Olive mill wastewater controlled drying for material and water recovery

This work aims to bring a sustainable solution for the management of the hazardous olive mill wastewaters (OMWW) which are produced in large amounts in Mediterranean countries. The proposed strategy allows not only an energetic valorization but also the recovery of the contained water for possible reuse in agriculture. More precisely, the OMWW were firstly impregnated onto different biomasses, namely sawdust and wood chips. These biomasses were then dried in a convective drier and the evaporated water was condensed and recovered. The physico-chemical characterization of the so-obtained waters showed that they can be used in irrigation after their mixing with natural waters. As for the dried biomasses, they presented interesting mechanical and thermal properties which suggested making pellets out of them in order to get biofuels for pyrolysis processes. The resulting solid residue, in turn, could be valorized in agriculture as biofertilizer.