Highly-efficient power generation from biomass by combining chemical energy conversion and electrochemical reaction

Research Project

Project/Area Number	18K04826
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 27020:Chemical reaction and process system engineering-related
Research Institution	Kyoto University
Principal Investigator	Ashida Ryuichi 京都大学, 工学研究科, 講師 (80402965)
Co-Investigator(Kenkyū-buntansha)	河瀬元明京都大学, 工学研究科, 教授 (60231271)
Project Period (FY)	2018-04-01 – 2021-03-31
Project Status	Completed (Fiscal Year 2020)
Budget Amount *help	¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000) Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000) Fiscal Year 2019: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000) Fiscal Year 2018: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Keywords	高効率発電 / バイオマス / 化学エネルギー変換 / 電気化学反応
Outline of Final Research Achievements	We have proposed a novel highly-efficient power generation method in which biomass or low-rank coal reduces liquid phase metal ions such as VO2+ and subsequently electric power is generated by electrochemical oxidation of the reduced ions by O2 in air. It was shown that the reduction of VO2+ by Eucalyptus or a brown coal can proceed at lower than 250 °C and that by Eucalyptus can proceed at as low as 125 °C. The rate of the reaction between a brown coal and VO2+ has successfully been formulated and it was shown that the rector size of the proposed method can be comparable to the boiler generating the same electric power.
Academic Significance and Societal Importance of the Research Achievements	熱機関を利用した従来の発電方法によるバイオマス，褐炭からの発電効率は10～30 %程度と低く，バイオマス，褐炭発電が普及しない大きな一因となっている。本研究で開発した方法の理論発電効率は81 %で，種々の損失を考慮しても50 %以上の高効率を実現可能であり，バイオマス，褐炭発電の普及に貢献できる。また本法では，CO2の生成を伴うバイオマス，褐炭の酸化反応に空気を直接用いないことから，空気中の窒素ガスが排ガスのCO2に混入しない。よって，CO2の分離回収に余分なエネルギー，コストがかからない。さらに，電力需要変動に応じた柔軟な発電が可能であるというメリットも有する。