Question

Q2. An absorption column randomly packed with 25mm ceramic Raschig rings is to be used to reduce the mole fraction of solute A from 0.04 to 0.005 at constant pressure and temperature by using pure liquid solvent. Total molar flow rates of entering gas and liquid are 90 kmol/h and 170 kmol/h, respectively. The equilibrium relationship at operating condition is given as yº = 1.5 x and the gas side pressure drop in the column is selected as 200 Pa/m. By using the additional data given below calculate a) Diameter of the column b) Percent of flooding gas velocity at operating conditions. c) Height of the column, when height of the one overall liquid transfer unit is 0.95 m. MW= 29 kg/kmol, MW= 18 kg/kmol, pa = 1.2 kg/m², PL = 998 kg/m², ui= 1 cP