単粒子の原子炉,X線コンピュータトモグラフィー,計算モデリングを用いて,バイオマス小粒化による急速な溶解への影響を定量化
Meagan F Crowley1, Reinhard Seiser1, Mario Alejandro Sánchez Posada2
1National Renewable Energy Laboratory (NREL), Golden, Colorado 15013, United States.
まとめ
急速な熱分解のためのバイオマスの原料をペレル化すると,毛孔構造が著しく変化し,変換が遅くなり,チャールが増加します. バイオ燃料の生産を最適化するために,これらの微細構造の変化を正確な計算モデルで説明する必要があります.
科学分野:
- バイオマスの熱化学変換
- バイオ燃料の生産について
- リンゴセルロース原料の特性
背景:
- リンゴセルロース原料の孔構造と密度は,熱化学的変換中の粒子内輸送に不可欠です.
- バイオマスの微細構造は,種によって異なるし,ペレル化などの事前処理技術によって異なるため,熱分解の振る舞いに影響を及ぼします.
- ピロリシスの過程における形態学的変化は,毛孔構造,変換時間,および製品分布に影響します.
研究 の 目的:
- 整然とした松の原料と小粒状の松の原料の急速な Pyrolysis を包括的に比較するために.
- 粒子のスケール輸送現象と変換行動に対するペレル化の影響を調査する.
- 実験データとX線コンピューティングトモグラフィー (XCT) 画像を用いて粒子スケールモデルを検証する.
主な方法:
- 片粒子の素早く解熱する実験は,きれいにペレット化された松で実施した.
- アニゾトロプ的熱と質量輸送とCRECKメカニズム反応を組み込んだ粒子のスケールモデルの開発.
- 定量的な微細構造分析のためのX線コンピュータトモグラフィー (XCT) を使用した3Dイメージング.
主要な成果:
- ペレル化により,より密度が高く,浸透性が低い松の原料が生み出され,乾燥した松と比較して,より遅いピロリシスとより高い炭の収穫量をもたらしました.
- Pyrolytic変換は,カーポロシティーと透過性を増加させながら,曲率とアニソトロピーを減少させました.
- 粒子のモデリングは,精密なシミュレーションのためのダイナミックなアニゾトロプ的輸送の決定的な重要性を実証しました.
結論:
- ペレル化により,急速な熱分解中に生体質の変換行動が著しく変化する.
- 微細構造的属性,特に孔構造とアニソトロピーは,正確な熱溶解プロセス設計のための計算モデルに組み込まれなければなりません.
- これらの微細構造的効果を理解することは,リンゴセルロース原料からバイオ燃料と生化学製品の生産を最適化するために不可欠です.
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