Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewater
Iron metal (Fe0) materials enhance the performance of anaerobic digestion (AD) reactors to remove pollutants. Most research focused on the materials' mechanisms and effectiveness in enhancing AD. However, there is scant information on the biogas and sludge quality and quantity and the kinetics...
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| Format: | Article |
| Language: | English |
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Elsevier
2023-12-01
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| Series: | Case Studies in Chemical and Environmental Engineering |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666016423000828 |
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| author | Omari Bakari Karoli N. Njau Chicgoua Noubactep |
| author_facet | Omari Bakari Karoli N. Njau Chicgoua Noubactep |
| author_sort | Omari Bakari |
| collection | DOAJ |
| description | Iron metal (Fe0) materials enhance the performance of anaerobic digestion (AD) reactors to remove pollutants. Most research focused on the materials' mechanisms and effectiveness in enhancing AD. However, there is scant information on the biogas and sludge quality and quantity and the kinetics of generated methane (CH4) of biogas from the Fe0-aided AD of domestic wastewater (DW). The information is essential for AD reactors' management. This study characterizes the sludge and biogas from Fe0-aided AD of DW and predicts the CH4 yield using the Gompertz, Logistic, and Richard models to study the impact of Fe0 materials on the composition and generation of sludge and biogas. Bench-scale reactors containing DW were fed with Fe0 and operated for 53 days in a quiescent condition, at 24 ± 3 OC room temperature, at 7.3 initial pH value. Steel wool and iron scrap were used as Fe0 sources. A parallel experiment without Fe0 was performed as an operational reference. Results indicate that Fe0 significantly enriched most of the nutrients in sludges, produced well-settling sludge (sludge volume index ≤30), and enriched the CH4 of biogas by more than 12%. Furthermore, all the tested models exhibited good fitting (error <10%) in predicting CH4 production. Fe0-aided AD produced a sludge with the potential for application in agricultural land and increased the heating value of the biogas by enriching the CH4. More than 80% of particles generated from Fe0-aided AD of DW can be settled in sedimentation tanks designed at an overflow rate ≤40 m/d. Richard was the best model for predicting methane yield from Fe0-aided AD of DW (error <1.6%). |
| first_indexed | 2024-03-09T14:05:22Z |
| format | Article |
| id | doaj.art-f82145781dab475f960ccaf36277390c |
| institution | Directory Open Access Journal |
| issn | 2666-0164 |
| language | English |
| last_indexed | 2024-03-09T14:05:22Z |
| publishDate | 2023-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Case Studies in Chemical and Environmental Engineering |
| spelling | doaj.art-f82145781dab475f960ccaf36277390c2023-11-30T05:08:26ZengElsevierCase Studies in Chemical and Environmental Engineering2666-01642023-12-018100377Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewaterOmari Bakari0Karoli N. Njau1Chicgoua Noubactep2School of Materials, Energy, Water and Environmental Sciences, Nelson Mandela African Institution of Science and Technology (NM-AIST), Arusha, 23311, Tanzania; Corresponding author.School of Materials, Energy, Water and Environmental Sciences, Nelson Mandela African Institution of Science and Technology (NM-AIST), Arusha, 23311, TanzaniaCentre for Modern Indian Studies (CeMIS), University of Göttingen, Waldweg 26, D-37073, Göttingen, Germany; School of Earth Science and Engineering, Hohai University, Fo Cheng Xi Road 8, Nanjing, 211100, China; Faculty of Science and Technology, Campus of Banekane, Université des Montagnes, PO Box 208, Bangangté, CameroonIron metal (Fe0) materials enhance the performance of anaerobic digestion (AD) reactors to remove pollutants. Most research focused on the materials' mechanisms and effectiveness in enhancing AD. However, there is scant information on the biogas and sludge quality and quantity and the kinetics of generated methane (CH4) of biogas from the Fe0-aided AD of domestic wastewater (DW). The information is essential for AD reactors' management. This study characterizes the sludge and biogas from Fe0-aided AD of DW and predicts the CH4 yield using the Gompertz, Logistic, and Richard models to study the impact of Fe0 materials on the composition and generation of sludge and biogas. Bench-scale reactors containing DW were fed with Fe0 and operated for 53 days in a quiescent condition, at 24 ± 3 OC room temperature, at 7.3 initial pH value. Steel wool and iron scrap were used as Fe0 sources. A parallel experiment without Fe0 was performed as an operational reference. Results indicate that Fe0 significantly enriched most of the nutrients in sludges, produced well-settling sludge (sludge volume index ≤30), and enriched the CH4 of biogas by more than 12%. Furthermore, all the tested models exhibited good fitting (error <10%) in predicting CH4 production. Fe0-aided AD produced a sludge with the potential for application in agricultural land and increased the heating value of the biogas by enriching the CH4. More than 80% of particles generated from Fe0-aided AD of DW can be settled in sedimentation tanks designed at an overflow rate ≤40 m/d. Richard was the best model for predicting methane yield from Fe0-aided AD of DW (error <1.6%).http://www.sciencedirect.com/science/article/pii/S2666016423000828Anaerobic digestionBiogasDomestic wastewaterMetallic ironNutrientsSludge |
| spellingShingle | Omari Bakari Karoli N. Njau Chicgoua Noubactep Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewater Case Studies in Chemical and Environmental Engineering Anaerobic digestion Biogas Domestic wastewater Metallic iron Nutrients Sludge |
| title | Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewater |
| title_full | Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewater |
| title_fullStr | Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewater |
| title_full_unstemmed | Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewater |
| title_short | Effects of zero-valent iron on sludge and methane production in anaerobic digestion of domestic wastewater |
| title_sort | effects of zero valent iron on sludge and methane production in anaerobic digestion of domestic wastewater |
| topic | Anaerobic digestion Biogas Domestic wastewater Metallic iron Nutrients Sludge |
| url | http://www.sciencedirect.com/science/article/pii/S2666016423000828 |
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