| dc.description.abstract | A 3D solid state Green River Oil Shale kerogen model was built in this thesis through the following two steps: 1. a molecular nanocluster model of kerogen composed of seven molecules was built based on an adsorption method; 2. the molecular nanocluster model was further transformed into a solid state model based on molecular dynamics simulation method. Moreover, with this 3D solid state model, a porous solid state kerogen model was further proposed based on the formation mechanism of the nanopores in kerogen.
Based on the solid state 3D model of kerogen, some physical, chemical and mechanical properties of the kerogen, such as density, Young’s modulus, Poisson ratio, compressibility, bulk modulus and shear modulus, IR, Raman, 13C and 1H spectra were calculated using quantum chemistry or molecular dynamical simulation methods. The theoretical calculation results matched the reported experimental results very well. Moreover, based on the porous model of kerogen, the sorption isotherms of six alkane gas molecules from methane to hexane at 212oF were calculated and it was discovered that the adsorption could be described by Langmuir model very well. Two empirical equations were established to calculate the parameters of Langmuir model. All the theoretical calculation results matched the reported experimental results very well.
These proposed method established a way to study and understand the properties of kerogen theoretically which provides the opportunities to extract the parameters for hydraulic fracturing design and reservoir simulation based on computational chemistry methods. The developed methods in this thesis can be further applied for other kerogen samples and may find wild applications in implementing new techniques or improving existing methods for hydraulic fracturing and enhancing oil recovery for shale resources. | en_US |
