Development of a novel low-temperature gasification technology that can produce fuel gases highly efficiently by intensifying the catalytic effects of metals

2020 Fiscal Year Final Research Report

• Project/Area Number: 18KK0408
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research (A))
• Allocation Type: Multi-year Fund
• Research Field: Reaction engineering/Process system
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Fushimi Chihiro 東京農工大学, 工学(系)研究科(研究院), 教授 (50451886)
• Project Period (FY): 2019 – 2020
• Keywords: 熱分解 / ガス化 / ダウナー反応器 / 流動層 / 気体燃焼製造

Outline of Final Research Achievements

Experiments of coal pyrolysis and gasification was conducted in a novel downer (i.e. co-current down flow) pyrolyzer and bubbling fluidized bed gasifier. The effect of non-porous graphite carbon particles preheated at 1173 K was investigated. Results show the non-porous carbon greatly suppress the emission of tar owing to the decomposition of aromatic hydrocarbons into coke. Results indicate the conversion ratio to gases increased as graphite carbon to coal (C/C) weight ratio increases. Results from diffuse reflectance FT-IR show slight increase of carboxylic -OH and C=O bonds on graphite carbon surfaces.
The reactivity of the carbon was: char >>> DC after gasification > DC after pyrolysis > graphite carbon.
H2O has higher reactivity than CO2 during char gasification. This is due to the fact that a larger amount of C-O is remaining on the char during gasification.

Free Research Field

化学エネルギー工学

Academic Significance and Societal Importance of the Research Achievements

炭素系資源のガス化によるガス燃料（主にH2とCO）の生成効率指標として冷ガス効率があるが、これまで熱力学的に低温で効率が上がることが示唆されていた。しかし、低温でのガス化では、反応初期に生成するタールの処理と、チャーの反応性が低いことが問題となっている。本研究では熱分解時に反応温度まで加熱した粒子を供給し、初期のタールの粒子への付着挙動やその付着炭素のガス化反応特性を初めて明らかにした。
ここで得られた知見は、炭素リサイクルの反応器として近年着目されているバイオマスや炭素系廃棄物（廃プラスチックや廃タイヤなど）の低温ガス化炉にもそのまま適用可能である。