Performance of European biogas plants towards methane emissions
© Lehrstuhl fĂĽr Abfallverwertungstechnik und Abfallwirtschaft der MontanuniversitĂ¤t Leoben (11/2022)
Biogas or biomethane, resulting from the biological treatment of organic matter by anaerobic digestion, is a renewable energy source used for electricity production, heating and in transportation and can substitute fossil gas. Therefore, biogas production is described as a sustainable strategy for reducing anthropogenic greenhouse gases (GHG). However, the positive environmental impact depends in particular on emissions that might occur within the biogas production and utilization chain. Although numerous scientific studies investigated CH4 emissions from biogas plants, there is still a lack of reliable and representative emission data. As stated in the United Nations Framework Convention on Climate Change, the member countries are obliged to report their national GHG inventories according to the Intergovernmental Panel on Climate Change (IPCC) guidelines.
The potential of insects in waste management â€“ an introduction to possible applications
© Lehrstuhl fĂĽr Abfallverwertungstechnik und Abfallwirtschaft der MontanuniversitĂ¤t Leoben (11/2020)
In order to remain competitive for achieving a circular economy we need to consider even more alternative pathways to close the loop for material and waste streams down to a nutritional level. A sustainable and value adding strategy is the intensified rearing and use of insects, in particular the use of edible species as human food and animal feed.
Legal framework of the EEG 2017 for anaerobic Digestion plants based on waste and residues
© Wasteconsult International (5/2017)
The 2017 German Renewable Energy Sources Act (EEG 2017) came into force on 1st January 2017. This revision altered the German mechanism to support the Generation of energy from renewable sources for the first time since the law originally took effect in 2000, moving from fixed feed-in tariffs to an auction model. The new requirements create completely new challenges for plant operators and public authorities involved with implementation.
European Harmonization of Methods to Quantify Methane Emissions from Biogas Plants
© Lehrstuhl fĂĽr Abfallverwertungstechnik und Abfallwirtschaft der MontanuniversitĂ¤t Leoben (11/2016)
In the past years, attempts were undertaken to quantify single emission sources as well as overall emissions from biogas plants using on-site (direct) and remote sensing (indirect) methods. While measurements on site often focus on one type of CH4
sources, remote sensing methods cover the overall emission plume. Among the current available emission measurement techniques, none is in a position to be recognized as the best international reference. Therefore, the establishment of a scientifically based standardization and harmonization of methods would greatly contribute to the assessment of the fugitive emissions from biogas plants.
Fast methanification of swine manure as an example for substrates with low organic content
© Agrar- und Umweltwissenschaftliche FakultĂ¤t UniversitĂ¤t Rostock (6/2015)
A biogas reactor of 45 mÂł was fed with pure swine manure. A straw layer worked as an anaerobic filter on top of the fluid. The manure was continuously circulated to irrigate the straw. Hydraulic retention time (HRT) of straw was 45 days. HRT of manure was reduced from 45 to 7.5 days within one year. Average concentration of volatile solids (VS) of manure only was 1.8 %. We varied VS concentration and temperature to simulate normal disturbances of operation. Gas production normalized within one day after each short heating interruption. Variations of VS concentration had no negative influence on the Operation as a whole. After two months, a zone with granular sludge in autonomous fluidization was observed just below the straw layer. This shows that the reactor is a hybrid biogas reactor containing a fixed bed on the top, and an UASB zone below.
Experiences with Power-to-Gas â€“ upgrading technology for sewage treatment plants?
© Wasteconsult International (5/2015)
Methane produced in a biological process using surplus electricity from renewable sources such as wind and the sun is being fed into the natural gas grid for the first time in Allendorf (Eder), Germany. The first system of this type in the world went into Operation in early March. The MicrobEnergy (Viessmann Group) demonstration plant had been in operation at the Schwandorf sewage works until the end of December 2014.
System for mixing the contents of a biogas digester by means of cyclically drawing off the product gas
© Wasteconsult International (5/2015)
Conventional digesters fed on high solids material like manure, energy crops and/or other fibrous matter suffer from various disadvantages, among which :
- the need to use powerful agitating and mixing systems in the digester in order to avoid the formation of a floating crust on top of the contents
- the need to dilute the contents of the digester in order to be able to mix it, with as a result an increase of the size of the digester
- the high thermal needs of the digester due to ist size
- the high electricity consumption of the mixing system
- the high investment costs of the system (size and auxiliary equipment).