| Title | Survey for Prospective Utilisation of Geotherfnal Energy in Kosice Basin |
|---|---|
| Authors | Andrea Vranovska & Dusan Bodis |
| Year | 1999 |
| Conference | European Geothermal Conference |
| Keywords | Geothermal energy, geqthermics, hydrogeothermics, geochemistry, Mesozoic reservoir, Kosice basin |
| Abstract | The aim of two geothermal wells realised in Kosice basin, in Durkov geothermal structure, was verifying the source of geothermal water for its prospective utilisation in town Kosice. The existence of geothermal reservoir was originally found by oil-gas investigation in late 60. The first phase of work on Kosice heating project utilisiug geothermal energy included drilling and completion of two geothermal wells - vertical GTD-1 and directional GTD-2. The results of drilling and testing of doublet for reinjection system - GTD-1 and GTD-2 - proved the presence of geothermal water in Mesozoic dolomites, mainly in fractured top zone on the border with basal Karpatian conglomerates in depth 2100 - 3200 m. GTD-1 discharging by free flow has average flowrate 56 Us, temperature of geothermal water on the wellhead 125?C and TDS 30 g/l. GTD-2 discharging by free flow flowrate of 70 Us, temperature on wellhead 124OC. TDS 28 g/l. The chemical character of water found in both wells is remarkable sodium chloride type, gas content represent 97 vol% COz 15 vol% N2 and 1 vol% CR. The origin of geothermal water according to chemical and isotopic analyses seems to be meteoric water infiltrated into Neogene formations and salted by trapped sea water and consequently penetrated to the lower parts in Mesozoic dolomites. On the base of well test results geothermal structure seems to be hydrogeologically and geochemically confined, its utilisation is possible by reinjection. Chemical composition of water indicates scaling problems. Promising results of wells exceeded expected parameters and realisation of Kosice heating project utilising geothermal energy with heat output IOOMW should be done in near future. Aiming in output of 100 MW incorporates realisation of 8 production and 8 reinjection wells. |