本研究旨在利用計算顆粒流體力學CPFD模擬軟體，設計一套符合110 kWth產能規格的多階式流體化床，設計的過程需確保顆粒流動於反應器內部保持順暢。以先前100 kWth多階式流體化床之孔板設計的冷流模擬作為基礎案例，找出顆粒與氣體流動於反應器內應解決之問題，例如：模擬時間過長、氣體隔絕效果不佳、顆粒無法順利循環等。透過暖流模型之概念重新設計反應器結構，此方法可大幅減少流動模型切換至反應性模型時對於輸送現象上造成的誤差。
暖流模型設計過程應將整套迴路系統區分為各個單元，在固定各單元之氣體進料量的條件下，進行幾何尺寸之評估，最終將各單元進行連接，完成整套迴路之暖流模型。本研究之暖流模型符合各項標準，如：粒可順利循環於整套迴路內、氣體隔絕效果優異、模型計算速度快速等各項優點。以計算時間較快的暖流模型，作為反應性模型流動狀態之初步估算，對於顆粒流動無明顯差異，代表方法是可行且有效率的。
本研究之反應性模型可穩定操作於110 kWth規格下，平均載氧體循環量為2288.20 g/s約為136812g/min。且燃料甲烷已可完全反應為二氧化碳與水蒸氣。Fe3O4可於空氣反應器內氧化為Fe2O3。循環料封內的氣體已將兩大反應器之產出氣體進行隔絕。
經由產能增減測試，可穩定操作於90 kWth至130 kWth規格下，減產過程中所提供之空氣量不足以將前段時間產生之Fe3O4總量進行完全氧化，透過過量空氣20 %之操作，可確保Fe3O4於空氣反應器內完全氧化為Fe2O3。透過燃料反應器擋板，可大幅減顆粒淘失量，使得系統操作範圍更具彈性。擋板設計亦對於壓力量測有正面的影響，可清楚區別各垂直位置之壓力數值，對於監控壓力響應來判別實廠反應器內顆粒之流化情形有顯著的幫助。

The purpose of this research is to use the CPFD simulation software to design a multi-stage fluidized bed that meets the 110 kWth capacity specification. Take the cold model simulation of the orifice plate design of the 100 kWth multi-stage fluidized bed as a basic case to find out the problems that should be solved, such as: too large simulation time, poor gas isolation effect, and inability of particles smooth circulation and etc... By redesigning the reactor structure through the concept of the warm flow model, this method can greatly reduce the error caused by the transport phenomenon when the flow model is switched to the reactive model.
In the process of warm flow model design, the full loop system should be divided into individual units. The geometrical dimensions should be evaluated under the condition of fixing the gas feed volume of each unit. Finally, the units are connected to complete the warm flow model of the full loop. The warm flow model in this study meets various standards, such as: particles can circulate smoothly in the full loop system, excellent gas isolation effect, fast model calculation speed, etc... The warm flow model with faster calculation time is used as a preliminary estimation of the flow state of the reactive model. There is no significant difference in particle flow, and the method is feasible and efficient.
The reactivity model in this study can operate stably under the 110 kWth specification, and the average oxygen carrier circulation rate is 2288.20 g/s.that is about 136812 g/min The methane can be completely reacted into carbon dioxide and water vapor. Fe3O4 can be oxidized to Fe2O3 in an air reactor. The gas in the loop seal has isolated the produced gas from the two reactors.
Through the capacity increase and decrease test, it can operate stably under the specifications of 90 kWth to 130 kWth. The amount of air provided during the production reduction process is not enough to completely oxidize the total amount of Fe3O4 generated in the previous period. The operation of 20% excess air can ensure Fe3O4 is completely oxidized to Fe2O3 in the air reactor. Through the baffle of the fuel reactor, the particle elutriation loss can be greatly reduced, making the operating range of the system more flexible. The baffle design also has a positive effect on pressure measurement. It can clearly distinguish the pressure values of each vertical position. It is a significant help for monitoring the pressure response to determine the fluidization of particles in the reactor of the actual plant.

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