Process Equipment and Plant Design
Steam economy is defined as the amount of evaporation per unit amount of steam used, while the capacity is the total evaporation obtained per hour. Use of multiple effect in evaporation
In operations involving large temperature changes. (e.g. distillation), plate towers are preferred over packed towers as the packing may be crushed due to large temperature changes
The total weight of a dry plate tower is usually much more than that of a dry packed tower designed for the same duty
Plate tower is perferred, if interstage cooling is required to remove heats of reaction or solution
Plate tower is preferred over packed tower, if the operation involves liquids containing dispersed solids
Minimum cleaning lane of 6.5 mm is provided, when tubes are on a square pitch
Minimum tube sheet thickness (in which tubes are fixed) is equal to the O.D. of the tube upto 15 mm tube diameter; and for > 15 mm tube diameter, tube sheet thickness is smaller than tube diameter
O.D. of the tube is 6 to 40 mm while the tube lengths used are 0.5, 2.5, 3.0, 4.0, 5.0, 6 metres
Providing a higher skirt clearance or a higher weir
Decreasing the number of rows of caps through which the liquid flows or by decreasing the velocity of liquid flow past the caps or by reducing the distance along the tray through which the liquid must
Using split flow, radial flow or cascade flow for column diameter large than 4 ft
EXAMIANS