Chemical Heat Transfer

A. Through a metallic wall
B. By direct contact of hot flue gas with air
C. By heating an intermediate material (like chequor bricks) and then heating the air from this
hot material
D. None of these

A. 6000
B. 24000
C. 60000
D. 48000

A. 1.66
B. 88.66
C. 3.66
D. Dependent on NRe only

A. Corrosiveness
B. Fouling characteristic
C. Viscosity
D. None of these

A. 1
B. 0
C. 0.78
D. 0.95

A. Boiling point elevations
B. Temperature of the feed
C. Rate of heat transfer
D. Ratio of the weight of the thin liquor to thick liquor

A. Exit-fluid temperature > wall temperature
B. Exit fluid temperature < wall temperature
C. Exit fluid temperature = wall temperature
D. Graetz number > 100

A. High vacuum in the evaporator
B. High evaporation rate
C. Foaming of the solution
D. High heat transfer rate

A. Provide very large heat transfer co-efficient
B. Results in making part of the heating surface inactive
C. Results in abruptly increased velocity
D. None of these

A. LMTD is greater
B. Less surface area is required for a given heat transfer rate
C. Both A. and B.
D. More surface area is required for a given heat transfer rate