批次結晶程序整體設計之發展

Development of recipes for seeded batch crystallization

曾郁迪(Yu-Ti Tseng)

指導教授 ： 吳哲夫

國立臺灣大學/工學院/化學工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.03318

摘要

在此研究中我們對於批次結晶程序做了整體性的分析及探討。首先我們探討了給予長晶速率限制條件對程序的影響。對於特定操作條件我們發現增加限制條件對於產品品質沒有顯著影響。接著我們探討晶種負載率的影響。我們發現提高晶種負載率能更有效率壓制成核以及成核速率。另外此研究中我們透過電腦模擬針對兩個結晶系統以及無因次系統做了晶種分析圖。對於臨界晶種負載率我們導出無因次的關係式，研究發現此關係式對於預測模擬結果有很高的準確度。我們探討了臨界晶種總表面積以及臨界晶種總長度，然而這兩個變數不建議做為設計變數。此研究中我們也探討了總反應時間以及淨結晶產量對於批次結晶程序的影響，結果可用做設計結晶程序的簡單方針。

關鍵字

長晶速率限制 ； 臨界晶種負載率 ； 總反應時間 ； 淨結晶產量

並列摘要

In this work we investigate the development of recipes for seeded batch crystallization processes. First we investigate the effect of growth rate constraint. For a particular case we find that such a constraint does not have a significant influence on product quality. Then we investigate the effect of seed loading. We find that the seed mass has a large influence on decreasing the final nuclei mass and efficiently suppressed the nucleation rate. In this work seed charts for two dimensional systems and the dimensionless system are produced and used to determine critical seed loading ratio by computer simulation. An analytical expression for the critical seed loading is derived and simulation results show high accuracy for predicting critical seed loading ratio versus dimensionless seed mean size using constant growth rate trajectory. We investigate two critical values which are critical seed surface area and critical seed total length. However these two critical values are not recommended to use as the design variables. In this work we also investigate the effect of total batch time and the net crystal yield on the batch process, and the results can be used as the design guideline.

並列關鍵字

growth rate constraint ； critical seed loading ratio ； total batch time ； the net crystal yield

參考文獻

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2. Jagadesh D, Chivate MR, Tavare NS. Batch Crystallization of Potassium-Chloride by an Ammoniation Process. Industrial & Engineering Chemistry Research 1992;31(2): 561-68.

3. Kubota N, Doki N, Yokota M, Sato A. Seeding policy in batch cooling crystallization. Powder Technology 2001;121(1): 31-38.

4. Doki N, Kubota N, Sato A, Yokota M, Hamada O, Masumi F. Scaleup experiments on seeded batch cooling crystallization of potassium alum. Aiche Journal 1999;45(12): 2527-33.

5. Doki N, Kubota N, Sato A, Yokota M. Effect of cooling mode on product crystal size in seeded batch crystallization of potassium alum. Chemical Engineering Journal 2001;81(1-3): 313-16.