Abstract

Abstract During laboratory biodegradation of the oily liquid residue generated in normal ship operations, bilge waste, by an adapted native microbial community, bioemulsifier production and decrease in pH were observed. When the pH of the medium was modified by adding NaOH or buffering with Tris–HCl (pH 7.8), the greatest hydrocarbon reduction and biodegradation were found with NaOH treatment. With this treatment, total hydrocarbon removal and biodegradation efficiencies of, respectively, 97% and 86% for n-alkanes, 40% and 30% for total aliphatic hydrocarbons and 25% and 17% for total aromatic hydrocarbons were recorded after culture for 10 days. The emulsifying activity (quantified as emulsion index E24) was highest (60%) for neutralized treatment. For the three treatments the emulsifier activity was optimal at pH 6.5–7.5. Therefore, the culture medium should be neutralized to increase the rate of biodegradation and to minimize the residence time of the waste in a treatment unit.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.