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Bioreactor in the service of sustainable development
111-118Views:126The control of our relationship with our environment is one of the greatest challenges of the 21st century. This has an effect on the economic and social processes and the human activities. All of these are included in a new developmental strategy: the strategy of sustainable development.
The strategy of sustainable development prevails by the new technologies and it is realized on high-tech level as the fermentation manipulation of organic materials, biogas production and production of “green” electric current.
One of Europe’s largest bioreactors has been established in Nyírbátor in Hungary at first (chief executive: Mihály Petis). -
Biomethane production monitoring and data analysis based on the practical operation experiences of an innovative power-to-gas benchscale prototype
399-410Views:350Power-to-gas (P2G) is referred to technologies that convert carbon dioxide into methane. Both bio- and chemical catalysts may be used for conversion purposes. One of the most disruptive biotechnologies was developed by the University of Chicago (IL) (publication number: EP2661511B1), using a robust, highly selective, patented strain of Archaea. Electrochaea GmbH has developed an innovative bench-scale P2G prototype unit, which uses this highly efficient Archaea strain, specialized components and specifically developed control strategies. The structure and the components of the prototype are equivalent with the functional parts of the currently largest commercial scale biomethanation BioCat plant located in Avedøre, Denmark (www.biocat-project.com). Power-to-Gas Hungary Kft. has committed to further develop this innovative technology. The first steps of this development have been taken by operating the benchscale unit and analyzing the data of the operating periods.
The prototype is operated based on weekly campaigns. During continuous operation, H2O is generated as a by-product of methane. Therefore, approximately 200 ml of biocatalyst is discharged each day and concentrated media containing macro and micronutrients are injected into the reactor to maintain media composition. The laboratory staff records all gas composition data each morning. The gas composition is measured every 12 minutes by an Awite AwiFlex Cool+ gas analyzer. Within this article, we analyze the collected datasets containing more than 12 000 records and present the first practical experiences of the operations of the innovative power-to-gas bench-scale prototype.
The analysis of the collected gas composition data of the product gas already provides important data for modelling the commercial-scaled processes. The average value of VVD was about 40 l/l/d in the period under review. Further increase of the methane content can be achieved by introduction of higher mixing energy and by increasing pressure levels in the bioreactor (as demonstrated in the BioCat plant – data not shown here) – both of which are strategies envisioned for the commercial plant. In routine activities (turn on, shut down, continuous operation) we could verify the high robustness of the biocatalyst and the base connection between the registered datasets and performed test results.
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Ecotoxicological impact of DON toxin on maize (Zea mays L.) germination
35-40Views:148Fusarium graminearum is one of the most significant arable pathogen in Hungary, and various types of trichothecene mycotoxins (mostly DON, deoxynivalenol) are detected most commonly in cereals (Biró et al., 2011). Fusarium infection and mycotoxin production could not be eliminated, and infected maize by Fusarium sp. cannot be exploited as food, seed, or animal feed. However it can be raw material of biogas production. In this research we would like to investigate the content and effect of the toxin in the end product of biogas production on plant germination. The Fusarium sp. can cause mildew and seedling mortality in seed of maize (Zea mays L.), so we examine the effect of this on germination. In preliminary examination Fusarium sp. was not detected in the bioreactor of the Institute after the retention time (30 day), however it can be assumed that during the hydrolysis of the fungus growth and mycotoxin production also increased exponentially. There were no appropriate tools to detect the toxin in the end product of biogas production so modelling of anaerobic hydrolysis was necessary. The effects of hydrolyzed product for germination were also detected.