, seem to play an important role in the microbial response to overloaded biogas systems.
| S-EPMC6368962 | biostudies-literature
Project description:Since the COVID-19 outbreak has started in late 2019, SARS-CoV-2 has been widely detected in human stools and in urban wastewater. No infectious SARS-CoV-2 particles have been detected in raw wastewater until now, but it has been reported occasionally in human stools. This has raised questions on the fate of SARS-CoV-2 during wastewater treatment and notably in its end-product, wastewater treatment sludge, which is classically valorized by land spreading for agricultural amendment. In the present work, we focused on SARS-CoV-2 stability in wastewater treatment sludge, either during storage (4 °C, room temperature) or thermophilic anaerobic digestion (50 °C). Anaerobic digestion is one of the possible processes for sludge valorization. Experiments were conducted in laboratory pilots; SARS-CoV-2 detection was based on RT-quantitative PCR or RT-digital droplet PCR. In addition to SARS-CoV-2, Bovine Coronavirus (BCoV) particles were used as surrogate virus. The RNA from SARS-CoV-2 particles, inactivated or not, was close to the detection limit but stable in wastewater treatment sludge, over the whole duration of the assays at 4 °C (55 days) and at ambient temperature (∼20 °C, 25 days). By contrast, the RNA levels of BCoV and inactivated SARS-CoV-2 particles decreased rapidly during the thermophilic anaerobic digestion of wastewater treatment sludge lasting for 5 days, with final levels that were close to the detection limit. Although the particles' infectivity was not assessed, these results suggest that thermophilic anaerobic digestion is a suitable process for sludge sanitation, consistent with previous knowledge on other coronaviruses.
| S-EPMC9391084 | biostudies-literature
Project description:Viruses represent major disease transmitting agents carried by human excreta and animal manure. Understanding virus inactivation is therefore essential in preventing microbial spread due to inadequate treatment of these materials. Here, we investigated the inactivation kinetics of the single-stranded (ss) RNA phage MS2, DNA phages T4 and ?X174, andthe double-stranded DNA human adenovirus in stored human urine, sludge, and animal manure, at temperatures and pH valuestypical of storage under naturally occurring conditions or mesophilic anaerobic digestion (<40 °C). The ssRNA phage MS2 was most readily inactivated in all samples compared to the other viruses tested. This is consistent with previous findings in wellcontrolled buffer solutions of similar composition, where inactivation was found to be governedby bases (NH3, carbonate, hydroxide) that catalyze the transesterification and cleavage of the ssRNA. Correspondingly, MS2 inactivation kinetics in real matrices could be adequately modelled by only taking into account the effects of temperature, pH, carbonate and ammonia on the integrity of ssRNA. DNA viruses were more persistent compared to MS2;however, inactivation in selected sludge and manure samples proceeded at faster rates compared to well-controlled buffersolutions of similar composition. This indicates a contribution of microbial or enzymatic activity to inactivation of DNA viruses. Overall, this study identifies the most important factors contributing to inactivation of viruses in human excreta and manure, and highlights the differences in inactivation kinetics and mechanisms between ssRNA and DNA viruses.
| S-EPMC7705124 | biostudies-literature
Project description: Not available
| S-EPMC10616142 | biostudies-literature
Project description:Mesophilic anaerobic digestion reactor Raw sequence reads
| PRJNA1085251 | ENA
Project description:Anaerobic digestion sludge raw sequence reads Raw sequence reads
| PRJNA895873 | ENA
Project description:Anaerobic digestion sludge raw sequence reads
| PRJNA891909 | ENA