Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Engineering
Simulation Of The Swelling Of High-Volatile Bituminous Coal During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong
Simulation Of The Swelling Of High-Volatile Bituminous Coal During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong
Faculty Publications
In this paper, a model is established to predict the swelling ratio of high-volatile bituminous coal during pyrolysis, based on the assumption that the structure of bubble distribution in the particle at the beginning of the plastic stage is a central bubble surrounded by many surrounding bubbles. The initial number and size of the bubbles when the particles become plastic are calculated by the pressure in the particle. The chemical percolation devolatilization (CPD) model is used to describe pyrolysis. The pyrolysis of eight types of high-volatile bituminous coals is simulated, and the results are compared with experimental results to verify …
Simulation Of The Evolution Of Pressure In A Lignite Particle During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong, Weishi Zhou
Simulation Of The Evolution Of Pressure In A Lignite Particle During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong, Weishi Zhou
Faculty Publications
The evolution of pressure in a lignite particle during pyrolysis was simulated on the basis of the gas motion equation in porous media and considering the Klinkenberg effect. The chemical percolation devolatilization (CPD) model was used to describe pyrolysis. The pore diameter in the particle is close to the average free path of volatile gas molecules; therefore, the solid phase restrains the movement of gas. Because flow out of the particle is restricted, the internal pressure rises. The internal pressure first increases and then decreases during pyrolysis, and the evolution is influenced by heating conditions. The pressure rise is larger …
Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, Ii. Characterization Of Pyrolysis Products By 13c Nmr, Gc/Ms, And Ftir, Thomas H. Fletcher, Ryan Gillis, Jacob Adams, Trent Hall
Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, Ii. Characterization Of Pyrolysis Products By 13c Nmr, Gc/Ms, And Ftir, Thomas H. Fletcher, Ryan Gillis, Jacob Adams, Trent Hall
Faculty Publications
This paper is Part II of a study of the chemical structural components of the organic matter of oil shale in the Green River formation. Three sections of a well-characterized oil shale core from the Utah Green River formation were demineralized, and the resulting kerogen was pyrolyzed at 10 °C/min in nitrogen at atmospheric pressure at temperatures up to 525 °C. The pyrolysis products (light gas, tar, and char) were analyzed using 13C NMR, GC/MS, and (FTIR). Pyrolysis yields of 80% (daf basis) were achieved at these conditions, with 60% daf tar yield at the highest temperature. The solid-state …
Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, I. Extracts, Mark S. Solum, Charles L. Mayne, Anita M. Orendt, Ronald J. Pugmire, Jacob Adams, Thomas H. Fletcher
Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, I. Extracts, Mark S. Solum, Charles L. Mayne, Anita M. Orendt, Ronald J. Pugmire, Jacob Adams, Thomas H. Fletcher
Faculty Publications
This paper is the first of two associated papers describing the structural details of three sections of an oil shale core taken at the Skyline 16 mine in the Utah Uinta Basin. Bitumen was extracted from the shale using methanol/dichloromethane. Kerogen was isolated from the shale, using a nine-step extraction procedure using HCl and HF. Bitumen samples from the three cores were analyzed using high-resolution 13C NMR liquid-state spectroscopy, showing carbon aromaticities of 7%−11%. Aliphatic carbons were dominated by methylene structures, with average aliphatic chain lengths of 24 carbons. The three parent shales and the demineralized kerogens were each …