本研究旨在利用計算機輔助設計一組運用於化學迴路程序，100 kW等級之多階式循環流體化床系統。首先利用由拉-由拉雙相流方法於二維模擬中發展出多階式的篩板與降流管結構後，利用三維模擬方法將裝置轉換為可製作的規格品並進行細節調整。本研究在設計的過程中針對以往載氧體滯留時間不足以及燃料反應器中的氣體竄混至旋風分離器的問題進行了針對性的優化。藉由多階篩板結構解決大型氣體塊泡的生成與載氧體淘失之兩大問題，並且以對開式降流板設計，使載氧體在燃料反應器中的滯留時間大幅提升。而燃料反應器中的氣體竄混問題則藉由旋風分離器底部的特殊設計，使得進入燃料反應器中的載氧體自動在旋風分離器底部的降流管形成料封後得到解決。而以往的研究中極為困擾的旋風分離器設計問題亦使用Aspen Plus中的固體單元模組得到系統性的開發與設計。為了印證系統的可靠度，在顆粒流場模擬的輔助下，本研究製作了一組反應器之冷態模型，並且確認了系統運作的細節參數，最終製成了一組可以承受100 kW相當風量等級之多階式循環流體化床反應器冷態模型。
本研究利用冷態模型進行性能驗證的結果後發現，該系統可以利用調整旋風分離器底部降流管的形狀與長度，將載氧體總循環量控制於0至10 kg/min 之間，並且利用自身形成的料封將燃料反應器內的氣體洩漏量減少至3% 以下。而利用顆粒流場的模擬，可以確認當系統操作於150 kW之相當風量時仍然可以維持約6 kg/hr之載氧體淘失量。而冷模實驗的結果亦顯示了在多階式的燃料反應器運作的過程中，可以利用壓力響應來判定載氧體的流體化情形並作為自動化控制的重要依據。

The target of this study is to build up a 100 kW chemical looping process (CLP) via multi-stage circulating fluidized bed system with computer-aided design. At the first, the multi-stage sieve plate and downcomer structure are developed by the 2-D CFD euler-euler two-phase simulation method. After that, the device is converted into commercial specification for units by using 3-D simulation. In this study, the design procedure is focused on how to increase the retention time of the oxygen carrier (OC) and overcome the issue of gas leakage into cyclone from the fuel reactor (FR). The multi-stage sieve plate structure is a good arrangement to decrease the slug generation and OC elutriation. Based on the above design, the retention time of the OC in the FR is greatly improved by alternative downcomer on each stage. The gas leakage from the FR can be reduced by the special design at the downcomer of the cyclone, and the gas seal will automatically form while OC entering into the FR. Furthermore, the cyclone is designed systematically by using another commercial software, Aspen Plus. In order to test the reliability of the system, an experiment of the cold model reactor is built to confirm the detailed parameters of operation from the result of particle flow simulation. Finally, a multi-stage circulating fluidized bed reactor cold model has established and it could withstand the equivalent capacity of 100 kW CLP. The results of the cold model experiment show that the circulation rate of the OC can be controlled between 0 and 10 kg/min by adjusting the configuration of cyclone downcomer. Moreover, the gas leakage amount in FR is less than 3% while a gas seal formed in the cyclone downcomer. And only 6 kg/hr OC elutriation is found by the particle flow simulation while the system at equivalent capacity of 150 kW CLP condition. The results of the cold model experiment also show that the pressure response on each stage of FR can be used to determine the fluidization states of the OC and provide an important basis for automatic control setting.

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