Energy efficiency and environmental performance of bioethanol production from sweet sorghum stem based on life cycle analysis.
Life cycle analysis method was used to evaluate the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem in China. The scope covers three units, including plant cultivation, feedstock transport, and bioethanol conversion. Results show that the net energy ratio was 1.56 and the net energy gain was 8.37 MJ/L. Human toxicity was identified as the most significant negative environmental impact, followed by eutrophication and acidification. Steam generation in the bioethanol conversion unit contributed 82.28% and 48.26% to total human toxicity and acidification potential, respectively. Fertilizers loss from farmland represented 67.23% of total eutrophication potential. The results were significantly affected by the inventory allocation methods, vinasse reusing approaches, and feedstock yields. Reusing vinasse as fuel for steam generation and better cultivation practice to control fertilizer loss could significantly contribute to enhance the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem.
College of Environmental & Safety Engineering, Changzhou University, Changzhou 213164, China. Electronic address: wmxcau@163.com.
Mingxin
M
Wang
College of Environmental & Safety Engineering, Changzhou University, Changzhou 213164, China.
Yahui
Y
Chen
China Environmental Science Research Institute, Beijing 100012, China.
Xunfeng
X
Xia
College of Environmental & Safety Engineering, Changzhou University, Changzhou 213164, China.
Jun
J
Li
College of Environmental & Safety Engineering, Changzhou University, Changzhou 213164, China.
Jianguo
J
Liu
D000431:Ethanol / Q000378:metabolism*; D018547:Plant Stems / Q000378:metabolism*; D045868:Sorghum / Q000378:metabolism*
D000431:Ethanol
Bioethanol; Energy efficiency; Environmental performance; Life cycle assessment; Sweet sorghum stem