Effective area of a highly efficient random packing

The effective area of a metal Raschig Super-Ring with a nominal diameter of 20–70 mm has been investigated. The liquid superficial velocity varies between 5 and 200 m3/(m2 h) but not higher than the one at the loading point. The initial gas velocity was kept constant, equal to 4000 kg/(m2 h). The absorption of CO2 in 1N NaOH solution was used as a model system. The column diameter was 470 mm and the packing height—2400 mm. The liquid phase distributor ensured 923 drip points per m2. The values of the mass transfer coefficient (KGa) under these conditions are also represented. The results show that at high liquid superficial velocity the effective area of the investigated packings is higher than their specific area. For example, the packing with nominal diameter 70 mm has an effective area more than twice higher than its specific area. That means that under these conditions the surface of the drops and jets, trickling into the free volume of the packing is more than its specific area. An equation for calculating the effective area has been obtained. Its average error amounts to 4.5%. The maximum deviation does not exceed 10%.