生質物是可大規模使用的可再生能源之一。然而，直接使用生質物作為燃料會產生不利影響，包括燃燒效率低，以及煙氣路徑管線的腐蝕和結垢。在生質物熱轉化技術中，快速熱解技術因其加工速度快、轉化效率高、生物油產量大等優點，而成為一種很有前景的技術。計算流體動力學 (CFD) 已被證明是用於對複雜現象進行數值模擬的強大工具，包括涉及多相相互作用和化學反應的快速熱解。雙流體模型 (TFM) 框架在 Ansys Fluent 中提供低成本和有效的計算，它具有用戶友好的界面和嵌入式方程，具有用戶定義的函數 (UDF) 工具來修改或整合方程。熱解的綜合多步動力學方法是最有吸引力的熱解動力學機制，因為它能夠描述產物的產率和組成。 本研究分為三個步驟： (i) 根據文獻中的實驗和動力方法中，目前使用的組份，通過改變有機組份來修改熱解的綜合多步動力方法。實施適應的動力方法以研究管式反應器中快速熱解的能量動力學。 (ii) 通過合併反應步驟和去除無關緊要的反應步驟來簡化適應綜合動力方法。這種簡化將反應步驟從 25 個步驟減少到 16 個步驟，包括水分蒸發。實施該簡化方法以評估流化床熱解中生物顆粒尺寸和流化速度的影響。 (iii) 將簡化的動力方法與先進的次級和均相反應相結合，因為傳統次級反應的有機/焦油轉化速度比預期的要快。然後將該綜合動力方法用於流化床熱解的能量和可用能分析。所有提出的動力改進方法都經過實驗的驗證;Biomass is one of the renewable energy sources available on a large scale. However, the direct use of biomass as fuel promotes adversary effects, including low combustion efficiency, and corrosion and fouling along the flue gas path. Among the biomass thermal conversion technologies, fast pyrolysis is a promising technology due to its rapid process and high conversion efficiency with the maximum bio-oil product. Computational fluid dynamics (CFD) has proven to be a powerful tool for numerical simulations in complex phenomena, including fast pyrolysis, which involves multiphase interactions and chemical reactions. The two-fluid model (TFM) framework offers low-cost and effective computation in Ansys Fluent, which has a user-friendly interface and embedded equations with a user-defined function (UDF) facility to modify or integrate the equations. The comprehensive multistep kinetic scheme of pyrolysis is the most attractive pyrolysis kinetic mechanism due to the capability to describe both product yields and compositions. This study is divided into three steps: (i) Modify the comprehensive multistep kinetic scheme of pyrolysis by changing the organic species based on the experiment in literature and currently used species in the kinetic scheme. The adapted kinetic scheme was implemented for investigating the energy dynamics of fast pyrolysis in a tubular reactor. (ii) Simplify the adapted comprehensive kinetic scheme by combining the reaction steps and removing the insignificant reaction steps. This simplification reduced the reaction steps from 25 to 16 steps, including moisture evaporation. This simplified scheme was implemented to evaluate the effect of bioparticle size and fluidizing velocity in fluidized bed pyrolysis. (iii) Integrate the simplified kinetic scheme with the advanced secondary and homogeneous reactions since the conventional secondary reaction had a faster organic/tar conversion than expected. This integrated kinetic scheme was then employed for energy and exergy analyses of fluidized bed pyrolysis. All of the proposed kinetic modifications were validated with the experimental counterparts.
