Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-Up
The start-up of two-stage, semi-continuous mesophilic anaerobic digestion (TSAD) of food waste is stabilized by altering the hydraulic retention time (HRT) and organic-loading rate (OLR). The volumetric biogas yield and composition are studied at OLR (0.25–0.50 gVS/L/d) and HRT (10, 20, 40 days) ini...
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MDPI AG
2022-11-01
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| Series: | Fermentation |
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| Online Access: | https://www.mdpi.com/2311-5637/8/11/620 |
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| author | Anmol Parajuli Aakash Khadka Lokesh Sapkota Anish Ghimire |
| author_facet | Anmol Parajuli Aakash Khadka Lokesh Sapkota Anish Ghimire |
| author_sort | Anmol Parajuli |
| collection | DOAJ |
| description | The start-up of two-stage, semi-continuous mesophilic anaerobic digestion (TSAD) of food waste is stabilized by altering the hydraulic retention time (HRT) and organic-loading rate (OLR). The volumetric biogas yield and composition are studied at OLR (0.25–0.50 gVS/L/d) and HRT (10, 20, 40 days) initiating at OLR 0.25 g VS/L/d and HRT of 20 and 40 days for the respective reactors. Methane (CH<sub>4</sub>) from the first stage of the two-staged reactor decreased from 18.20% to 0.06%, fostering hydrogen production in 44 days when the HRT was reduced from 20 to 10 days and OLR increased from 0.25 gVS/L/d to 0.50 gVS/L/d. During the alarming volatile fatty acids (VFA)/alkalinity ratio of 0.76, feeding to the second-stage reactor was halted until pH was restored to 7.00. The restoration of methanogens was evident by an increase in methane from 39.15% to 67.48%. A stable TSAD system produced 22.32 ± 4.16 NmL/gVS and 161.02 ± 17.72 NmL/gVS of yield in respective reactors. Thus, TSAD paves the path for multiple biofuels, i.e., H<sub>2</sub> and CH<sub>4</sub>. |
| first_indexed | 2024-03-09T19:05:43Z |
| format | Article |
| id | doaj.art-a9c68b0ca2cf4552932192606842e6a2 |
| institution | Directory Open Access Journal |
| issn | 2311-5637 |
| language | English |
| last_indexed | 2024-03-09T19:05:43Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fermentation |
| spelling | doaj.art-a9c68b0ca2cf4552932192606842e6a22023-11-24T04:38:23ZengMDPI AGFermentation2311-56372022-11-0181162010.3390/fermentation8110620Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-UpAnmol Parajuli0Aakash Khadka1Lokesh Sapkota2Anish Ghimire3Resource Recovery Research Group (Re3G), Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel 45200, NepalResource Recovery Research Group (Re3G), Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel 45200, NepalSoil Water and Air Testing Laboratories Pvt. Ltd., GPO 25752, Babarmahal, Kathmandu 44600, NepalResource Recovery Research Group (Re3G), Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel 45200, NepalThe start-up of two-stage, semi-continuous mesophilic anaerobic digestion (TSAD) of food waste is stabilized by altering the hydraulic retention time (HRT) and organic-loading rate (OLR). The volumetric biogas yield and composition are studied at OLR (0.25–0.50 gVS/L/d) and HRT (10, 20, 40 days) initiating at OLR 0.25 g VS/L/d and HRT of 20 and 40 days for the respective reactors. Methane (CH<sub>4</sub>) from the first stage of the two-staged reactor decreased from 18.20% to 0.06%, fostering hydrogen production in 44 days when the HRT was reduced from 20 to 10 days and OLR increased from 0.25 gVS/L/d to 0.50 gVS/L/d. During the alarming volatile fatty acids (VFA)/alkalinity ratio of 0.76, feeding to the second-stage reactor was halted until pH was restored to 7.00. The restoration of methanogens was evident by an increase in methane from 39.15% to 67.48%. A stable TSAD system produced 22.32 ± 4.16 NmL/gVS and 161.02 ± 17.72 NmL/gVS of yield in respective reactors. Thus, TSAD paves the path for multiple biofuels, i.e., H<sub>2</sub> and CH<sub>4</sub>.https://www.mdpi.com/2311-5637/8/11/620two-stage anaerobic digestionhydraulic retention timeorganic-loading ratebiogasfood waste valorizationfermentation |
| spellingShingle | Anmol Parajuli Aakash Khadka Lokesh Sapkota Anish Ghimire Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-Up Fermentation two-stage anaerobic digestion hydraulic retention time organic-loading rate biogas food waste valorization fermentation |
| title | Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-Up |
| title_full | Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-Up |
| title_fullStr | Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-Up |
| title_full_unstemmed | Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-Up |
| title_short | Effect of Hydraulic Retention Time and Organic-Loading Rate on Two-Staged, Semi-Continuous Mesophilic Anaerobic Digestion of Food Waste during Start-Up |
| title_sort | effect of hydraulic retention time and organic loading rate on two staged semi continuous mesophilic anaerobic digestion of food waste during start up |
| topic | two-stage anaerobic digestion hydraulic retention time organic-loading rate biogas food waste valorization fermentation |
| url | https://www.mdpi.com/2311-5637/8/11/620 |
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