scholarly journals MINERALOGY AND PORE-SIZE DISTRIBUTION OF FINE-GRAINED SEDIMENTARY ROCKS OF CARBONIFEROUS AND CRETACEOUS AGE, ZONGULDAK COAL BASIN, NW TURKEY

2016 ◽  
Author(s):  
Levent Bayram
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Sedimentary Rocks ◽  
Coal Basin ◽  
Fine Grained ◽  
Nw Turkey

scholarly journals Modelling Methane Hydrate Saturation in Pores: Capillary Inhibition Effects

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5627
Author(s):  
Maria De La Fuente ◽  
Jean Vaunat ◽  
Héctor Marín-Moreno
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Gas Hydrate ◽  
Hydrate Formation ◽  
Clapeyron Equation ◽  
Fine Grained ◽  
Chemical Potentials ◽  
Hydrate Saturation ◽  
Global Inventory

Experimental and field observations evidence the effects of capillarity in narrow pores on inhibiting the thermodynamic stability of gas hydrates and controlling their saturation. Thus, precise estimates of the gas hydrate global inventory require models that accurately describe gas hydrate stability in sediments. Here, an equilibrium model for hydrate formation in sediments that accounts for capillary inhibition effects is developed and validated against experimental data. Analogous to water freezing in pores, the model assumes that hydrate formation is controlled by the sediment pore size distribution and the balance of capillary forces at the hydrate–liquid interface. To build the formulation, we first derive the Clausius–Clapeyron equation for the thermodynamic equilibrium of methane and water chemical potentials. Then, this equation is combined with the van Genuchten’s capillary pressure to relate the thermodynamic properties of the system to the sediment pore size distribution and hydrate saturation. The model examines the influence of the sediment pore size distribution on hydrate saturation through the simulation of hydrate formation in sand, silt, and clays, under equilibrium conditions and without mass transfer limitations. The results show that at pressure–temperature conditions typically found in the seabed, capillary effects in very fine-grained clays can limit the maximum hydrate saturation below 20% of the host sediment porosity.

Measurement and estimation of pore shrinkage and pore distribution in a clayey till during soil-water characteristic curve tests

2001 ◽  
Vol 38 (4) ◽  
pp. 741-754 ◽  
Author(s):  
Paul H Simms ◽  
Ernest K Yanful
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Soil Water ◽  
Mine Waste ◽  
Characteristic Curve ◽  
Landfill Liners ◽  
Soil Water Characteristic Curve ◽  
Fine Grained ◽  
In Series

The soil-water characteristic curve (SWCC) of fine-grained soils is usually determined experimentally. In many applications, such as design of mine waste covers and landfill liners, the unsaturated permeability function, k(h), is often derived theoretically from the measured SWCC. Implicit in these derivations is the transformation of the SWCC to a pore-size distribution (PSD), typically assumed to be constant and mono-modal. PSDs of a clayey till compacted at various water contents were measured after compaction, after flexible-wall permeability testing, and during and after SWCC tests. The measurements show that the PSD changes significantly during permeability and SWCC testing. A method is advanced for predicting the observed changes in PSD during SWCC testing. PSDs are determined for soil samples subjected to the highest and lowest suctions applied during the SWCC test. The measured PSDs are transformed to account for pore trapping; the transform assumes that flow occurs through two sets of randomly distributed pores in series. To model pore shrinkage, the pores are idealized as elastic cylinders. PSDs measured after different suction applications in the SWCC tests are compared with predictions of the shrinkage model. The method can also be used to predict the SWCC. Measured and predicted values are compared.Key words: landfill liners, mine waste covers, soil-water characteristic curve, pore-size distribution.

pyGAPS: A Python-Based Framework for Adsorption Isotherm Processing and Material Characterisation

2019 ◽  
Author(s):  
Paul Iacomi ◽  
Philip L. Llewellyn
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Surface Area ◽  
Isosteric Heat ◽  
Material Characterisation ◽  
Mixture Adsorption ◽  
Surface Energetics ◽  
Adsorption Processing ◽  
User Friendly

Material characterisation through adsorption is a widely-used laboratory technique. The isotherms obtained through volumetric or gravimetric experiments impart insight through their features but can also be analysed to determine material characteristics such as specific surface area, pore size distribution, surface energetics, or used for predicting mixture adsorption. The pyGAPS (python General Adsorption Processing Suite) framework was developed to address the need for high-throughput processing of such adsorption data, independent of the origin, while also being capable of presenting individual results in a user-friendly manner. It contains many common characterisation methods such as: BET and Langmuir surface area, t and α plots, pore size distribution calculations (BJH, Dollimore-Heal, Horvath-Kawazoe, DFT/NLDFT kernel fitting), isosteric heat calculations, IAST calculations, isotherm modelling and more, as well as the ability to import and store data from Excel, CSV, JSON and sqlite databases. In this work, a description of the capabilities of pyGAPS is presented. The code is then be used in two case studies: a routine characterisation of a UiO-66(Zr) sample and in the processing of an adsorption dataset of a commercial carbon (Takeda 5A) for applications in gas separation.

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