Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction Pretreatment
To reveal the effect of torrefaction pretreatment on pyrolysis and gasification reactivity of biomass, corn cob was first subjected to torrefaction pretreatment in a fixed-bed reactor at various reaction temperatures. The pyrolysis reactivity, kinetics, and gasification reactivity of torrefied corn...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-12-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/15/24/9277 |
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| author | Shengpeng Xia Anqing Zheng Kun Zhao Zengli Zhao Haibin Li |
| author_facet | Shengpeng Xia Anqing Zheng Kun Zhao Zengli Zhao Haibin Li |
| author_sort | Shengpeng Xia |
| collection | DOAJ |
| description | To reveal the effect of torrefaction pretreatment on pyrolysis and gasification reactivity of biomass, corn cob was first subjected to torrefaction pretreatment in a fixed-bed reactor at various reaction temperatures. The pyrolysis reactivity, kinetics, and gasification reactivity of torrefied corn cob were systematically assessed by various methods, proving that torrefaction pretreatment has a substantial influence on the physicochemical properties of corn cobs. The O/C and H/C molar ratios of corn cobs considerably drop with the increasing torrefaction temperature, and their higher heat-ing value (HHV) and energy density rise as well. It is found that torrefaction improves the pyrolysis reactivity of corn cobs because hemicellulose degradation is more severe than cellulose degradation during torrefaction, resulting in an increase in the percentage of cellulose in torrefied corn cobs. However, the severe depolymerization, polycondensation, and carbonization reaction during torre-faction of corn cobs at 280–300 °C can lead to a significant decline in the pyrolysis reactivity of corn cobs. Torrefaction pretreatment increases the pyrolysis activation energy of corn cobs, in addition to decreasing the char gasification reactivity of corn cob. The average char gasification reactivity of corn cobs drops when torrefaction severity increases. The passivation of active sites on the char surface may cause condensation and carbonation reactions of corn cobs during torrefaction. These findings provide new sights into the reasonable design of efficient torrefaction methods for appli-cation prior to pyrolysis and gasification of biomass. |
| first_indexed | 2024-03-09T16:58:13Z |
| format | Article |
| id | doaj.art-faedfad1ac8e4914ad3aad881f9a1f30 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-09T16:58:13Z |
| publishDate | 2022-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-faedfad1ac8e4914ad3aad881f9a1f302023-11-24T14:34:00ZengMDPI AGEnergies1996-10732022-12-011524927710.3390/en15249277Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction PretreatmentShengpeng Xia0Anqing Zheng1Kun Zhao2Zengli Zhao3Haibin Li4Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, ChinaGuangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, ChinaGuangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, ChinaGuangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, ChinaGuangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, ChinaTo reveal the effect of torrefaction pretreatment on pyrolysis and gasification reactivity of biomass, corn cob was first subjected to torrefaction pretreatment in a fixed-bed reactor at various reaction temperatures. The pyrolysis reactivity, kinetics, and gasification reactivity of torrefied corn cob were systematically assessed by various methods, proving that torrefaction pretreatment has a substantial influence on the physicochemical properties of corn cobs. The O/C and H/C molar ratios of corn cobs considerably drop with the increasing torrefaction temperature, and their higher heat-ing value (HHV) and energy density rise as well. It is found that torrefaction improves the pyrolysis reactivity of corn cobs because hemicellulose degradation is more severe than cellulose degradation during torrefaction, resulting in an increase in the percentage of cellulose in torrefied corn cobs. However, the severe depolymerization, polycondensation, and carbonization reaction during torre-faction of corn cobs at 280–300 °C can lead to a significant decline in the pyrolysis reactivity of corn cobs. Torrefaction pretreatment increases the pyrolysis activation energy of corn cobs, in addition to decreasing the char gasification reactivity of corn cob. The average char gasification reactivity of corn cobs drops when torrefaction severity increases. The passivation of active sites on the char surface may cause condensation and carbonation reactions of corn cobs during torrefaction. These findings provide new sights into the reasonable design of efficient torrefaction methods for appli-cation prior to pyrolysis and gasification of biomass.https://www.mdpi.com/1996-1073/15/24/9277corn cobstorrefactionpyrolysis reactivitygasification reactivitypyrolysis kinetics |
| spellingShingle | Shengpeng Xia Anqing Zheng Kun Zhao Zengli Zhao Haibin Li Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction Pretreatment Energies corn cobs torrefaction pyrolysis reactivity gasification reactivity pyrolysis kinetics |
| title | Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction Pretreatment |
| title_full | Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction Pretreatment |
| title_fullStr | Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction Pretreatment |
| title_full_unstemmed | Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction Pretreatment |
| title_short | Evaluation of Pyrolysis Reactivity, Kinetics, and Gasification Reactivity of Corn Cobs after Torrefaction Pretreatment |
| title_sort | evaluation of pyrolysis reactivity kinetics and gasification reactivity of corn cobs after torrefaction pretreatment |
| topic | corn cobs torrefaction pyrolysis reactivity gasification reactivity pyrolysis kinetics |
| url | https://www.mdpi.com/1996-1073/15/24/9277 |
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