Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic Loading
In recent decades, olive oil consumption has almost tripled worldwide. Olive oil production is linked with the production of enormous amounts of olive mill wastewater, the main by-product derived from three-phase olive mills. Due to the environmental risks of olive mill wastewater disposal, the mana...
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MDPI AG
2022-03-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/12/6/2881 |
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| author | Konstantina Tsigkou Natalia Sivolapenko Michael Kornaros |
| author_facet | Konstantina Tsigkou Natalia Sivolapenko Michael Kornaros |
| author_sort | Konstantina Tsigkou |
| collection | DOAJ |
| description | In recent decades, olive oil consumption has almost tripled worldwide. Olive oil production is linked with the production of enormous amounts of olive mill wastewater, the main by-product derived from three-phase olive mills. Due to the environmental risks of olive mill wastewater disposal, the management and valorization of the specific waste stream is of great importance. This work focuses on the thermophilic dark fermentation of olive mill wastewater in batch reactors, targeting pH optimization and the organic loading effect. A series of experiments were performed, during which the organic load of the substrate remained at 40 g/L after dilution with tap water, and the pH was tested in the range of 4.5 to 7.5. The maximum yield in terms of produced hydrogen was obtained at pH 6.0, and the yields were 0.7 mol H<sub>2</sub>/mol glucose or 0.5 L H<sub>2</sub>/L<sub>reactor</sub>. At the same conditions, a reduction of 62% of the waste’s phenols was achieved. However, concerning the effect of organic loading at the optimized pH value (6.0), a further increase in the organic load minimized the hydrogen production, and the overall process was strongly inhibited. |
| first_indexed | 2024-03-09T20:09:43Z |
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| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-09T20:09:43Z |
| publishDate | 2022-03-01 |
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| spelling | doaj.art-70160b3f412b40a29d2e74987ca01d4f2023-11-24T00:20:43ZengMDPI AGApplied Sciences2076-34172022-03-01126288110.3390/app12062881Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic LoadingKonstantina Tsigkou0Natalia Sivolapenko1Michael Kornaros2Department of Chemical Engineering, University of Patras, 1 Karatheodori Str., University Campus, 26504 Patras, GreeceDepartment of Management, Economics and Industrial Engineering, Politecnico di Milano, Via Lambruschini 4/b, 20156 Milan, ItalyDepartment of Chemical Engineering, University of Patras, 1 Karatheodori Str., University Campus, 26504 Patras, GreeceIn recent decades, olive oil consumption has almost tripled worldwide. Olive oil production is linked with the production of enormous amounts of olive mill wastewater, the main by-product derived from three-phase olive mills. Due to the environmental risks of olive mill wastewater disposal, the management and valorization of the specific waste stream is of great importance. This work focuses on the thermophilic dark fermentation of olive mill wastewater in batch reactors, targeting pH optimization and the organic loading effect. A series of experiments were performed, during which the organic load of the substrate remained at 40 g/L after dilution with tap water, and the pH was tested in the range of 4.5 to 7.5. The maximum yield in terms of produced hydrogen was obtained at pH 6.0, and the yields were 0.7 mol H<sub>2</sub>/mol glucose or 0.5 L H<sub>2</sub>/L<sub>reactor</sub>. At the same conditions, a reduction of 62% of the waste’s phenols was achieved. However, concerning the effect of organic loading at the optimized pH value (6.0), a further increase in the organic load minimized the hydrogen production, and the overall process was strongly inhibited.https://www.mdpi.com/2076-3417/12/6/2881dark fermentationolive mill wastewaterthermophilic conditionspH effectorganic loading effecthydrogen yield |
| spellingShingle | Konstantina Tsigkou Natalia Sivolapenko Michael Kornaros Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic Loading Applied Sciences dark fermentation olive mill wastewater thermophilic conditions pH effect organic loading effect hydrogen yield |
| title | Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic Loading |
| title_full | Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic Loading |
| title_fullStr | Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic Loading |
| title_full_unstemmed | Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic Loading |
| title_short | Thermophilic Dark Fermentation of Olive Mill Wastewater in Batch Reactors: Effect of pH and Organic Loading |
| title_sort | thermophilic dark fermentation of olive mill wastewater in batch reactors effect of ph and organic loading |
| topic | dark fermentation olive mill wastewater thermophilic conditions pH effect organic loading effect hydrogen yield |
| url | https://www.mdpi.com/2076-3417/12/6/2881 |
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