Abstract Loss of injectivity in the near wellbore region of coalbeds during CO 2 injection is a l... more Abstract Loss of injectivity in the near wellbore region of coalbeds during CO 2 injection is a limiting factor for its exploitation as potential reservoir for geological storage of CO 2. Current research investigated the potential of thermal stimulation (thermal fracturing through cyclic freezing and thawing) of coal at the wellbore in order to achieve better injectivity during enhanced coalbed methane (CBM) recovery and CO 2 storage. Moisture saturated coal samples were subjected to freezing and thawing cycles to establish the effects of this ...
Atzbach–Schwanenstadt natural gas field located in Upper Austria Molasse Foreland basin was one o... more Atzbach–Schwanenstadt natural gas field located in Upper Austria Molasse Foreland basin was one of the four European sites selected for subsurface CO2 storage feasibility/performance evaluation in the recently completed EU-funded research project CASTOR. The objectives of the coupled reservoir-geomechanical modelling effort at Aztbach-Schwanenstadt gas field were: 1) evaluation of the hydro-mechanical response of the reservoir rock and overburden formations to
The oxy-fuel combustion CO2 capture route and post-combustion CO2 capture route involve different... more The oxy-fuel combustion CO2 capture route and post-combustion CO2 capture route involve different energy consumption rates and subsequent environmental impacts. The holistic perspective offered by Life Cycle Assessment (LCA) can help decision makers to compare alternative CO2 capture and storage technologies in a life cycle perspective. This paper, at first, introduces the principles of the dynamic LCA model developed for oxy-fuel combustion and post-combustion power generation with CO2 capture, transport and injection processes. Next, a comparative life cycle assessment of alternative CO2 capture technologies is presented. Results show that, at life-cycle level, the post-combustion and oxy-fuel combustion CCS cases can reduce the life-cycle Global Warming Potential (GWP) by 78.8% and 80.0% respectively compared to conventional power plant without CCS. Other environmental impacts, such as Ecotoxicity, Human toxicity and Acidification, vary significantly with the different CO2 capture routes employed. Finally, by comparing the results obtained with the most recent LCA studies of post-combustion power generation with CO2 capture and storage, it is shown that the plant level, gate-to-gate studies provide significantly variable results and generally overestimate life cycle environmental impacts.
This paper presents a numerical simulation study of a CO2 core flooding test performed on a Tako ... more This paper presents a numerical simulation study of a CO2 core flooding test performed on a Tako sandstone sample, which measured 14.5 cm long and 3.68 cm in diameter. During the test, supercritical CO2 (at 10 MPa and 40 ∘C) was injected into one end of the horizontal core and a X-ray CT scanner (with a resolution of 0.35 mm×0.35 mm) was employed
CO2GeoNet is a Network of Excellence on the geological storage of CO2, initiated by the EC’s 6th ... more CO2GeoNet is a Network of Excellence on the geological storage of CO2, initiated by the EC’s 6th research framework programme in 2004 and integrating Europe’s key research institutes to create a scientific reference body dedicated to the development of CO2 geological storage as a viable option for mitigating climate change. It has gained international recognition through bodies such as CSLF
Concern about increasing levels of trace elements in the environment has led to the development a... more Concern about increasing levels of trace elements in the environment has led to the development and implementation of a global programme to determine the current baseline levels of these chemicals in the Earth's surface. The FORum of European Geological Surveys (FOREGS) has recently published a geochemical database for Europe, while progress on similar databases is continuing in other major regions of the world. The FOREGS database comprises multimedia samples collected at a resolution of approximately 72x72 km from 26 European countries. This enables the investigation of the factors governing geochemical variation on a continental scale, potentially allowing contributions of natural processes to be appreciated prior to setting environmental quality standards. This paper investigates the variation in European topsoil geochemistry using factorial kriging analysis, which performs principal components analysis at different spatial scales. The results are interpreted with the aid of a GIS database. Four spatial scales were identified: a nugget component representing variation over a range less than the sampling density; a 'short' scale component with a range of 296 km; an 'intermediate' scale component (875 km); and a 'long' scale component (1750 km). The first three principal components (PCs) of the nugget covariance matrix explained 22.2% of the overall variance, representing local variation in geology, land use, weathering and organic matter content. The first two PCs of the short range structure explained 12.6% of the variance, representing variation according to the major structural divisions of Europe, and to carbonate content. The first PC of the intermediate structure explained 7.2% of the variance and was found to relate to glacial history and Quaternary deposition. Finally, the first three PCs of the long range structure explained 29.6% of the variance and represented variation due to mineralisation, soil texture, climate and possibly anthropogenic contamination.
Artificial neural networks (ANNs) provide a quick and flexible means of creating models for river... more Artificial neural networks (ANNs) provide a quick and flexible means of creating models for river flow prediction, and have been shown to perform well in comparison with conventional methods. However, if the models are trained using a dataset that contains a limited range of values, they may perform poorly when encountering events containing previously unobserved values. This failure to generalise
International Journal of Surface Mining, Reclamation and Environment, 2000
The main objective of the diamond wire sawing tests presented in this paper was to investigate th... more The main objective of the diamond wire sawing tests presented in this paper was to investigate the diamond wire performance when sawing different granites in different orientations with respect to the rock microstructure. The work reported was carried out at the stoneyard, using stationary machines, and by sawing granite blocks free from major discontinuities. The test blocks were cut in
Abstract Loss of injectivity in the near wellbore region of coalbeds during CO 2 injection is a l... more Abstract Loss of injectivity in the near wellbore region of coalbeds during CO 2 injection is a limiting factor for its exploitation as potential reservoir for geological storage of CO 2. Current research investigated the potential of thermal stimulation (thermal fracturing through cyclic freezing and thawing) of coal at the wellbore in order to achieve better injectivity during enhanced coalbed methane (CBM) recovery and CO 2 storage. Moisture saturated coal samples were subjected to freezing and thawing cycles to establish the effects of this ...
Atzbach–Schwanenstadt natural gas field located in Upper Austria Molasse Foreland basin was one o... more Atzbach–Schwanenstadt natural gas field located in Upper Austria Molasse Foreland basin was one of the four European sites selected for subsurface CO2 storage feasibility/performance evaluation in the recently completed EU-funded research project CASTOR. The objectives of the coupled reservoir-geomechanical modelling effort at Aztbach-Schwanenstadt gas field were: 1) evaluation of the hydro-mechanical response of the reservoir rock and overburden formations to
The oxy-fuel combustion CO2 capture route and post-combustion CO2 capture route involve different... more The oxy-fuel combustion CO2 capture route and post-combustion CO2 capture route involve different energy consumption rates and subsequent environmental impacts. The holistic perspective offered by Life Cycle Assessment (LCA) can help decision makers to compare alternative CO2 capture and storage technologies in a life cycle perspective. This paper, at first, introduces the principles of the dynamic LCA model developed for oxy-fuel combustion and post-combustion power generation with CO2 capture, transport and injection processes. Next, a comparative life cycle assessment of alternative CO2 capture technologies is presented. Results show that, at life-cycle level, the post-combustion and oxy-fuel combustion CCS cases can reduce the life-cycle Global Warming Potential (GWP) by 78.8% and 80.0% respectively compared to conventional power plant without CCS. Other environmental impacts, such as Ecotoxicity, Human toxicity and Acidification, vary significantly with the different CO2 capture routes employed. Finally, by comparing the results obtained with the most recent LCA studies of post-combustion power generation with CO2 capture and storage, it is shown that the plant level, gate-to-gate studies provide significantly variable results and generally overestimate life cycle environmental impacts.
This paper presents a numerical simulation study of a CO2 core flooding test performed on a Tako ... more This paper presents a numerical simulation study of a CO2 core flooding test performed on a Tako sandstone sample, which measured 14.5 cm long and 3.68 cm in diameter. During the test, supercritical CO2 (at 10 MPa and 40 ∘C) was injected into one end of the horizontal core and a X-ray CT scanner (with a resolution of 0.35 mm×0.35 mm) was employed
CO2GeoNet is a Network of Excellence on the geological storage of CO2, initiated by the EC’s 6th ... more CO2GeoNet is a Network of Excellence on the geological storage of CO2, initiated by the EC’s 6th research framework programme in 2004 and integrating Europe’s key research institutes to create a scientific reference body dedicated to the development of CO2 geological storage as a viable option for mitigating climate change. It has gained international recognition through bodies such as CSLF
Concern about increasing levels of trace elements in the environment has led to the development a... more Concern about increasing levels of trace elements in the environment has led to the development and implementation of a global programme to determine the current baseline levels of these chemicals in the Earth's surface. The FORum of European Geological Surveys (FOREGS) has recently published a geochemical database for Europe, while progress on similar databases is continuing in other major regions of the world. The FOREGS database comprises multimedia samples collected at a resolution of approximately 72x72 km from 26 European countries. This enables the investigation of the factors governing geochemical variation on a continental scale, potentially allowing contributions of natural processes to be appreciated prior to setting environmental quality standards. This paper investigates the variation in European topsoil geochemistry using factorial kriging analysis, which performs principal components analysis at different spatial scales. The results are interpreted with the aid of a GIS database. Four spatial scales were identified: a nugget component representing variation over a range less than the sampling density; a 'short' scale component with a range of 296 km; an 'intermediate' scale component (875 km); and a 'long' scale component (1750 km). The first three principal components (PCs) of the nugget covariance matrix explained 22.2% of the overall variance, representing local variation in geology, land use, weathering and organic matter content. The first two PCs of the short range structure explained 12.6% of the variance, representing variation according to the major structural divisions of Europe, and to carbonate content. The first PC of the intermediate structure explained 7.2% of the variance and was found to relate to glacial history and Quaternary deposition. Finally, the first three PCs of the long range structure explained 29.6% of the variance and represented variation due to mineralisation, soil texture, climate and possibly anthropogenic contamination.
Artificial neural networks (ANNs) provide a quick and flexible means of creating models for river... more Artificial neural networks (ANNs) provide a quick and flexible means of creating models for river flow prediction, and have been shown to perform well in comparison with conventional methods. However, if the models are trained using a dataset that contains a limited range of values, they may perform poorly when encountering events containing previously unobserved values. This failure to generalise
International Journal of Surface Mining, Reclamation and Environment, 2000
The main objective of the diamond wire sawing tests presented in this paper was to investigate th... more The main objective of the diamond wire sawing tests presented in this paper was to investigate the diamond wire performance when sawing different granites in different orientations with respect to the rock microstructure. The work reported was carried out at the stoneyard, using stationary machines, and by sawing granite blocks free from major discontinuities. The test blocks were cut in
Uploads
Papers by Sevket Durucan