Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken design
In this research, organic waste was subjected to hydrothermal carbonization (HTC) using faecal sludge as the water source. HTC is a sustainable method for converting organic waste into valuable hydrochar. However, the use of portable water as a reaction medium in HTC is environmentally unsustainable...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2024-04-01
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| Series: | Environmental Challenges |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2667010024000660 |
| _version_ | 1797226636338266112 |
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| author | Gloria Amenyeku Samuel Jerry Cobbina Wilhemina Asare Godfred Kwesi Teye |
| author_facet | Gloria Amenyeku Samuel Jerry Cobbina Wilhemina Asare Godfred Kwesi Teye |
| author_sort | Gloria Amenyeku |
| collection | DOAJ |
| description | In this research, organic waste was subjected to hydrothermal carbonization (HTC) using faecal sludge as the water source. HTC is a sustainable method for converting organic waste into valuable hydrochar. However, the use of portable water as a reaction medium in HTC is environmentally unsustainable and increases operational costs. The aim of this study was to optimize HTC operating parameters such as residence time, temperature, and biomass to water (BTW) ratio for maximizing both higher heating value (HHV) and hydrochar yield and also to determine the effects of these operating parameters on the hydrochar properties. This study utilized a Box Behnken design within the response surface methodology to identify optimal HTC conditions. Temperature was varied between 180 and 250 °C, residence time between 30 min and 120 min, and BTW ratio between 1 and 10. Volatile matter percentage was reduced in the hydrochar compared to that of the feedstock. A progressive rise in carbon percentage and a decline in oxygen percentage were observed with increasing temperatures. Temperature and residence time were the most significant factors affecting HHV, on the other hand, temperature and BTW ratio were the most significant factors that affected hydrochar yield. Numerical optimization of the factors revealed that a maximum HHV of 28.409 MJ/kg was obtained at 250 °C, 116 min, and a 1:9 BTW ratio, while an ideal hydrochar yield of 57.491% was obtained at 242 °C, 95 min and a BTW ratio of 1:9. This study highlights the environmental sustainability of utilizing faecal sludge as a water source in HTC, presenting a promising possibility for transforming organic waste into valuable hydrochar while addressing concerns related to water use. |
| first_indexed | 2024-04-24T14:28:03Z |
| format | Article |
| id | doaj.art-8b78f390c517420685b2e31b5880e527 |
| institution | Directory Open Access Journal |
| issn | 2667-0100 |
| language | English |
| last_indexed | 2024-04-24T14:28:03Z |
| publishDate | 2024-04-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Environmental Challenges |
| spelling | doaj.art-8b78f390c517420685b2e31b5880e5272024-04-03T04:27:34ZengElsevierEnvironmental Challenges2667-01002024-04-0115100900Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken designGloria Amenyeku0Samuel Jerry Cobbina1Wilhemina Asare2Godfred Kwesi Teye3West African Centre for Water, Irrigation and Sustainable Agriculture (WACWISA) Government of Ghana and World Bank through the African Centre's of Excellence for Development Impact initiative, University for Development Studies, Tamale, Ghana; Department of Environment and Sustainability Sciences, Faculty of Natural Resources and Environment, University for Development Studies, Tamale, Ghana; Corresponding author at: West African Centre for Water, Irrigation and Sustainable Agriculture (WACWISA) Government of Ghana and World Bank through the African Centre's of Excellence for Development Impact initiative, University for Development Studies, Tamale, Ghana.West African Centre for Water, Irrigation and Sustainable Agriculture (WACWISA) Government of Ghana and World Bank through the African Centre's of Excellence for Development Impact initiative, University for Development Studies, Tamale, Ghana; Department of Environment and Sustainability Sciences, Faculty of Natural Resources and Environment, University for Development Studies, Tamale, GhanaDepartment of Environment and Sustainability Sciences, Faculty of Natural Resources and Environment, University for Development Studies, Tamale, GhanaCentre for Climate Change and Sustainability Studies, University of Ghana, Legon, Accra, Ghana; Africa Environmental Sanitation Consult, Madina, Accra, GhanaIn this research, organic waste was subjected to hydrothermal carbonization (HTC) using faecal sludge as the water source. HTC is a sustainable method for converting organic waste into valuable hydrochar. However, the use of portable water as a reaction medium in HTC is environmentally unsustainable and increases operational costs. The aim of this study was to optimize HTC operating parameters such as residence time, temperature, and biomass to water (BTW) ratio for maximizing both higher heating value (HHV) and hydrochar yield and also to determine the effects of these operating parameters on the hydrochar properties. This study utilized a Box Behnken design within the response surface methodology to identify optimal HTC conditions. Temperature was varied between 180 and 250 °C, residence time between 30 min and 120 min, and BTW ratio between 1 and 10. Volatile matter percentage was reduced in the hydrochar compared to that of the feedstock. A progressive rise in carbon percentage and a decline in oxygen percentage were observed with increasing temperatures. Temperature and residence time were the most significant factors affecting HHV, on the other hand, temperature and BTW ratio were the most significant factors that affected hydrochar yield. Numerical optimization of the factors revealed that a maximum HHV of 28.409 MJ/kg was obtained at 250 °C, 116 min, and a 1:9 BTW ratio, while an ideal hydrochar yield of 57.491% was obtained at 242 °C, 95 min and a BTW ratio of 1:9. This study highlights the environmental sustainability of utilizing faecal sludge as a water source in HTC, presenting a promising possibility for transforming organic waste into valuable hydrochar while addressing concerns related to water use.http://www.sciencedirect.com/science/article/pii/S2667010024000660Faecal sludgeOrganic wasteHydrocharHydrothermal carbonizationBox Behnken designBiomass to water ratio (BTW) |
| spellingShingle | Gloria Amenyeku Samuel Jerry Cobbina Wilhemina Asare Godfred Kwesi Teye Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken design Environmental Challenges Faecal sludge Organic waste Hydrochar Hydrothermal carbonization Box Behnken design Biomass to water ratio (BTW) |
| title | Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken design |
| title_full | Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken design |
| title_fullStr | Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken design |
| title_full_unstemmed | Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken design |
| title_short | Hydrothermal carbonization of organic waste using faecal sludge as a water source: Response surface methodology-Box Behnken design |
| title_sort | hydrothermal carbonization of organic waste using faecal sludge as a water source response surface methodology box behnken design |
| topic | Faecal sludge Organic waste Hydrochar Hydrothermal carbonization Box Behnken design Biomass to water ratio (BTW) |
| url | http://www.sciencedirect.com/science/article/pii/S2667010024000660 |
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