SELF-FERMENTATION: INNOVATIVE PRETREATMENT FOR USE HIGH CONCENTRATION OF OLIVE MILL WASTEWATER IN ANAEROBIC DIGESTION PLANT

摘要

This study aimed to evaluate the impact of self fermentation on methane production as biologicalrnpretreatment of olive mill wastewater (OMW). The self-fermentation was carried out at room temperature withoutrnmixing and at natural light cycle. The batch assays were performed at the influent substrate concentration of 36.7 grnVS/l (OMW 100%), 18,4 g VS/l (OMW 50%) and 9.2 g VS/l (OMW 25%). The methane production wasrnperformed at 37℃ in mixing condition. The results of methane production were compared with those obtainedrnusing untreated OMW . The results of this study showed that the self fermentation process is a very effectivernpretreatment to produce methane. Only the self-fermented samples have produced methane from undiluted OMWrnand a maximum cumulative methane production of 7583 ± 138 mlCH_4/L and a yield of 246 ± 10 mlCH_4/ gVS werernobtained. A yield increase of +13.5% at OMW dilution of 50% was also achieved as compared to untreated OMWrnresults. Interestingly, in the anaerobic digestion of untreated OMW, high hydrogen yields, with an average value ofrn46.8 ± 1.9 mlH_2/gVS, were obtained. Moreover a depletion around 20% v/v of polyphenols was recorded for all experimental set.