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  • The effect of rising concentration of atmospheric carbone dioxide on crop production
    81-84
    Views:
    111

    In the atmosphere, the amount of carbon dioxide and other greenhouse gases are rising in gradually increasing pace since the Industrial Revolution. The rising concentration of atmospheric carbon dioxide (CO2) contributes to global warming, and the changes affect to both the precipitation and the evaporation quantity. Moreover, the concentration of carbon dioxide directly affects the productivity and physiology of plants. The effect of temperature changes on plants is still controversial, although studies have been widely conducted. The C4-type plants react better in this respect than the C3-type plants. However, the C3-type plants respond more richer for the increase of atmospheric carbon dioxide and climate change.

  • Biomethane production monitoring and data analysis based on the practical operation experiences of an innovative power-to-gas benchscale prototype
    399-410
    Views:
    348

    Power-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.

  • Regional economic achievements and reindustrialisation in Hajdú-Bihar county
    65-74
    Views:
    175

    The North Great Plain region is one of the backward regions of Hungary. The low level of economic development is mainly due to the lack of industrial development. The region is poor in natural resources, its main resources are land, natural gas fields, carbon dioxide, thermal water and the clay mineral stock.
    The structure of GDP per capita of the county is different than the country average mainly because of the high proportion of agriculture.
    The proportion of the industry and the building industry is not significant. Of the various service provider sectors, trade, transport and telecommunications have a small proportion, while financial and economic service providers have even lower share, which is due to the fact that these sectors are mostly concentrated in Budapest. The share of public and human service prodivers is higher than average due to the University of Debrecen.
    The GDP which expresses the economic development of the county in a complex way increased four times its previous value in nominal value between 1995–2009. However, if the real value is considered, the increase is less than 25%, as opposed to the country average, which was less than 40%.
    The most complex index of the development level of an economy is GDP expressed either in nominal or real value. If expressed in dollars, GDP is suitable for international comparison with the correction based on the purchasing power parity per person.
    The county represents 4.3% of the people employed in the industrial sector in Hungary, while its share in industrial production is only 3.3% which is lower than the regional and population share of the county within Hungary. As regards industrial production per person, Hajdú-Bihar was the 10th county in Hungary; therefore, it is considered to be a less industrialised county.
    The product structure of GDP is suitable for drawing useful development conclusions, but the result is more reliable if the income creation ability is also analysed on the basis of the employment structure.