Initial Investigation of the Solar Drying Method for the Drying of Olive Oil By-Products
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In this study, a greenhouse-type solar dryer was developed in order to demonstrate an olive oil by-product and agro-residue Managing System, which uses solar drying processes for the treatment of olive oil mill residues to decrease the high energy consumption of the drying operations, thus decreasing the environmental impact of these residues. The resulting by-products, once dried out, have a final application as fuel. The greenhouse, with a roof height of 3.5 m and total area of 150 m2, consisted of three 3.0 × 1.5 × 0.20 m concrete tanks, where the drying of olive pomace (two- and three-phase olive mills), leaves and biomass from pruning for the production of solid biofuels was examined. The two-phase olive mill by-products required more drying time than three-phase olive mill by-products due to higher moisture content. Moreover, the moisture rate was positively related to minimum relative humidity and the highest material and ambient temperature. Using free solar energy for drying olive oil by-products can be beneficial from the point of view of energy consumption and, consequently, the drying system cost. The main innovation of the process is using the most abundantly available energy source in Greece—and the Mediterranean basin generally—the sun.
KeywordsSolar drying Greenhouse Agro-industrial waste Olive oil by-products Moisture Combustion
This research has been co-funded by the European Union (European Regional Development Fund) and Greek national funds through the National Strategic Reference Framework (NSRF): Program “Development of Industrial Research and Technology (PAVET) 2013” (1359-ΒΕΤ-2013, Production of Organic Fertilizer and Biofuels from Olive Mill Wastes).
- 1.Hall, D.O., Rosillo-Calle, F., Williams, R.H., Woods, J.: Biomass for Energy: Supply Prospects. In: Johansson, T.B., Kelly, H., Reddy, A.K.N., Williams, R.H. (eds.) Renewable Energy, Sources for Fuels and Electricity, pp. 593–651. Island Press, Washington, DC (1993)Google Scholar
- 2.Goldemberg, J., Johanson, T.B.: World Energy Assessment. Overview 2004 Update, United Nation Development Programme, New York (2004)Google Scholar
- 6.Turkenburg. W.C.: Renewable Energy Technologies. UNDP/UN-DESA/WEC, pp. 219–224 (2000)Google Scholar
- 7.Van den Broek, R.: Sustainability of Biomass Electricity Systems, p. 216. Department of Science Technology & Society, Utrecht University, Utrecht (2000)Google Scholar
- 17.Alba, J., Hidalgo, F.J., Ruiz, M.A., Martínez, F., Moyano, M.J., Borja, R.: Elaboracion de aceite de oliva virgen. In: Barranco, D., Fernandez-Escobar, R., Rallo, L. (eds.) El Cultivo Del Olivo, pp. 551–588. Mundi-Prensa, Madrid (2001)Google Scholar
- 25.Kudra, T., Mujumdar, A.S.: Advanced Drying Technologies. Marcel Dekker, Inc., New York (2002)Google Scholar
- 31.Roux, N., Jung, D., Pannejon, J., Lemoine, C.: Modelling of the solar drying process Solia. In: Pierucci, S., Ferraris, G.B. (eds.) Proceeding of 20th European Symposium on Computer Aided Process Engineering (2010)Google Scholar
- 39.Ekechukwu, O.V.: Experimental Studies of Integral-Type Natural Circulation Solar-Energy Tropical Crop Dryers. Cranfield Institute of Technology, Cranfield (1987)Google Scholar