著者

楊 翠芬 匂坂 正幸

出版者

日本LCA学会

雑誌

日本LCA学会誌 (ISSN:18802761)

巻号頁・発行日

vol.5, no.4, pp.501-509, 2009 (Released:2012-08-18)

参考文献数

20

被引用文献数

3 3

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Objective. Ethanol production from lignocellulosic biomass such as rice straw and wood are recently getting high attention. In this study, we evaluated energy consumption, CO2 emissions and cost of the ethanol production from rice straw by concentrated sulfuric acid hydrolysis throughout the life cycle and compared its results with gasoline. For the system boundary of the life cycle of bioethanol it is necessary to consider each process of the bioethanol production system including cultivation, harvesting, collection/transportation, fuel conversion, fuel transportation and fuel use. However, in this study, the cultivation process is not considered because we exclusively evaluate unused rice straw from agricultural residues. We considered harvesting, collection/transportation of rice straw, and conversion of ethanol, transportation of ethanol, lignin boiler, waste disposal, liquid waste treatment process and ethanol use. Beside the operation processes the construction of an ethanol plant, the rice straw collection/transportation vehicles, and the ethanol transportation vehicles were considered. Furthermore, we analyzed the influence of the rice straw cost and capacities of the bioethanol plant on the ethanol production cost.Results and Discussion. The energy consumption was estimated to be 728MJ, and CO2 emissions were estimated to be 39kg-CO2 per production of 1 GJ of ethanol. Energy input and CO2 emissions of the ethanol conversion process were the most aspects of the life cycle of ethanol. Bioethanol uses about 39% less energy and produces 51% less CO2 emissions than gasoline. Lignin residue combustion has a high potential for reducing energy consumption and CO2 emissions. The bioethanol cost was estimated to be 181 JPY/L. The rice straw cost and its conversion cost account for 68% and 30% of the total cost, respectively. In terms of cost, ethanol is not competitive with gasoline. However, if ethanol becomes tax-exempt from the gasoline tax, the ethanol price can become competitive for the end user.Conclusions. From the viewpoint of energy consumption and CO2 emissions, bioethanol is likely superior to gasoline. The system which utilizes lignin in a boiler and recovers heat effective increases the energy balance and reduces CO2 emissions. Since the rice straw collection/transportation cost accounts for a large part of the total cost in the ethanol production system, it is significant to make the price competitive. The development of low cost technologies to collect rice straw and ethanol conversion as well as a financial support system are needed.

著者

玄地 裕 楊 翠芬 匂坂 正幸

出版者

日本LCA学会

雑誌

日本LCA学会研究発表会講演要旨集

巻号頁・発行日

vol.2011, pp.182-182, 2011

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国産バイオ燃料の大幅な生産拡大を図るためには、食料や飼料等の既存用途に利用されている部分ではなく、未利用バイオマスの活用や耕作放棄地を活用した資源作物の生産に向けた取組を進めることが重要である。本研究では耕作放棄地の活用によるバイオ燃料生産の可能性・適用性について検討した。また、異なる原料由来のバイオ燃料生産システムにおける温室効果ガス排出量の推計、比較を行った。

著者

楊 翠芬 玄地 裕 匂坂 正幸

出版者

公益社団法人 土木学会

雑誌

土木学会論文集G(環境) (ISSN:21856648)

巻号頁・発行日

vol.68, no.6, pp.II_517-II_526, 2012 (Released:2013-02-13)

参考文献数

24

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本稿では耕作放棄地の活用によるバイオ燃料生産の可能性について検討した.また,耕作放棄地率が高い福島県をモデル地域とし,多収量米およびスイートソルガムを栽培して,バイオエタノールの生産・利用の最適化モデルを構築し,GHG排出量の少ないバイオエタノール生産・利用システムを検討した.結果としては,日本では農地への復元可能な耕作放棄地にて資源作物を栽培して約54万kLのエタノールが生産できる.また,福島県における水田・畑地への耕作放棄地にて多収量米およびスイートソルガムを栽培して年間約3.5万kLのエタノールが生産できる.バイオエタノールの使用により約3.2万t-CO2eq削減できる.また,多収量米よりスイートソルガムからエタノール生産のGHG排出削減効果が高かった.