Experimental analysis on chemical dehumidification of air in a packed column by hygroscopic salt solution: Comparison between structured and random packings

This paper presents the experimental tests on chemical dehumidification of air by liquid desiccant carried out in a packed column with the hygroscopic solution H2O/LiBr. Two types of absorption columns, namely, random packing consisting of 1 in. Pall Ring elements and a structured column Mellapack 250Y, were tested. The experimental tests are presented in terms of humidity reduction, dehumidification efficiency, and air-side pressure drop. The random packing shows the dehumidification rate and efficiency as 20%–30% higher than structured packing, whereas the structured packing shows the air-side pressure drop as 65%–75% lower. The experimental results are also compared with the values predicted by one-dimensional simulation code of a packed column, and a fair agreement is found between experimental and simulated values for both dehumidification rate and air-side pressure drop. The experimental tests show that the chemical dehumidification of air by H2O/LiBr in a packed column with random and structured packings ensures a consistent reduction in the humidity ratio suitable for the application to air-conditioning and drying processes.