TY - JOUR
T1 - Torrefaction performance and energy usage of biomass wastes and their correlations with torrefaction severity index
AU - Zhang, Congyu
AU - Ho, Shih Hsin
AU - Chen, Wei Hsin
AU - Xie, Youping
AU - Liu, Zhenquan
AU - Chang, Jo Shu
N1 - Funding Information:
This work was supported by the State Key Laboratory of Urban Water Resource and Environment (Harbin Institute of Technology) (No. 2016TS07 ) and the Project of Thousand Youth Talents. The authors also acknowledge the financial support of the Ministry of Science and Technology, Taiwan, ROC , under the grant number MOST 106-2923-E-006-002-MY3 for this research.
Funding Information:
This work was supported by the State Key Laboratory of Urban Water Resource and Environment (Harbin Institute of Technology) (No. 2016TS07) and the Project of Thousand Youth Talents. The authors also acknowledge the financial support of the Ministry of Science and Technology, Taiwan, ROC, under the grant number MOST 106-2923-E-006-002-MY3 for this research.
Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/6/15
Y1 - 2018/6/15
N2 - Weight loss has been suggested as an important indicator of torrefaction severity for describing the performance of this thermal pretreatment process. The present study establishes a correlation of torrefaction performance, severity, and energy usage for the applications of this pretreatment for solid fuel (biochar) production. Three different biomass wastes, namely, spent coffee grounds, Chinese medicine residue, and microalga residue, have been torrefied in nitrogen at a temperature range of 200–300 °C for 15–60 min to produce biochars. Their properties such as the enhancement factor of higher heating value, energy yield, decarbonization, dehydrogenation, deoxygenation, and atomic O/C and H/C ratios have been investigated. The obtained results indicate that the introduced dimensionless parameter (the torrefaction severity index in terms of the weight loss of biomass) correlates sufficiently with the biochar properties; the exception is the O/C ratio as a consequence of the intrinsic difference in components between the utilized wastes. A new parameter (the upgrading energy index) was also defined to account for the energy efficiency of the torrefaction system. This index follows a decreasing trend with increasing torrefaction severity index. This shows that biochar quality or heating value is intensified at a higher torrefaction severity; however, the energy efficiency is lowered.
AB - Weight loss has been suggested as an important indicator of torrefaction severity for describing the performance of this thermal pretreatment process. The present study establishes a correlation of torrefaction performance, severity, and energy usage for the applications of this pretreatment for solid fuel (biochar) production. Three different biomass wastes, namely, spent coffee grounds, Chinese medicine residue, and microalga residue, have been torrefied in nitrogen at a temperature range of 200–300 °C for 15–60 min to produce biochars. Their properties such as the enhancement factor of higher heating value, energy yield, decarbonization, dehydrogenation, deoxygenation, and atomic O/C and H/C ratios have been investigated. The obtained results indicate that the introduced dimensionless parameter (the torrefaction severity index in terms of the weight loss of biomass) correlates sufficiently with the biochar properties; the exception is the O/C ratio as a consequence of the intrinsic difference in components between the utilized wastes. A new parameter (the upgrading energy index) was also defined to account for the energy efficiency of the torrefaction system. This index follows a decreasing trend with increasing torrefaction severity index. This shows that biochar quality or heating value is intensified at a higher torrefaction severity; however, the energy efficiency is lowered.
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U2 - 10.1016/j.apenergy.2018.03.129
DO - 10.1016/j.apenergy.2018.03.129
M3 - Article
AN - SCOPUS:85044618260
VL - 220
SP - 598
EP - 604
JO - Applied Energy
JF - Applied Energy
SN - 0306-2619
ER -