Within the frame of the project the project partners will develop a concept for the efficient and cost effective treatment of olive mill wastewater (OMW) in Mediterranean countries. A pilot plant will be constructed in Crete and the processed wastewater (WW) will be reused in a brickyard or in agriculture. Purification methods which are adapted to the regional climatic conditions and the composition of the WW have to be used for the WW treatment. After a technology comparison of purification methods used in the Mediterranean the existing procedures have to be optimised in order to ensure the reduction of the loads below specific limits under consideration of low investment and operating costs. The threshold values have to be determinate and established for the different reuses (industry and agriculture). In the frame of the project the partners will construct a treatment plant for an existing olive mill in the municipality of Mousouron/Crete. The actually occurring environmental problems by the untreated wastewater of the olive oil mills will be solved. The WW will be treated by "classical" aerobic and anaerobic in-plant treatment steps to reduce the organic contamination and, by the covering of the anaerobic treatment step, to produce biogas. A biological treatment by the Epuvalisation technology and a constructed wetland system, which are cost-effective possibilities for the water treatment, will be installed and compared with the common aerobic treatment. The treated water will be reused for irrigation or as a fertiliser in agriculture (improvement of soil structure) and for the direct plant production in the Epuvalisation treatment. The separated solid residuals will be used as biomass (valorisation of waste).

Scientific objectives:

1. Development of effective biological treatment technologies for OMW.
2. Optimisation of the effluent quality in relation to the afterwards utilisation in a brickyard and agriculture (definition of the necessary water quality).
3. Comparison (cost and effluent quality comparison) of aerobic in-plant treatment and biological systems (Epuvalisation and constructed wetlands).
4. Optimisation of the biogas production by anaerobic treatment of the olive oil wastewater (criteria: amount of produced biogas m³/d).

High priority should have be the reduction of the total amount of wastewater of the olive oil mill in the municipality of Mousouron. The effluent quality of the treated water will be adapted to the planned afterwards utilisation (brickyard, agriculture). This will help to reduce the fresh water demand of the brickyard. Therefore the required processed water from the olive oil mill has to fulfil the quality demand for the water utilisation for the use in the brick production. Because of the high temperatures in the process of the brick baking the water quality can be "lower" than for other WW reuse possibilities.