OPTIMIZATION OF FED-BATCH TYPE BIOSLURRY REACTOR FOR REMOVING PAHs CONTAMINATED ON MARINE SEDIMENTS

Abstract

Removal of PAHs contaminated on environments has been great concern due to its toxic, genotoxic and carcinogenic effects. Conditions for sequential operation of bioslurry reactor for bioremediation of dredged sediments contaminated by PAHs were established. Microbial consortium was inoculated into 30% (v/v) sediment slurry supplemented with 1% mixed form cyclodextrin. Electron transport system activity after inoculation was rapidly increased between 1 and 2 days and maintained when 1/5 or 1/10 of treated slurry was recycled after 2 or 3 days of batch incubation. Degradation activity was also high after part of 2 or 3 days incubated slurry was recycled. Therefore, 2 days of batch incubation and recycling 10% treated slurry were determined for sequential operation of slurry reactor. During the treatments, proportion of inoculated consortium was decreased due to the activation of natural flora by supplemented carbon sources, therefore, appropriate concentration of mixed form cyclodextrin for fed-batch type slurry reactor was examined and determined to 0.5% after 2nd treatment.