Theoretical and Experimental Studies on the Heavy Water Enrichment in concentric-tube Frazier-scheme thermal-diffusion Columns under flow-rate Fraction and Plate Spacing Variations

串聯多根Frazier型熱擴散塔提煉重水之理論與實驗研究

何啟東(Chii-Dong Ho) ； 鄭東文(Tung-Wen Cheng) ； 陳永宗(Yun-Tsung Chen) ； 郭家展(Jia-Jan Guo)

《Journal of the Chinese Institute of Chemical Engineers》 38卷1期 (2007/01) Pp. 53-62

摘要

本文主要探討變出料分率對串聯多根Frazier型熱擴散塔提煉重水效率之研究。其中推導了在不同進出料分率與固定操作成本下之分離度公式，並在不同設計與操作條件不對多根Frazier型熱擴散塔提煉重水效率的影響，且與塔頂和塔底等進出料流率及固定板距為0.04公分之串聯多根Frazier型熱擴散塔之分離度作比較。結果顯示，相較於塔頂和塔底等進出料流率及固定板距為0.04公分之串聯多根Frazier型熱礦散塔，具塔頂和塔底不同出料分率與最佳板距的質傳效率有顯著的改善和提升。
藉由數學理論之計算和實驗數據之比較，理論預測與實驗結果是相當吻合的。結果亦證實，藉由調整適當的進出料分率與冷熱板之間的距離，可以有效降低再混合效應，使得分離度改善率相對地提高。

並列摘要

An influence of plate spacing on heavy water enrichment in continuous concentric-tube Frazier-scheme thermal-diffusion columns at fixed operational expense has been investigated, both theoretically and experimentally, under flow-rate fraction variations. The analytical predictions are represented graphically and compared with those of a classical Frazier-scheme having the same column length and flow-rate fraction at both the top and the bottom of the column. Considerable improvement in the separation efficiency of the heavy water in thermal-diffusion columns of the same working dimensions is achieved by employing a Frazier-scheme with optimal plate spacing (2w)(superscript *) and flow-rate fraction variations. Experimental work was conducted to confirm the quantitative agreement with the theoretical prediction of the separation efficiency and the proposed separation theory. The effects of the plate spacing and flow-rate fraction on the separation efficiency of heavy water enhancement in the Frazier-scheme thermal-diffusion column with the column number, feed fraction concentration and feed mass flow rate have also been discussed.

並列關鍵字

Thermal-diffusion columns ； Frazier-scheme ； Plate spacing ； Flow-rate fraction ； Water isotopes