A5034087760- Methane Hydrates and Related Phenomena
- Hydrocarbon exploration and reservoir analysis
- Spacecraft and Cryogenic Technologies
- Atmospheric and Environmental Gas Dynamics
- CO2 Sequestration and Geologic Interactions
- Geology and Paleoclimatology Research
- Hydraulic Fracturing and Reservoir Analysis
- Climate change and permafrost
- Offshore Engineering and Technologies
- Geological Studies and Exploration
- Arctic and Antarctic ice dynamics
- Geophysical and Geoelectrical Methods
- Quantum, superfluid, helium dynamics
- Carbon Dioxide Capture Technologies
- Inorganic Fluorides and Related Compounds
- Geotechnical Engineering and Soil Mechanics
- Catalysts for Methane Reforming
- NMR spectroscopy and applications
- Industrial Gas Emission Control
- Geophysical Methods and Applications
- Coal Properties and Utilization
- Reservoir Engineering and Simulation Methods
- Membrane Separation and Gas Transport
- Advanced Power Generation Technologies
- Chemical Looping and Thermochemical Processes
GFZ Helmholtz Centre for Geosciences
2015-2024
University of Potsdam
2021-2023
Springer Nature (Germany)
2021
Max-Planck-Institut für Kohlenforschung
2003
Max Planck Society
2003
The presence of natural gas hydrates at all active and passive continental margins has been proven. Their global occurrence as well the fact that huge amounts methane other lighter hydrocarbons are stored in led to idea using hydrate bearing sediments an energy resource. However, remain stable long they mechanical, thermal chemical equilibrium with their environment. Thus, for production from sediments, least one these states must be disturbed by depressurization, heating or addition...
Gas hydrate production is still in the test phase. It only now that numerical models are being developed to describe data and scenarios. Laboratory experiments carried out rationale of conceptual deliver input data. Major experimental challenges include (I) simulation a natural three-phase system sand–hydrate–liquid with known high saturations (II) transport behavior as deduced from field The large-scale reservoir simulator (LARS; 210 L sample) at GFZ has met these allowed for first gas...
The unexpected coexistence of structure I (s I) and II II) methane hydrates under conditions where only s should be stable (see picture) suggests that the initial product is determined by kinetics. state as well transformation kinetic into thermodynamically hydrate was documented microscopic visual observation Raman spectroscopy.
Microscopy, confocal Raman spectroscopy and powder X-ray diffraction (PXRD) were used for in situ investigations of the CO2-hydrocarbon exchange process gas hydrates its driving forces. The study comprises exposure simple structure I CH4 hydrate mixed II CH4–C2H6 CH4–C3H8 to gaseous CO2 as well reverse reaction, i.e., conversion CO2-rich into hydrate. In case hydrates, a presence from supposedly more stable less was observed. PXRD data show that requires longer initiation times, structural...
Since huge amounts of CH4 are bound in natural gas hydrates occurring at active and passive continental margins permafrost regions, the production from hydrate-bearing sediments has become more interest. Three different methods to destabilize release discussed principle: thermal stimulation, depressurization chemical stimulation. This study focusses on stimulation using a counter-current heat-exchange reactor for situ combustion CH4. The principle as method hydrate bearing been introduced...
The intensive study of hydrate-bearing sandy sediments, a possible source fossil energy for future generations, leads to an accumulation information from field studies, laboratory and modeling. This is used create conceptual models hydrate deposit genesis helping assess the value experimental studies on artificially formed sediments. We present example simulation formation methane dissolved in water, which assumed be most likely natural process highly concentrated Measurements concentration...
Formation and thermal based dissociation of methane pore space hydrate has been studied at various initial saturations heating rates utilizing a 1.3 cm3 glass bead sample pack. Initial formation occurred rapidly after pressurization proceeded higher rate for systems with the lower water saturation. Peak 21%, 41%, 60% saturation was 4.3 × 10–6, 1.44 1.7 10–6 mol/s, respectively. Three distinct stages were observed growth in porous media; rapid regime determined by enclathration reaction...
This paper presents the phase behavior of multicomponent gas hydrate systems formed from primarily methane with small amounts ethane and propane. Experimental conditions were typically in a pressure range between 1 6 MPa, temperature was 260 290 K. These have been investigated using variety techniques including microscopic observations, Raman spectroscopy, X-ray diffraction. techniques, used combination, allowed for measurement structure composition, while observing morphology crystals...
This study presents the influences of additional guest molecules such as C2H6, C3H8, and CO2 on methane hydrates regarding their thermal behavior. For this purpose, onset temperatures decomposition well enthalpies dissociation were determined for synthesized multicomponent gas in range 173−290 K at atmospheric pressure using a Calvet heat-flow calorimeter. Furthermore, structures compositions obtained X-ray diffraction Raman spectroscopy hydrate prediction program calculations. It is shown...
A LArge Reservoir Simulator (LARS) was equipped with an electrical resistivity tomography (ERT) array to monitor hydrate formation and dissociation experiments. During two experiments reaching 90 per cent bulk saturation, frequent measurements of the properties within sediment sample were performed. Subsequently, several common mixing rules, including different interpretations Archie's law, tested convert obtained distribution into spatial local saturation. It turned out that best results...
The LArge Reservoir Simulator (LARS) was developed to investigate various processes during gas hydrate formation and dissociation under simulated in situ conditions of relatively high pressure low temperature (close natural conditions). To monitor the spatial distribution mobility free phase generated dissociation, a cylindrical Electrical Resistivity Tomography (ERT) array implemented into LARS. ERT contains 375 electrodes, arranged 25 circular rings featuring 15 electrodes each. were...
Abstract The sequestration of industrially emitted CO 2 in gas hydrate reservoirs has been recently discussed as an option to reduce atmospheric greenhouse gas. This contains, despite much effort clean it, traces impurities such SO and NO . Here, we present results a pilot study on hydrates contaminated with 1 % or show the impact formation stability. Microscopic observations similar rates, but increase stability presence Laser Raman spectroscopy indicates strong enrichment liquid phase its...
In this study we present results of our investigations on simple CH4-hydrate and mixed hydrates during the initial steps hydrate formation process. situ Raman spectroscopy, microscopic observation in X-ray diffraction were used systematic studies. Although these techniques give only a limited view molecular level combined from experiments reported here indicate that labile cluster hypothesis can describe Specifically, guest molecules dissolve aqueous phase before they are encaged into single...
Abstract In 2012 the production of CH 4 from hydrate‐bearing sediments via CO 2 injection was conducted in framework Iġnik Sikumi Field Trial Alaska, USA. order to preserve injectivity by avoiding a formation hydrate near‐well region, mixture containing 77 mol% N and 23 chosen. The interpretation complex test results difficult, nature interaction between ‐CO initial could not be clarified. this study we present our experimental investigations simulating at different scales. We (1) situ Raman...
Natural gas hydrates are ice-like solids occurring worldwide on continental margins and in permafrost regions. Their high methane (CH4) content makes them a potential energy source, but also climate factor. Pressure temperature changes their environment may induce the decomposition of hydrates. Some hydrates, however, exhibit so-called self-preservation effect which delays process is not yet sufficiently understood. In present work, behavior simple mixed sI sII was studied via experiments (T...
CH 4 -C 3 H 8 mixed gas hydrates are widely distributed in deep-sea weakly-consolidated muddy sediments of the South China Sea, enriched with biological clastics like foraminifera-rich sand. However, role complex mineral composition mud and sand on formation these natural remains unclear. This study employed five from i.e., sand, a mixture three different samples, to reveal their effects hydrate formation. Gas were formed water constant-feed containing 96 mol% C . The process was...
Abstract Clathrate hydrates—also known as gas hydrates—are ice-like compounds consisting of and water molecules. They occur wherever elevated pressures low temperatures prevail; where enough hydrate-forming molecules are available. Therefore, natural hydrates at all active passive continental margins, in permafrost regions, some deep lakes, under unfavorable circumstances, also, pipelines. This article provides an overview the (thermodynamic) requirements various models for nucleation growth...