title: Investigation on up-flow anaerobic sludge fixed film (UASFF) reactor for treating low-strength bilge water of Caspian Sea ships.
abstract: BACKGROUND
  In order to meet the International Maritime Organization (IMO) objectives, the main purpose of this study was using the cheap and practical wastewater treatment system for low-strength bilge water of Caspian Sea ships; therefore, the low-strength bilge water of the Caspian Sea ships has been treated by up-flow anaerobic sludge fixed film (UASFF) reactor at the ambient temperature.
  
  
  RESULTS
  The reactor operated at two hydraulic retention times (HRTs) of 10 h and 8 h. The organic loading rates (OLR) ranged (0.12-0.6) g chemical oxygen demand (COD)/l.day. At the beginning of the experimental procedure, the sludge was immobilized on the surface of the support materials. After 10 days of batch feeding of the reactor with the wastewater as an acclimation period (with COD removal of 59%), the reactor operated continuously. At the end of the experiment, with the HRT of 8 h and OLR of 0.6 g COD/l.day, the COD and total suspended solid (TSS) removal efficiencies reached the amounts of 75% and 99%, respectively. In addition to the good features of the reactor in removing COD and TSS, the effluent oil concentration was significantly lower than the standard value (15 ppm) which has been laid down for the discharge of the bilge water from ships by the IMO.
  
  
  CONCLUSIONS
  The obtained data demonstrated that UASFF reactor is an appropriate system for treatment of a low-strength bilge water.
authors.affiliation: Department of Chemical Engineering, Semnan University, Semnan, Iran.
authors.forename: Seyyed Mohammad
authors.initials: SM
authors.lastname: Emadian
authors.affiliation: Department of Chemical Engineering, Babol University of Technology, Babol, Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Rahimnejad
authors.affiliation: Department of Chemical Engineering, Babol University of Technology, Babol, Iran.
authors.forename: Morteza
authors.initials: M
authors.lastname: Hosseini
authors.affiliation: Department of Chemical Engineering, Semnan University, Semnan, Iran.
authors.forename: Behnam
authors.initials: B
authors.lastname: Khoshandam
keywords: Anaerobic treatment; COD; Oil content; TSS; UASFF reactor; pH