Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Design considerations for aerobic fixed-film microbiological remediation of contaminated waters

Thesis/Dissertation ·
OSTI ID:6416352

There is sufficient information available documenting that biodegradation of trace synthetic organic compounds in contaminated waters is a feasible remediation technique, however, many details of process design still need to be determined. In this study several design parameters were considered. These included evaluating the effect of seeding with adapted microorganisms on the acclimation time; determining what depth of material supporting the bacteria was required for removal of contaminants, and observing the effect of hydraulic loading rate on the removal efficiency of the contaminants by the bacteria. The study was conducted in the laboratory using fixed-film biological reactor columns. Pentachlorophenol (PCP), 2,4,6 trichlorophenol and 2,4 dichlorophenol were used as the test contaminants. Dechlorinated Philadelphia tap water was used as the source water. The concentrations of the contaminants added to the source ranged between 200 and 800 {mu}g/l, making them available as secondary carbon sources for the attached microorganisms. The columns were packed with Ottawa sand (20-30 mesh). Depths of sand ranging from one inch to two feet were used for individual columns. The columns were operated in a downflow mode and the hydraulic loading rates through the columns were varied from 0.5 gpm/ft{sup 2} to 3 gpm/ft{sup 2}. The data indicate that the phenomenon of trace organic removal by biodegradation can be divided into three different stages: acclimation, equilibrium removal and clogging. The removal of the background dissolved organic decreased with depth as a first order relationship, which has been observed several times previously in fixed-film biological treatment of wastewater. The removal of the contaminants was observed to be zero order.

Research Organization:
Drexel Univ., Philadelphia, PA (USA)
OSTI ID:
6416352
Country of Publication:
United States
Language:
English