title: Characterization of oily sludge from a refinery and biodegradability assessment using various hydrocarbon degrading strains and reconstituted consortia.
abstract: Oily sludge obtained from a refinery in India contained 10-11% oil associated with fine particulates. Along with Fe, Ca and Mg various toxic elements were associated with the sludge solids (Pb, Mn, Cu, Zn, As, Bi, Cd, Cr, Co, Ni and V). The oil contained 41-56% asphaltenes and the maltenes comprised of 49 ± 4%, 42 ± 2% and 4 ± 2%, aliphatic, aromatic and polar fractions, respectively. Biodegradation studies with the maltene fraction of oil provided as sole substrate revealed higher degradation by various 3-5 membered reconstituted consortia compared to pure bacterial strains and up to 42 ± 8% degradation could be achieved over 30 days. In contrast, over the same period up to 71.5 ± 2% oil degradation could be achieved using dried oily sludge (15% w/v) as sole substrate. Significant biodegradation observed in the un-inoculated controls indicated the presence of indigenous microorganisms in oily sludge. However, large variability in oil degradation was observed in the un-inoculated controls. Greater biodegradation of the maltene fraction led to significant enrichment of asphaltenes in residual oil associated with the sludge.
authors.affiliation: Centre for Environmental Science and Engineering, Indian Institute of Technology, Bombay, Powai, Mumbai 400 076, India.
authors.forename: Jublee
authors.initials: J
authors.lastname: Jasmine
authors.affiliation: Centre for Environmental Science and Engineering, Indian Institute of Technology, Bombay, Powai, Mumbai 400 076, India. Electronic address: mitras@iitb.ac.in.
authors.forename: Suparna
authors.initials: S
authors.lastname: Mukherji
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D006838:Hydrocarbons / Q000378:metabolism*; D007194:India; D007220:Industrial Waste / Q000032:analysis*; D059013:Microbial Consortia / Q000502:physiology*; D009821:Oils / Q000032:analysis
chemical_list: D006838:Hydrocarbons; D007220:Industrial Waste; D009821:Oils
keywords: Asphaltenes; Biodegradation; Heavy metals; Indigenous microorganisms; Microbial consortia; Oily sludge