title: Airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 for treatment of lubricants in wastewater.
abstract: An internal loop airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 was applied for the removal of automotive lubricants from emulsified wastewater. The chitosan-immobilized bacteria had higher lubricant removal efficiency than free and killed-immobilized cells because they were able to sorp and degrade the lubricants simultaneously. In a semi-continuous batch experiment, the immobilized bacteria were able to remove 80-90% of the 200 mg L(-1) total petroleum hydrocarbons (TPH) from both synthetic and carwash wastewater. The internal loop airlift bioreactor, containing 4 g L(-1) immobilized bacteria, was later designed and operated at 2.0 h HRT (hydraulic retention time) for over 70 days. At a steady state, the reactor continuously removed 85±5% TPH and 73±11% chemical oxygen demand (COD) from the carwash wastewater with 25-200 mg L(-1) amended lubricant. The internal loop airlift reactor's simple operation and high stability demonstrate its high potential for use in treating lubricants in emulsified wastewater from carwashes and other industries.
authors.affiliation: International Postgraduate Programs in Environmental Management, Graduate School, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Nichakorn
authors.initials: N
authors.lastname: Khondee
authors.forename: Sitti
authors.initials: S
authors.lastname: Tathong
authors.forename: Onruthai
authors.initials: O
authors.lastname: Pinyakong
authors.forename: Sorawit
authors.initials: S
authors.lastname: Powtongsook
authors.forename: Thawach
authors.initials: T
authors.lastname: Chatchupong
authors.forename: Chalermchai
authors.initials: C
authors.lastname: Ruangchainikom
authors.forename: Ekawan
authors.initials: E
authors.lastname: Luepromchai
mesh_terms: D000042:Absorption; D001673:Biodegradation, Environmental; D019149:Bioreactors; D048271:Chitosan / Q000737:chemistry*; D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D004867:Equipment Design; D005410:Flame Ionization; D054327:Lubricants / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000737:chemistry; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D042301:Sphingomonadaceae / Q000737:chemistry* / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D054327:Lubricants; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D048271:Chitosan; D010100:Oxygen