Using waste from olive oil production

EU-funded scientists investigated the potential uses of waste produced by small olive oil producers to increase their competitiveness. Opportunities abound for use in the production of energy, as fertiliser and even for animal feed.

Olive mill waste (OMW) poses an important environmental problem, particularly in Mediterranean areas where olive oil is produced in large quantities. Dealing with that waste while remaining competitive is particularly challenging for numerous small local producers. In addition, Mediterranean producers are facing increasing competition from producers in other countries.

Recent efforts to implement activities making use of the residues have met with limited success largely due to a lack of requirements and guidelines for the needs of specific fields. The EU-funded project 'Adaptation of renewable energies technologies for the olive oil industry' (RESOLIVE) set out to exploit specific renewable energies based on OMW to reduce dependence of producers on centralised energy while increasing their competitiveness. The focus was three-pronged: gasification of OMW to obtain hydrogen, anaerobic digestion to obtain methane and recovery of organic matter in OMW for a variety of uses.

Scientists delivered a gas engine prototype demonstrating gasification of OMW for energy production. They generated extensive knowledge from laboratory analysis and research on anaerobic digestion to optimise biogas production. These two paths to production of renewable alternative energy from OMW utilised different waste streams to produce energy and heat, opening the path to a significant reduction in waste for disposal and important impact on competitiveness. The team also investigated the use of membrane filtration to recover organic compounds for combustion, for composting and use as fertiliser/soil conditioner in nurseries, and for use as animal feed.

Finally, RESOLIVE provided recommendations to enable cooperatives to operate throughout the year by producing energy from olive pits during harvest and from prunings during off-season periods. The technology is compatible with prunings form other sectors as well, making it of potential interest to wineries. Economic analyses and an assessment of permit requirements completed the study. Nineteen peer-reviewed articles were published during the running time of the project.

A wealth of potential uses of OMW together with economic analyses should make a significant impact on the competitiveness of olive oil producers. Enhanced competitiveness will provide welcome relief to Mediterranean countries in the depths of a severe economic crisis.

Related link:
http://cordis.europa.eu