Demonstration of bioaugmentation in a fluidized-bed process treating 1-naphthylamine

The feasibility of using a fluidized-bed reactor with bioaugmentation to treat low-strength wastewater or slightly contaminated groundwater was evaluated. Tap water spiked with 1.6 to 12.6 mg/L of 1-naphthylamine was treated in a fluidized-bed reactor with a hydraulic retention time of 6.2 to 13.3 h. With conventional operation, the reactor was unable to maintain consistent-removal because of cell washout. Continuous removal efficiency was greater than 90% using bioaugmentation through periodic addition of acclimated cells from an off-line enricher-reactor. The concept demonstrated by this research presents an alternative for biological treatment of wastes (dilute wastewaters and contaminated groundwater) which are not normally considered good candidates for biological treatment. (C) 1997 Elsevier Science Ltd.