Design of packed column for absorbtion cooling system

After a comparasion of a absorption refrigeration with mechanical vapor compression systems, it is concluded that a mechanical compression system has little thermodynamic superiority over an absorption system. On the other hand, one uses less costly low temparature heat energy which can be collected from the sun or industrial waste heat, the other uses mechanical energy which is very costly. To develope the coefficient of performance of the absorption refrigeration system attentions must be given the most appropriate refrigerant-absorbent systems and the design of absorbers. A models is proposed for an evaluation and comparasion of different refrigerant- absorbent systems. Only limited data is required for this analysis and this is mostly available in the literature. The method is used for comparasion of eleven promising systems. From these NH3 - LİNO3 has the best performance. However, because of the difficulties that encountered in the absorber the system is still thermodynamically less effective than mechanical vapor compression. In order to final a solution for the slow mass transfer rate by absorption, the simultanious processes of chemical reaction and absorption is being analyzied. The best absorbent-refrigerant system for refrigeration is found to be CO2 and MEA solutions. Enhancement factor (<|> ), which can be described as the ratio of chemical reaction mass transfer rate to physical mass transfer rate is found approximately 10 at the same process conditions. The absorption proceess has been taken into consideration for calculation of effective interphase area (a), and concentration of interphase between gas-liquid (Cm), in packed bed. In reality, with the effect of chemical reaction these values can be risen. In this study, effective interphase area (a), and concentration recalculated with the effect of chemical reaction and absorption, simultaneously, and the hight of packed column calculated accordingly.