[Biodegraded characteristics of MGP-wastewater by domestic and screened organisms]

Among 16 bacteria that were screened out from 5 activated sludge, S-2, Y-3, XH-3 and their mixed strains M-3 were selected to biodegrade MGP (Manufacture gas from petroleum)-wastewater. They can remove 38.4%-44.0% CODCr, 95.4%-97.0% hydroxybenzene and 47.1%-53.7% aromatic compound after 60 h treatment, but the removal rate of NH4(+)-N was only 14.0%-17.6%. About 77 toxic organic compounds were detected by GC/MS analysis, the aromatic compounds which had 3 rings and 4-6 rings can be biodegraded by the bacteria. The removal rate of CODCr, NH4(+)-N and extractable organic compound were improved 13.1%-22.9%, 18.4%-22.7% and 13.1%-18.1% respectively when glucose was added in the wastewater, and when ethanol was existing in the wastewater, the corresponding increase were 12.5%-21.2%, 29.7%-42.2% and 6.7%-7.7%. The total removal rates of aromatic compound were increased 17.7%-21.7%, 15.4%-21.2%. The screened strains can improve the biodegradation rate of MGP-wastewater.