"The EU is the most important producer of olives in the world, from 2001-2007, 2,2 million tonnes of olive oil were produced in about 12.000 olive mills, which accounts for the 80% of the world production. These producers are mainly SMEs placed in the basin of the Mediterranean Sea, being Spain, Italy and Greece the biggest producers. Olive oil consumption is growing worldwide thanks to the acknowledgement of its benefits on health. Although the EU is the main olive oil consumer, the demand in countries like USA and Syria has increased significantly in recent years. On the other hand, non-European countries like Turkey, Syria and Tunisia enter the market and harden competition, threatening EU producers’ dominant position. Besides the market expansion, the olive oil sector in the EU will have to solve some long-standing environmental problems to keep its predominant situation. During the olive processing, large amounts of highly pollutant liquid wastes are generated. This poses serious problems to olive oil mills since waste management involves additional costs and logistical problems, especially for the SMEs. About 50 litres of drinkable water are required to was 100 k of olives. Hence, an enormous amount of drinkable water in Mediterranean countries is consumed by this process (about 5 billions of litres a year). Such huge amount of water is mostly required in rural areas which, in contrast, very often exhibit serious shortage of water. The main objective of ALGATEC project is the treatment and reuse of WW generated in small olive oil mills, with high pollutant content, by means of an affordable and compact photobioreactor using microalgae, capable to recover and recycle the majority of the drinkable water used in the process of olives washing. Furthermore, their problem of the disposal of wastewater will be reduced because the reutilisation of the WW will diminish the overall volume of wastewater, with both economical and environmental benefits."