Thermal variation of organic fluid properties and impact on thermal remediation feasibility

Abstract

Preliminary evaluations of the feasibility of thermal remediation techniques such as hot water flooding and steam flushing can be conducted with a knowledge of the influence of temperature on organic fluid properties such as interfacial tension, density, viscosity, solubility, vapor pressure, and Henry's constant. Relationships quantifying the effect of these fluid properties on organic removal and empirical equations for predicting the thermal variation of fluid properties are reviewed. Methods for measuring these properties are reviewed and applied to the characterization of perchloroethylene and a transformer oil. The importance of various removal mechanisms associated with thermal remediation is evaluated for these two fluids. Perchloroethylene solubilities increased by approximately 60% as temperature increased from 30°C to 90°C, suggesting that increased solubilization at higher temperatures would not be a significant removal mechanism. Viscosity and density reductions for both NAPLs were small, indicating that hydraulic displacement of NAPL would not be greatly enhanced with hot water or steam flushing. Interfacial tension decreases were not great enough to cause concem about downward remobilization of pools and residual zones of NAPLs. Capillary numbers for hot water flooding decreased for both NAPL, suggesting that hot water flooding would not enhance hydraulic removal of entrapped NAPL.