Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 5

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
w słowach kluczowych:  enhanced geothermal systems
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
Petrophysical investigations are fundamental to natural resource exploration. In order to recognise the geothermal potential of sedimentary rocks in central Poland, 259 samples were collected from prospective deep-lying geothermal reservoirs. Parameters measured include bulk density, skeletal density, effective porosity, permeability, average pore diameter and specific surface. Results indicate that at great depths (mostly > 3,000 m below surface) sedimentary rocks show low values of porosity (mainly less than 5%) and permeability (only sporadically in excess of 1 md). These values call for a petrothermal use of reservoirs, for which an Enhanced Geothermal System (EGS) was developed. Reservoirs suited for the EGS are Carboniferous and Lower Triassic sandstones in the central part of Poland (Mogilno-Łódź Trough region and a small part of the Kujawy Swell and Fore-Sudetic regions). In addition, Carboniferous limestones in this area are potentially prospective.
The article presents an overview of developing unconventional geothermal systems, such as Hot Dry Rock Systems (HDR), where is used the heat of dry rock and enhanced system with smali water tributary called Enhanced Geothermal Systems (EGS). These systems provide utilization of geothermal energy in reservoirs (i.a. granites) where conventional methods are not possible to use. Operation HDR/EGS involves the use rock heating through warming medium, which flowing between the production and injection boreholes. In most cases medium introduced artifically by hydraulic fracturing. Currently, most of the projects HDR/EGS is in the implementation phase. Based on gathered materials an analysis of the construction and exploitation geothermal systems. Take into account geological and drilling aspects.
The fast-growing discipline in the field of geothermal research is the prospecting for geological structures useful for HDR (Hot Dry Rock) or EGS (Enhanced Geothermal Systems) technologies. In Poland, an interesting area for such research is the Sudetes, particularly the Karkonosze Mts. pluton and Fore-Sudetic Block. The article presents issues of scientific projects prepared in the Division of Renewable Energy of Mineral and Energy Economy Research, Institute of the Polish Academy of Sciences in Kraków, related to the recognition of geothermal conditions of the Sudetic region. On the background of global research, these projects demonstrate an innovative character mainly by targeting research on the analysis of tectonics and volcanism of the Sudetes as important factors of the presence of local positive thermal anomalies. Implementation of the afore-mentioned projects would create the possibility of extending still modest knowledge of the deep geological structure of the Sudetic area.
Content available remote Ogólna charakterystyka wspomaganych systemów geotermalnych
Spośród systemów geotermalnych szczególnie interesujące są głębokie systemy geotermalne wykorzystujące ciepło skał. Technologia pozyskiwania energii cieplnej zgromadzonej w skałach przeszła ewolucję od koncepcji "suchych gorących skał" (Hot Dry Rocks - HDR) do technologii wspomaganych systemów geotermalnych (Enhanced Geothermal System - EGS). Wybór potencjalnych miejsc do lokalizacji zbiorników EGS powinien być realizowany na podstawie odpowiednich kryteriów i metodyki. Mapa temperatur na głębokości 5 km posłużyła jako podstawa charakterystyki potencjału i typów EGS w Europie. Obszar Polski charakteryzuje się niskim potencjałem EGS, potencjalnymi obszarami, gdzie można by poszukiwać lokalizacji zbiorników EGS są głębokie baseny sedymentacyjne na obszarze Niżu Polskiego.
Among geothermal systems the deep geothermal systems using heat of rocks are specially interesting. The technology of thermal energy accumulated in rocks winning, has undergone evolution from conception of Hot Dry Rocks (MDR) up to the technology of Enhanced Geothermal System (EGS). Selection of potential places for location of EGS reservoirs should be realized on the basis of proper criterions and methodology. The map of temperatures on the depth of 5 km was used as the basis of potential characteristic and types of EGS in Europe. The Polish territory is characterized by Iow potential of EGS. The potential areas where one could search location for EGS reservoirs are the deep sedimentation basins on Polish Lowland.
The technical feasibility of geothermal power production in a low enthalpy environment will be investigated in the geothermal site at Groß Schönebeck, North German Basin, where a borehole doublet was completed in 2007. In order to complete the Enhanced Geothermal System, three massive hydraulic stimulations were performed. A seismic network was deployed including a single 3-component downhole seismic sensor at only 500 m distance to the injection point. Injection rates reached up to 9 m3/min and the maximum injection well-head pressure was as high as ∼60 MPa. A total of 80 very small (–1.8 < MW < –1.0) induced seismic events were detected. The hypocenters were determined for 29 events. The events show a strong spatial and temporal clustering and a maximum seismicity rate of 22 events per day. Spectral parameters were estimated from the downhole seismometer and related to those from other types of induced seismicity. The majority of events occurred towards the end of stimulation phases indicating a similar behavior as observed at similar treatments in crystalline environments but in our case at a smaller level of seismic activity and at lower magnitudes.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.