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| Titel |
Microbial influence on mineral creation in carbon capture and storage (CCS) procedures |
| VerfasserIn |
Monika Kasina, Anne Kleyböcker, Daria Morozova, Marietta Liebrich, Maren Wandrey, Hilke Würdemann |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250057540
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| Zusammenfassung |
| Global climate changes connected with increasing emissions of CO2 into atmosphere require
the development of different carbon capture and storage (CCS) methods. One of the CCS
methods is mineral carbonation that relays on crystallization of stable carbonate minerals rich
in divalent cations (Ca2+, Mg2+, Fe2+) with CO2, which is one of the safest methods in CO2
storage. Composition and activity of microbial communities that change due to
CO2 injection can influence mineral dissolution and precipitation processes. In this
study we focus on microbial induced mineral formation. Microbial induced mineral
creation was studied in an artificial system characterized by high concentrations of
organic material (volatile fatty acid: 8000 mg l-1) and high concentrations of Ca2+
(200Â mg l-1), Mg2+ (130 mg l-1) and PO43- (1000 mg l-1) to better understand the
processes and the role of microorganisms. During laboratory experiments different
aggregates were produced depending on the concentration of divalent cations. The
size of aggregates depended on the concentration of Ca2+. Different minerals as
well as organic matter were detected in the aggregates and supplied first evidence
of the mechanism of mineral creation processes in these systems indicating the
involvement of phosphate accumulating bacteria. Small aggregates (ca. 2 cm diameter)
were formed as irregular spheres with a central nucleus. The nucleus was made of
organic matter mixed with crystalline phases like vivianite (Fe3(PO4)2 -
8H2O),
k-feldspar (KAlSi3O8), plagioclases (NaAlSi3O8 - CaAl2Si2O8), quartz (SiO2)
surrounded by layers (characteristic lamination) composed of organic acids (long chain
fatty acids - LCFA which bond Ca (Al) or Ca (Mg, Fe) - LCFA - Ca, aluminum
phosphate (AlPO4). Bigger aggregates (ca. 10 cm diameter) were created in the
presence of high Ca2+ concentrations (200 mg l-1). Their surface was composed of
organic acids (LCFA) which bond Ca (LCFA - Ca) and in the inner part apatite
(Ca5(PO4)3, Al, Ca-phosphates, Mg-phosphates were found. Long term in situ
experiments are carried out in high pressure vessels in order to characterize the
microbial impact on the reservoir components of a depleted natural gas field and to
assess the interaction with CO2 storage. In order to study mobilization effects of
supercritical CO2 rock cores will be incubated with different concentrations of
organic material and elevated concentrations of Ca2+, Mg2+, Fe2+ to characterize
changes in the microbial communities as well as the mineral composition. First
results of these experiments will be presented at the EGU General Assembly 2011. |
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