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10.6-6. Absorption of Ammonia in Packed Tower. A gas stream contains 4.0 mol % NH, and its ammonia content is reduced to 0.5 mol % in a packed absorption tower at 293 K and 1.013 x 109 Pa. The inlet pure water flow is 68.0 kg mol/h and the total inlet gas flow is 57.8 kg mol/h. The tower diameter is 0.747 m. The film mass-transfer coefficients are k,a=0.0739 kg mol/s.m.mol frac and ka=0.169 kg mol/s.m.mol frac. Using the design methods for dilute gas mixtures, do as follows. (a) Calculate the tower height using k, a. (b) Calculate the tower height using Ka. Ans.(a) z = 2.362 m (7.75 ft)