HW 5 - p 6.30 - Scrubbing an NH3-Air Mixture with Water in a Packed Tower- 8 pts

A 2 mol% NH3-in-air mixture at 68oF and 1 atm is to be scrubbed with water in a tower packed with 1.5 in. ceramic Berl saddles. The inlet water mass velocity will be 2400 lb/h-ft2, and the inlet gas mass velocity 240 lb/h-ft2. Assume that the tower temperature remains constant at 68oF, at which the gas solubility relationship follows Henry’s law, p = Hx. HNH3 is 2.7 atm/mol fraction.
(a) Calculate the required packed height for absorption of 90% of the NH3.
(b) Calculate the minimum water mass velocity in lb/h-ft2 for absorbing 98% of the NH3.
(c) What changes are caused by using Hiflow rings in KGa, pressure drop, maximum liquid rate, KLa, column height, column diameter, HOG and NOG?