Speaker
Dr
Peter KRALJ
(Gejzir Consulting, EON Research Centre)
Description
In spring 2004, a 1857 m deep geothermal well Be-2/03 was drilled in the Benedikt place, north-eastern Slovenia. The temperature of thermal water exceeds 100 °C. The water belongs to the Na-HCO3 hydrogeochemical facies and has been classified as a CO2-rich healing mineral water suitable for drinking, bottling and balneology. Free degassing gas is almost pure CO2 (99.9 volume %). Major ion composition is dominated by sodium (1750 ppm) and bicarbonate (4700 ppm). The well testing would be an expensive and difficult operation owing to the high water temperature. For that reason, the Municipality of Benedikt, as the
well owner decided to construct a part of the planned district heating project, and in this way, usefully lowered the waste water temperature.
Owing to very high investment costs that could not be carried by the Municipality itself, and very poor engagement of the responsible governmental institutions, the Municipality council decided to make a contract with the company Gejzir Consulting from Ljubljana in the beginning of the year 2006. The Municipality of Benedikt is the well owner and ensured an uptake of 5L/sec of thermal water to Gejzir Consulting for construction of the first stage of
district heating. District heating encompasses public dwellings – the Municipality building, gymnasium, primary school and kindergarten that consume altogether 20 % of total Municipality consumption. Heat station has the power of 600 kW and annually produces 2.000 MWh of heat. Gas separator and heat exchanger are located at the production well in order to simplify the system operation. Energetically used thermal water is cooled in a nearby pool.
The inflow of thermal water from the production well is regulated automatically with respect to the outflow temperature from the heat exchanger which is constant and amounts to 40 ºC.
The water undergoes further cooling in the pool and is less than 30 ºC when disposed into a small creek. After the enlargement of the district heating network, construction of a small power plant and a spa centre, energetically used thermal water will be reinjected into the primary aquifer. The cooling pool will not be needed any more.
The whole project of district heating is characterised by 3,3 MW of power and annual production of 4.000 MWh.
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P. KRALJ
![P. KRALJ][16]
[16]: https://indico.cern.ch/event/263557/picture/50.jpg
Author
Dr
Peter KRALJ
(Gejzir Consulting, EON Research Centre)
