Centre for Research & Technology Hellas


Εργαστήριο Φυσικών Πόρων και Εναλλακτικών
Μορφών Ενέργειας

Chemical Process & Energy Resources Institute

Σ.Ι. Πάτσιος, Ε.Η. Παπαϊωάννου και Α.Ι. Καράμπελας: Long-term performance of a membrane bioreactor treating table olive processing wastewater (2015)

BACKGROUND: Table olive processing wastewater (TOPW) is a seriously polluting and difficult to treat effluent, characterized by widely fluctuating pH and salinity, as well as high concentrations of organic matter and polyphenols. This systematic long-term study in a laboratory-scale pilot demonstrates that membrane bioreactor (MBR) technology is effective in substantially bio-degrading TOPW. RESULTS: After implementation of an appropriate protocol of active biomass acclimatization/proliferation, the MBR pilot was operated for 6 months with real TOPW effluent, under various operating conditions. Total organic carbon (TOC) and total polyphenol (TPh) compounds removal efficiencies were very high with mean values 91.5 and 82.8%, respectively; nutrient (N and P) removal was also satisfactory. The membrane exhibited stable performance at moderate biomass concentration, with a tendency to deteriorate at higher biomass concentration. Fouled membrane permeability could be fully restored by implementing the usual chemical cleaning protocols. CONCLUSIONS: Despite the high percentage TOC and TPh removal, the MBR effluent requires final post-treatment to remove a yellowish tint and further reduce its organic content, depending on local discharge standards. The MBR can serve as the basic treatment processin anintegrated scheme for TOPWmanagement, which needs additional R&D to further develop and optimize. © 2015 Society of Chemical Industry