Modeling volatile organic chemical removal by in situ soil mixing/hot-gas stripping

Conference · Fri Oct 01 04:00:00 EDT 1993 · Journal of Environmental Health; (United States)

OSTI ID:6064867

Wang, Congli; Gierke, J S; Schmunk, S W ^[1]; West, O R; Siegrist, R L ^[2]

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1. Michigan Technological Univ., Houghton, MI (United States). Dept. of Geological Engineering, Geology and Geophysics
2. Oak Ridge National Lab., TN (United States). Environmental Sciences Div.

In situ hot-gas stripping coupled with soil mixing is a promising technology for removing volatile organic chemicals and semivolatile organic chemicals from the unsaturated zone, especially for low-permeability soils. This process utilizes external energy to raise soil temperature, which enhances desorption and volatilization of the chemicals from the solid and aqueous phases. Mixing is used to increase soil permeability and enhance gas contact with contaminated soil and water. In this study, the authors developed and tested a mathematical model that simulates the in situ mixing/hot-gas injection process. The model was used to examine temperature effects on treatment efficiency for different gas injection schemes. The model predicts the temporal change in temperature, water saturation, exhaust gas flow rate, and gaseous-, aqueous-, and solid-phase concentrations of a volatile contaminant in the treatment zone of an in situ mixing process. The model accounts for first-order mass transfer between the gas and aqueous phases and vapor-solid and aqueous-solid sorption. Literature correlations are used in the model to predict temperature effects on Henry's constant, mass transfer rate, and gas-solid and liquid-solid partition coefficients. Results from laboratory experiments were used to calibrate the mass transfer rate. The calibrated model was used to analyze the removal efficiency of trichloroethylene was used to analyze the removal efficiency of trichloroethylene (TCE) from a clay soil for different injection conditions.

• OSTI ID: 6064867
• Report Number(s): CONF-9310166--
• Conference Information: Journal Name: Journal of Environmental Health; (United States) Journal Volume: 56:3
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540250* -- Environment
Terrestrial-- Site Resource & Use Studies-- (1990-)
CHLORINATED ALIPHATIC HYDROCARBONS
CLEANING
DECONTAMINATION
GROUND WATER
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROGEN COMPOUNDS
MANAGEMENT
MATERIALS RECOVERY
MATHEMATICAL MODELS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXYGEN COMPOUNDS
PROCESSING
REMEDIAL ACTION
SOILS
WASTE MANAGEMENT
WASTE PROCESSING
WATER