Biomethanization

• Published in: International biodeterioration & biodegradation 1996, Vol.38 (3), p.145-153
• Main Authors: Fiestas Ros de Ursinos, J.A., Borja-Padilla, R.
• Format: Article
• Language: English
• ISSN: 0964-8305; 1879-0208
• DOI: 10.1016/S0964-8305(96)00043-1

Vegetation water in the olive constitutes 45–50% of the fruit, with a total content of 170kgm −3, of which 150kgm −3 are organic compounds (80% of these can be directly converted to methane). Anaerobic digestion of this waste yields methane with an average content of 37m 3m −3 of vegetation water and an energetic yield of 325KwH, of which 30% can be converted into electrical energy and 63% into calorific energy by the use of cogeneration processes. This is sufficient to cover the energy needs of both an olive oil production plant and an anaerobic reactor for the integral purification of wastewater. From an economic point of view, and taking into account the costs of electric (15ptsKwH −1) and calorific energy (3.2ptstherm −1), the intrinsic value of olive vegetation water would be 2148ptsm −3. For the optimization of this process, the following lines of research were investigated: (i) development of a biological process for the biodegradation of the phenolic compounds responsible for the inhibition of the biomethanization process; (ii) selection of the nature and the characteristics of an appropriate support for the immobilization of anaerobic bacteria; and (iii) development of a system and high density cellular reactor to obtain optimum conditions—hydraulic residence time, methane yield and efficiency for the purification process.