Mass transfer and biodegradation of PAH compounds from coal tar. Quarterly technical report, January--March 1993

Technical Report · Thu Sep 01 04:00:00 EDT 1994

DOI:https://doi.org/10.2172/10178225· OSTI ID:10178225

Ramaswami, A; Ghoshal, S; Luthy, R G

This study examines the role of physico-chemical mass transfer processes on the rate of biotransformation of polycyclic aromatic hydrocarbon (PAH) compounds released from non-aqueous phase liquid (NAPL) coal tar present at residual saturation within a microporous medium. A simplified coupled dissolution-degradation model is developed that describes the concurrent mass transfer and biokinetic processes occurring in the system. Model results indicate that a dimensionless Damkohler number can be utilized to distinguish between systems that are mass transfer limited, and those that are limited by biological phenomena. The Damkohler number is estimated from independent laboratory experiments that measure the rates of aqueous phase dissolution and biodegradation of naphthalene from coal tar. Experimental data for Stroudsburg coal tar imbibed within 236 {mu}m diameter silica particles yield Damkohler numbers smaller than unity, indicating, for the particular system under study, that the overall rate of biotransformation of naphthalene is not limited by the mass transfer of naphthalene from coal tar to the bulk aqueous phase. There is a need for investigation of mass transfer for larger particles and/or other PAH compounds, and study of microbial rate-limiting phenomena including toxicity, inhibition and competitive substrate utilization.

• Research Organization: Carnegie-Mellon Univ., Pittsburgh, PA (United States). Dept. of Civil Engineering
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG22-90PC90303
• OSTI ID: 10178225
• Report Number(s): DOE/PC/90303--T6; ON: DE94017919
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600
BACTERIA
BIODEGRADATION
CHEMICAL REACTION KINETICS
COAL TAR
MASS TRANSFER
POLYCYCLIC AROMATIC HYDROCARBONS
PROGRESS REPORT
PROPERTIES AND COMPOSITION
SILICA