206. Pressure drop due to pipe fittings can be estimated by the equation, , where, Le = equivalent length of straight pipeline which will incur the same frictional loss as the fitting and D = diameter of the fitting. The value of (dimensionless) for 45° elbow and 180° close return bends would be respectively around

5 and 10
45 and 75
180 and 300
300 and 500
✅ The correct answer is option B.

207. Pick out the wrong statement. In an agitated vertical cylinderical reaction vessel, the

ratio of liquid depth to tank diameter (i.e. the filling ratio) recommended for most purposes is 1.
filling ratio for dispersing gas in a liquid is 2 for sufficiently long contact period.
flat bottom and conical bottom vessels have low agitation efficiency for agitation of heavy solids in liquids.
dished bottom vessel has very high power consumption.
✅ The correct answer is option D.

210. Which of the following factors affect the pressure drop in a co-current gas-liquid absorption packed tower ?

Size, shape, orientation and surface of the packing particles.
Density and viscosity of fluids.
Fluid flow rates.
All (a), (b) and (c).
✅ The correct answer is option D.