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| Titel |
Chemical, mineralogical and molecular biological characterization of the rocks and fluids from a natural gas storage deep reservoir as a baseline for the effects of geological hydrogen storage |
| VerfasserIn |
Daria Morozova, Monika Kasina, Jennifer Weigt, Dirk Merten, Dieter Pudlo, Hilke Würdemann |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250096232
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| Publikation (Nr.) |
 EGU/EGU2014-11725.pdf |
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| Zusammenfassung |
| Planned transition to renewable energy production from nuclear and CO2-emitting
power generation brings the necessity for large scale energy storage capacities. One
possibility to store excessive energy produced is to transfer it to chemical forms like
hydrogen which can be subsequently injected and stored in subsurface porous rock
formations like depleted gas reservoirs and presently used gas storage sites. In order to
investigate the feasibility of the hydrogen storage in the subsurface, the collaborative
project H2STORE ("hydrogen to store") was initiated. In the scope of this project,
potential reactions between microorganism, fluids and rocks induced by hydrogen
injection are studied. For the long-term experiments, fluids of natural gas storage are
incubated together with rock cores in the high pressure vessels under 40 bar pressure
and 40°C temperature with an atmosphere containing 5.8% He as a tracer gas,
3.9% H2 and 90.3% N2. The reservoir is located at a depth of about 2 000 m, and is
characterized by a salinity of 88.9 g l-1 NaCl and a temperature of 80°C and
therefore represents an extreme environment for microbial life. First geochemical
analyses showed a relatively high TOC content of the fluids (about 120 mg l-1) that
were also rich in sodium, potassium, calcium, magnesium and iron. Remarkable
amounts of heavy metals like zinc and strontium were also detected. XRD analyses
of the reservoir sandstones revealed the major components: quartz, plagioclase,
K-feldspar, anhydrite and analcime. The sandstones were intercalated by mudstones,
consisting of quartz, plagioclase, K-feldspar, analcime, chlorite, mica and carbonates.
Genetic profiling of amplified 16S rRNA genes was applied to characterize the
microbial community composition by PCR-SSCP (PCR–Single-Strand-Conformation
Polymorphism) and DGGE (Denaturing Gradient Gel Electrophoresis). First results
indicate the presence of microorganisms belonging to the phylotypes alfa-, beta- and
gamma-Proteobacteria and Actinobacteria. Sequences of these organisms have been found in
subsurface environments before, e.g. in saline, hot, anoxic, and deep milieus. Due to
the saline and hyperthermophilic reservoir conditions, the quantification of those
microorganisms by DAPI staining revealed very low cell numbers of about 102 cells
ml-1.
Investigations of the microbial community composition, mineralogy and fluid
chemistry after 6 months of incubation are in progress to determine to what extent
hydrogen injection may contribute to a shift in the microbial community structure and
abundance, microbial-mineral interactions and hydrogen-based methanogenesis. |
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