An absorber is to be designed for reducing a process offgas, initially containing 12.5% to 0.4% HCl by volume. HCl-free water at 293 K and 1.013×105 Pa pressure will be fed to the top of a packed, 0.6-m-diameter column, flowing countercurrent to the rising gas stream. Preliminary design calculations indicate that an operating Ls/Gs ratio should be 1.64 times the minimum Ls/Gs ratio. With these flow rates, the overall mass-transfer capacity coefficient, KGa, may be taken as 8.8 kg mol/m3.s: Pa. The equilibrium relation for solutions of HCl in water at 293 K is given by the following data:

Determine

a. the percentage of HCl to be removed by the absorption process;

b. the exit concentration of the acid stream;

c. If 5 m3 /min of process off-gas, measured at 293 K and 1.013×105 Pa pressure, are blown into the tower, determine the height of ceramic packing required in the absorber.