利用氯化鋰吸收制冷之真空薄膜蒸
餾應用

蒸汽式吸收製冷系統是一種對於環境比較友善而且耗能較低的一種設備。然而，蒸汽式吸收製冷系統通常需要較大的體積及較高的熱能來驅動。為了克服以上這些問題，本篇論文採用真空式Polyvinylidenefluoride(PVDF)薄膜蒸餾系統來取代傳統的蒸汽式製冷，所選用的吸收劑為氯化鋰。並利用回應曲面法(Response Surface Methodology, RSM)來探討各個參數，如溫度、進料起始濃度及進料流速等之間的相互影響，及最式化條件。從實驗結果可發現，溫度是影響過濾端出口流速最主要的因素。經由回應曲面法所求得的最式化操作條件為 : 進料起始濃度36%、溫度在70 0C且進料流速為1.5L/min。在本篇論文中，對於熱傳導分析也進行了研究與探討。從結果可發現，其與回應曲面法所求的之結果相吻合，與其他兩個因素相比較下，溫度都會是影響最後過濾端出口流速的最主要因素。經由回應曲面法所求得的關係方程式如下 : Y = 112.3175 – 15.82156X1 + 52.3505 X2– 0.8366 X3+8.7418X1X2 +1.8537X1X3 – 4.4995X2X3– 1.3699X1X1 + 6.7305X2X2 – 4.3651X3X3，其回歸值可高達0.99，表示此一方程式可以有效的預測此系統下各個參數變化之影響。

關鍵字

蒸汽式吸收製冷系統；回應曲面法；真空式薄膜蒸餾系統

並列摘要

Vapor absorption refrigeration system (VARS) possesses environmental benefit and cheaper energy requirements. However, regenerator in VARS is often too bulky to fit in small area and need high thermal energy to operate. Membrane usage in regenerator of VARS could encounter this problem. Coupling a vacuum membrane distillation (VMD) in VARS is one of the ways since VMD only permeating water vapor. In this study, Response Surface Methodology (RSM) applied to investigate the optimal parameter (temperature, initial concentration, feed flow rate) in VMD process with permeate flux as the response. From the experiment, the analysis found that the temperature is the most significant factor with positive effect followed by concentration, which has negative effect. Obtained equation from RSM is Y = 112.3175 – 15.82156X1 + 52.3505 X2– 0.8366 X3+8.7418X1X2 +1.8537X1X3 – 4.4995X2X3– 1.3699X1X1 + 6.7305X2X2 – 4.3651X3X3 with regression value of 0.99. Suggested saddle point condition is at concentration of outside the experiment. However, form the experiment, the best response given by set of parameter of concentration at 36%, feed temperature at 70 0C and feed flow 1.5 L/min.. Heat transport analysis also performed for the experiment, and RSM applied to the result of the calculation. From the RSM calculation result showed that the experiment data used is reliable. This analysis more confirmed that the temperature is the most significant parameters in the process, followed by the concentration. Regarding considerable effect of temperature, it has strong correlation between factors and has positive effect.

並列關鍵字

optimization ； vapor absorption refrigeration system ； response surface methodology ； vacuum membrane distillation

參考文獻

[2] O. Kaynakli and R. Yamankaradeniz, “Thermodynamic analysis of absorption refrigeration system based on entropy generation,” Current Science, vol. 92, no. 4, pp. 472 – 479, 2007.

[3] Z. Wang, Z. Gu, S. Feng, and Y. Li, “Application of vacuum membrane distillation to lithium bromide absorption refrigeration system,” International Journal of Refrigeration, vol. 32, no. 7, pp. 1587–1596, Nov. 2009.

[4] IIT Kharagpur, “Lesson 14 Vapour Absorption Refrigeration Systems.” pp. 1–20.

[7] P. W. Garland, R. C. DeVault, and A. Zaltash, “Large commercial absorption chiller development program,” Washington DC, 1998.

[10] A. Elsafty and A. J. Al-Daini, “Economical comparison between a solar-powered vapour absorption air-conditioning system and a vapour compression system in the Middle East,” Renewable Energy, vol. 25, no. 4, pp. 569–583, Apr. 2002.

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利用氯化鋰吸收制冷之真空薄膜蒸餾應用

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