skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Solubilities of heavy fossil fuels in compressed gases

Thesis/Dissertation ·
OSTI ID:6729196

Design of processes for upgrading heavy fossil fuels such as coal-derived liquids, heavy petroleum fractions, tar sands, and shale oil, requires quantitative information for equilibrium properties of the fossil fuel in the presence of compressed light gases at elevated temperatures. Presented here are methods to predict and measure solubilities of heavy fossil fuels in compressed gases in the region ambient to 100 bar and 600 K. A molecular-thermodynamic model is used to predict heavy fossil-fuel solubilities. The heavy fuel is fractionated ina spinning-band column at low pressure and high reflux; each fraction is considered to be a pseudo-component. Each fraction is characterized by one vapor-pressure datum (obtained during fractionation), elemental analysis, and proton-NMR spectra (to determine aromaticity). Liquid-phase properties are obtained from the SWAP equation for vapor pressure and from a density correlation. Vapor-phase properties are obtained using the virial equation of state with virial coefficients from Kaul's correlation. The molecular-thermodynamic model has been used to establish a design-oriented computer program for calculating heavy, fossil-fuel solubility for general application in process design and, in particular, for isobaric condensation as a function of temperature as required for design of a continuous-flow heat exchanger. A total-vaporization technique is used to measure the solubilities of narrow-boiling, heavy fossil-fuel fractions in compressed gases. The solubility of a heavy fraction is determined from the volume of gas required to vaporize completely a small, measured mass of fossil-fuel sample. To test the molecular-thermodynamic model, the total-vaporization technique has been used to measure the solubilities of two Lurgi coal-tar fractions in compressed methane. Predicted and experimental solubilities agree well.

OSTI ID:
6729196
Resource Relation:
Other Information: Thesis (Ph. D.)
Country of Publication:
United States
Language:
English