The CO2 Geological Storage: how it works Salvatore Lombardi Carbonia, Centro Ricerche Sotacarbo, 27 novembre 2014
Contents of the presentation Notes on CO2 Geological Storage (CGS) How it works How we may monitor the stored CO2 migration Site characterization and monitoring at Sulcis area Comments Carbonia, Centro Ricerche SOTACARBO, 27/11/2014
CO 2 geological storage options
What is stored CO 2 like? gas or liquid? Answer: gas for the viscosity liquid for the density T=100 C, P=280bar (2800m) density (kg/m3) viscosity (cp) supercritical 615 0.05 CO 2 water 804 0.16 gas (methane) 150 0.02
Permeable rocks (reservoir) 500 µm
Impermeable rocks (overburden) Clay At Italian suitable sites for CGS clay thiknes range from few hundreds metres up to 2000 metres Geol. Uni Köln
The outcropping anticlines in the Cellino Formation (Lower Pliocene) SW NE N
A seismic image of thrust-related fold typical trap example in the Periadriatic basin Lower Pliocene Quaternary Lower Pliocene Quaternary Lower Pliocene (G. Margaritae zone) Adriatic plate carbonate succession (Trias- Miocene) Top Gessoso Solfifera Formation (Messinian)
How we know it works By geological evidences. For example: From the studies of natural CO2 and CH4 fields where gases are trapped for millions of years From the studies on gas migration mechanisms By experience, such as: Man made gas storage (CH4, 4He, etc.) Injection tests Injection of gases for EOR (Enhanced Oil Recovery)
Oil and methane fields In Italy We learn by nature The age of methane fields range from 1 up to 5 M years while the age of oil field range from 20 up to 50M years
Fluids may migrate to the surface? No, if the site selected is an appropriate one. So site selection is of paramount importance Migration may occur through: Wells Faults if recent and/or seismogenic
Natural Open Lab: Geological and gas migration modellling trrough faults Fault analysis -Fault zone architecture reflects the degree to which the processes of strain localization vs. strain distribution compete in time and in space along the fault trace. -This relationship control the fault permeability and therefore gas migration Rome University: ENI, Schlumberger contracts Controlling factors of K: Lithology Fault scale and type Deformation style and history P & T history Component percentage, of K, and anisotropy Fossen, 2010 K ma Kx mi n
Gas migration trough faults Gas migration at Fiumicino (Rome) extensive tectonics
Radon in soil gas during 1997 Umbria earthquake September 1998 September 1997 Data from the first two campaigns reveal relatively low Rn values (>100 Bq/l) homogenously distributed September 1999 October 1997 0 0.1 0.2 km linear anomaly
How we may monitor gas migration toward surface? Many geophysical, geological an geochemical methods exist already Several of them may be used for studying precursor signal
Examples of monitoring
Sleipner CO 2 injection Monitoring at reservoir level Time-lapse seismic data 1994 Utsira Fm. CO 2 well 2001 CO 2 plume in map view 2008 2008-1994 Courtesy Statoil/CO2STORE project
Soil gas survey as precursor signal fo gas migration toward surface CH4 = 900 ppm CO2 = 7% He = 5ppm sinkholes recent sinkhole sept 03 CO2 0.05 up to 70% CH4 0.2 up to 19396ppm
New sinkhole 4m
Gas composition: CO2 97% CH4 230 ppm He 15 ppm
Research activity at Sulcis area (Sardinia) Funded by: Sardinia Region and Ministero Attività Produttive Research Institutions: Sotacarbo, Enea, Cagliari University, Sapienza Rome University, INGV, OGS, RSE
Summary of the Present Research activities (2014) in the Sulcis area: site selection and monitoring Activities Revision of the available geological and structural data Soil gas survey to define the baseline Soil gas profile across faults Geochemical Continuous monitoring (5 sites) Seismic monitoring (INGV) Reinterpretation of 100 km of seismic lines Acquisition and analyses of core samples from 2 wells (450 m of depth - 1000m depth) Fracture modeling for the seal and the reservoir rock volumes 3D geological model
Sulcis area: geological modeling and faults/fracture analysis Magmatic intrusion reworking as fault Frequency analysis of fractures Coal Mine field Well Top reservoir Cluster analysis of fault population available for storage - deeper than 900 m FAULT Carbonia, Centro Ricerche SOTACARBO, 27/11/2014
Research activities 2014 in Sulcis area: soil gas profile across faults Soil gas profiles allow : detecting leakage along faults constructing conceptual models of fluid migration along fault Provides experimental parameters for USA - Italy CCS meeting, Washington, DC, September 30 numerical modeling
Research activities 2014 in Sulcis area: Continuous monitoring (6 sites) Recording CO2 variability through time Carbonia, Centro Ricerche SOTACARBO, 27/11/2014
2015-2016 activities in the Sulcis basin Acquisition of: More seismic lines Better definition of geological model Gas migration model through faults Injection tests at shallow depths (about 300m) through faults 2 wells at depths ranging from 1500 to 2000m Extension of the network of monitoring station to the fault systems Extension of the researches offshore where the reservoir is deepening Public awareness: starting a dialogue with stakeholders on Sulcis perspective and CCS Building infrastructures to use Sulcis area as an international open lab (ECCEL EC project)
Sulcis area as an international Open Lab Infrastructure open to international researchers open as demonstrative site to general public Multiple CO2 Injection tests through faults at shallow depth To study CO2 migration trough faults To test geochemical (in house made and low cost CO2 sensors)l and geophysical monitoring tools To study water-gas-rock interactions To study boundary conditions for a controlled and safe CO2 storage USA - Italy CCS meeting, Washington, DC, September 30
Final remarks CO2 geological storage mimics natural gas reservoirs In a well selected storage site leakage is not expected to occur In case of gas migration toward the surface through faults generally anomalies are spot type and quite small in dimension (i.e. little impact on the shallow environments) Leakage through wells: experience for managing eventual leaks already exist in the oil and gas industry Monitoring tools A wide range of monitoring tools are available. The fate of injected gas can be traced from the reservoir up to the surface with enough accuracy and reliability CGS Europe researchers meet science journalists, April 8, 2013 Venice, San Servolo Island
Thanks for your attention salvatore.lombardi@gmail.com