New techniques in olive mill wastewater treatment (OMW)

Summary in the original language of the document

A new cost-effective system for complete exploitation of OMW is suggested, offering a viable solution to the problem of OMW disposal. Use of the proposed separation techniques prefiltration (PF), Ultrafiltration [UF], nanofiltration [NF], and reverse osmosis [RO]) produce byproducts that might include additional benefits. A pilot plant was developed in an olive mill operating in Achaia (Patras, Greece) during an olive harvesting season. Large volumes of OMW produced daily were treated systematically in a semibatch procedure to identify problems relevant to long-term behavior and reliability. The study showed that a fraction of pure water up to 75% can be recovered. Also fractions are isolated that contained concentrate nutritious and polyphenol content which can be further exploited in order to reduce the, indeed, high cost of the suggested treatment process. Finally, a feasibility-exploitation study was done to estimate if depreciation of the (indeed) expensive investment may occur in a short period of time. Together with the proposed method a synopis of commercially available techniques for the effective treatment of OMW is given. These techhnologies are based on biological, advanced oxidation, physicochemical and separation processes (composting, trickling filters, evaporation, oxidation, hydrolysis, co-digestion in a sewage treatment plant, production of solid fuels, etc).