粉煤進料槽排放速率之研究

The Study of Pulverized Coal Mass Flow Rate from Feed Tanks

莊庭華(Ting-Hua Chuang)

指導教授 ： 錢建嵩

中原大學/工學院/化學工程研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300574

摘要

近年來氣相輸送已廣泛運用於粉粒體之輸送過程，因其具有無粉塵污染及適用於各種輸送管路中，因此商業化的程序操作已逐漸增加，例如發電廠及鋼鐵製程上。但在輸送過程中常發生多種問題包括管路中輸送不暢、進料槽中產生架橋現象或漏斗流動，而導致分配不均或是輸送速率不穩定，進而影響操作之穩定。
本研究針對於壓力貯槽內粉煤排放過程進行研究，實驗參數為床重、貯倉壓力及孔口大小。對加壓下粒子排放速率、貯槽內流動形態的變化及是否會生成架橋現象等進行探討，並藉由電腦模擬及攝影方法加以佐證。實驗結果顯示：粉煤排放速率較快時，易生成漏斗流動(funnel flow)，進而造成流動速率不穩定；排放速率較慢時維持穩定排放，不易生成漏斗流動，而傾向整體流動(mass flow)。

關鍵字

漏斗流動 ； 排放速率 ； 粉粒體 ； 整體流動

並列摘要

In recent years, the pneumatic conveying of powdery particles is widely used because of merits like almost no dust pollution and wide flexibility of pipeline layout. The increasing number of commercial processing operations used in such industries as electric power generation, steel production. But pneumatic conveying system has a variety of problem include unstably flow in pipes and arch phenomena or funnel flow in the feed tank. There phenomena can happen which lead to maldistribution and unstably flow rate of coal in the pneumatic system.
This work describes an experimental study of the process during pulverized coal discharge from pressurized feed tanks. The operating parameters which are studied during this work are bed weight, the pressure of feed tanks and the size of orifices. Mass flow rate, flow patterns and arching phenomena have discussed. In addition to experimental studies, the computer simulation and photographic observation have been proceeded. The results of experiment show that the faster mass flow rate causes the easier funnel flow occurring and make the mass flow rate more unstable. In the other hand, the slower mass flow rate causes the more difficultly funnel flow occurring and keeps the flow rate more stable. The flow pattern inclines to mass flow.

並列關鍵字

mass flow rate ； funnel flow ； mass flow ； powdery particles

參考文獻

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