Search results for "bioga"
showing 10 items of 163 documents
Influence of food waste addition over microbial communities in an Anaerobic Membrane Bioreactor plant treating urban wastewater
2018
[EN] Notorious changes in microbial communities were observed during and after the joint treatment of wastewater with Food Waste (FW) in an Anaerobic Membrane Bioreactor (AnMBR) plant. The microbial population was analysed by high-throughput sequencing of the 16S rRNA gene and dominance of Chloroflexi, Firmicutes, Synergistetes and Proteobacteria phyla was found. The relative abundance of these potential hydrolytic phyla increased as a higher fraction of FW was jointly treated. Moreover, whereas Specific Methanogenic Activity (SMA) rose from 10 to 51 mL CH4 g(-1) VS, Methanosarcinales order increased from 34.0% over 80.0% of total Archaea, being Methanosaeta the dominant genus. The effect o…
Methane oxidation in industrial biogas plants-Insights in a novel methanotrophic environment evidenced by pmoA gene analyses and stable isotope label…
2018
Abstract A broad methanotrophic community consisting of 16 different operational taxonomic units (OTUs) was detected by particulate methane monooxygenase A (pmoA) gene analyses of reactor sludge samples obtained from an industrial biogas plant. Using a cloning-sequencing approach, 75% of the OTUs were affiliated to the group of type I methanotrophs (γ-Proteobacteria) and 25% to type II methanotrophs (α-Proteobacteria) with a distinct predominance of the genus Methylobacter. By database matching, half of the total OTUs may constitute entirely novel species. For evaluation of process conditions that support growth of methanotrophic bacteria, qPCR analyses of pmoA gene copy numbers were perfor…
Renewable energies, business models and local growth
2018
Abstract Energy is one of the driving factors of the world economy: energy consumption is closely linked to quality of life and environmental impact. Reducing the use of fossil fuels, curtailing greenhouse gas emissions, and cutting energy dependence from traditional energy producing countries are the cornerstones of European policies for safe, competitive, sustainable, and renewable energy. In addition, the pressing need to provide new and diversified opportunities for supplementary income for the agricultural sector has fueled the desire to engage rural areas in this process. Biogas, derived from the anaerobic digestion of biomass, is one of the renewable energy sources that has been very…
Isolation of lactic acid-forming bacteria from biogas plants.
2017
Direct molecular approaches provide hints that lactic acid bacteria play an important role in the degradation process of organic material to methanogenetic substrates in biogas plants. However, their diversity in biogas fermenter samples has not been analyzed in detail yet. For that reason, five different biogas fermenters, which were fed mainly with maize silage and manure from cattle or pigs, were examined for the occurrence of lactic acid-forming bacteria. A total of 197 lactic acid-forming bacterial strains were isolated, which we assigned to 21 species, belonging to the genera Bacillus, Clostridium, Lactobacillus, Pediococcus, Streptococcus and Pseudoramibacter-related. A qualitative m…
Insights into the biological process performance and microbial diversity during thermophilic microalgae co-digestion in an anaerobic membrane bioreac…
2020
Abstract Harvested microalgae Chlorella spp. and primary sludge were co-digested in a laboratory-scale anaerobic membrane bioreactor (AnMBR) under thermophilic conditions (55 °C). The system was run for 700 days divided into four experimental phases to determine the influence of the organic loading rate on the process performance and the microbial community. The rise in organic loading rate from 0.17 to 0.5 gCOD·L−1·d−1 led to a 35% improvement in methane production. The system reached 69% biodegradability working at 0.5 gCOD·L−1·d−1 and a high solids retention time (70 d), indicating the efficient conversion of biomass into biogas through the AnMBR configuration while avoiding possible inh…
Landfill gas upgrading with pilot-scale water scrubber: Performance assessment with absorption water recycling
2012
Abstract A pilot-scale counter current absorption process for upgrading municipal solid waste (MSW) landfill gas to produce vehicle fuel was studied using absorption, desorption and drying units and water as an absorbent. Continuous water recycling was used without adding new water to the system. The process parameters were defined by a previous study made with this pilot system. The effect of pressure (20–25 bar), temperature (10–25 °C) and water flow speed (5.5–11 l/min) on the upgrading performance, trace compounds (siloxanes, halogenated compounds) and water quality were investigated. Raw landfill gas flow was kept constant at 7.41 Nm3/h. Methane (CH4) and carbon dioxide (CO2) contents …
Complete genome sequence of the strain Defluviitoga tunisiensis L3, isolated from a thermophilic, production-scale biogas plant.
2015
An anaerobic, thermophilic bacterium belonging to the phylum Thermotogae was isolated from a rural, thermophilic biogas plant (54 degrees C) producing methane-rich biogas from maize silage, barley, cattle and pig manure. Here we report the first complete genome sequence of the Defluviitoga tunisiensis strain L3, an isolate from the family Thermotogaceae. The strain L3 encodes several genes predicted to be involved in utilization of a large diversity of complex carbohydrates including cellobiose and xylan for the production of acetate, hydrogen (H-2) and carbon dioxide (CO2). The genome sequence of D. tunisiensis L3 provides the basis for biotechnological exploitation of genetic determinants…
Current state and future of biogas and digestate production
2013
Over the past few years, the worldwide cost of energy has increased significantly, due to a growing global demand for energy and the decreasing availability of fossil fuel sources. Many countries are adopting environmental policies promoting the production and consumption of alternative, sustainable and renewable energy sources. Among these sources is green energy production through the anaerobic digestion of agricultural feedstock, like animal manure and food industry by-products, mainly aimed at producing biogas. Nevertheless, only a very small part of the biogas potential is currently used, while many European countries are facing huge problems caused by the overproduction of organic was…
Aspen Plus process-simulation model: Producing biogas from VOC emissions in an anaerobic bioscrubber
2018
A process-simulation model for a novel process consisted of an anaerobic bioscrubber was developed in Aspen Plus®. A novel approach was performed to implement the anaerobic reactor in the simulation, enabling it to be connected to the scrubber. The model was calibrated and validated using data from an industrial prototype that converted air emissions polluted with volatile organic compounds with an average daily concentration of 1129 mgC Nm−3 into bioenergy for more than one year. The scrubber, which showed a removal efficiency within 83-93%, was successfully predicted with an average absolute relative error of 5.2 ± 0.08% using an average height-to-theoretical-plate value of 1.05 ± 0.08 m …
Effect of substrate improvement on optimising biogas yield from anaerobic digestion
2014
Masteroppgave i fornybar energi ENE 500 Universitetet i Agder 2014 The anaerobic digestion process involves the decomposition of the organic matter to yield biogas; gas that is mainly composed of methane and carbon dioxide with traces of some other gases. This process is used for different purposes including municipal waste treatment, wastewater treatment, fertilizer production, and farm wastes disposal as well as energy production. It is accomplished in three main stages; hydrolysis, acidogenesis and methanogenesis with each of the stages achieved by specific microorganisms that are active in limited ranges of operational and environmental conditions. These conditions are controlled to ach…