. A spray-drying operation similar to that described in Problem 5.23 is used by the pharmaceutical industry. Acetaminophen is an active pharmaceutical ingredient (API) that can be produced in powdered form by spray drying. A mixture of the API containing 75 wt% water is fed to an atomizer in a dryer where it is brought into contact with hot air that enters the dryer at 220°C and 6.0 bar. All of the water is evaporated. The outlet gas contains 8.1 mole% water and leaves the dryer chamber at 80°C and 1.0 atm absolute with a flow rate of 513:6 m3 /h. Calculate the production rate of powdered API and the volumetric flow rate of inlet air.

Explain the difference laminar and turbulent flow. explain it with the shear stress and the velocity profiles.

What precautions should you take to prevent injuries when dealing with heavy loads?

A3-mm-thick panel of aluminum alloy (k 177 w/m-k, c 875 j/kg-k and ? = 2770 kg/m) is finished on both sides with an epoxy coating that must be cured at or above t,-150°c for at least 5 min. the production line for the curing operation involves two steps: (1) heating in a large oven with air at ts,0-175°c and a convection coefficient of h, 40 w/m2. k, and (2) cooling in a large chamber with air at 25°c and a con- vection coefficient of he 10 w/m2.k. the heating portion of the process is conducted over a time interval te which exceeds the ime required to reach 150°c by 5 min (h = r + 300 s). the coating has an emissivity of ? = 0.8, and the temperatures of the oven and chamber walls are 175 and 25°c, respectively. if the panel is placed in the oven at an initial temperature of 25°c and removed from the chamber at a safe-to-touch tempera ture of 37°c, what is the total elapsed time for the two-step curing operation?