蒸餾塔操作診斷系統建置

Deployment of a diagnosis system for the operation of distillation columns

林祥旻(Shyang Ming Lin)

指導教授 ： 張煖

淡江大學/工學院/化學工程與材料工程學系碩士班/碩士(2018年)

https://doi.org/10.6846/TKU.2018.00431

摘要

傳統上，雖然可以利用程序模擬與分析軟體來進行程序操作診斷與製程改善，但常出現數據處理耗費大量人力與時間、模型精準度欠佳且欠缺分析設備效能之直接數值等問題。本技術報告使用Aspen Plus之「工廠數據」及「數據調和」兩項功能建立蒸餾塔操作診斷系統，以解決前述問題，並以具有實廠數據之甲醇蒸餾塔與環己酮純化塔為探討案例。
甲醇蒸餾塔之性能診斷結果為該塔之不合理效率並非由於溫度量測誤差導致調和結果不佳所致，而是該塔操作於不適當的水力條件所造成。第二座冷凝器總括熱傳係數偏低是因熱交換量過低所致。
環己酮純化塔之性能診斷結果為該塔之不合理效率可能是溫度計誤差造成，水力分析結果則顯示該塔操作於適當的水力條件。
此診斷系統也進一步用以調和速率模式之氣液介面面積修正因子，並建立該修正因子與進料流量之二次多項式關聯式。此預測模型並成功地應用於決定環己酮純化塔的則最大處理量與操作變量(回流量、蒸汽量)。此預測模型將可應用於導引式程序模擬器(Guiding Process Simulator, GPS)。

關鍵字

蒸餾塔 ； 診斷 ； 分離效率 ； 數據調和 ； 工廠數據

並列摘要

Traditionally, the process simulation and the analysis software can be used for the diagnosis of process operation and process improvement. However, the shortfalls include the extensive human resource and time, poor model accuracy and lacking of direct numerical index for equipment performance. The purpose of this study is to solve these problems by deploying a diagnosis system for the operation of distillation columns by employing the “Plant Data” and “Data Reconciliation” functions provided in Aspen Plus. A methanol distillation column and a cyclohexanone purification column with real plant operating data were chosen for case study.
The performance diagnosis of the methanol distillation column reveals that the reason for the unreasonable low efficiency of the tower is not due to the temperature measurement errors, rather it is caused by the failure of operating within the proper hydraulic regime. The hydraulic problem is resulted from the low-feed-rate operation conditions. For the heat exchangers, because the second condenser is operated under very small heat duty, very low heat transfer coefficient is obtained.
The performance diagnosis of the cyclohexanone purification column reveals that temperature measurement errors can probably cause the unreasonable low efficiency of the tower. The hydraulic analysis shows that the column is operated in the proper regime.
The real plant data is further used to reconcile the area correction factor (ACF) in of the gas-liquid interfacial area in the rate-based model and a quadratic polynomial correlation of the area correction factor and feed flow has been developed. The reconciled rate-based model is successfully employed to determine the maximum throughput and operating variables (reflux flow and steam flow) for the cyclohexanone purification column. This prediction model can be applied to Guided Process Simulator (GPS).

並列關鍵字

distillation ； diagnosis ； efficiency ； data reconciliation ； plant data

參考文獻

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