Ammonium sulfate ((nh4)2so) is dried from 4.0% to 0.2% moisture in a countercurrent rotary drier. hot air at 363 k and containing 0.01 kg/kg dry air is admitted at one end of the drier feed, flows countercurrently in contact with the solids, and leaves at the other end of the drier at 305 k. the solid enters at 298 k and leaves at 333 k. the heat loss from the drier is estimated to be 4 x 104 kj/hr. estimate the air requirement for the drier (in kg/hr) for producing ammonium sulfate at the rate of 1000 kg/hr. data: latent heat of vaporization of water at 273 k = 2502.3 kj/kg! heat capacity of dry air = 1.005 kj/kg. k heat capacity of water vapor = 1.884 kj/kg. k heat capacity of water = 4.2 kj/kg. k heat capacity of dry (nh4)2so4 = 1.507 kj/kg. k