7HF - Process Equipment Design - October 1998
Part A (20 x 2 = 40 Marks)
- As the operating temperature increases the design stress decreases
- When radio graphic tests are conducted for pressure vessels, the joint efficiency is 0.85 for spot radiography and 1.00 for 100% radiography.
- For stainless steel materials the corrosion allowance is zero.
- For elliptical heads the ratio of major axis to minor axis is 2:1
- What losses are taking place in the storage of volatile liquids? Evaporation losses, filling losses, breathing losses.
- What is TEMA? Tubular Exchangers Manufacturers Association, USA. Heat Exchanger design and fabrication Code.
- Corrosive fluids are passed through tube side of a shell and tube heat exchanger
- Baffles are provided in agitated vessels to prevent swirling.
- For triple effect evaporators the economy is approximately three.
- Heat transfer coefficient has the units of W/(m2.K) in SI.
- Plate thickness: hole diameter is between ______:______ for sieve trays
- At minimum reflux ratio infinite number of plates are required for distillation.
- Define loading
- A redistributor is used for every 3D (i.e., 3 times the diameter of height) of the packed section.
- In a dryer, number of flights ranges from _____D to _____D where D is in feet.
- Define cut size for a cyclone separator. (The minimum diameter of particle that can be collected with 100% efficiency)
- Formation of new crystals is termed as __________.
- What is an induced draft cooling tower? (Air is sucked by the fans at the top of the tower)
- Indicate any two advantages of pressure filter
- Define critical speed of centrifuge
Part B (5 x 12 = 60 Marks)
- (a) 10,000 kg/hr of a hot fluid is to be cooled from 90oC to 45oC using a cold fluid available at 30oC. The cold fluid leaves the exchanger at 42oC. Both fluids have the properties similar to that of water. Design a suitable shell and tube heat exchanger. The overall heat transfer coefficient is 450 W/m2.K. 2.54 cm dia and 4 m long tubes are used.
(b) Draw the sketch of a reboiler and indicate the parts.
- (a) A continuous distillation column is used to separate a feed mixture containing 25 mole percent Benzene and remaining toluene into a distillate containing 95% benzene and the bottom product containing 90% toluene. Feed is at its bubble point. A reflux ratio of twice the minimum is used. The overall efficiency is 60%. Design a suitable distillation column after choosing reasonable gas mass velocity. aAB = 2.5
(b) Draw the sketch of a packed column. Indicate parts such as distributor for liquid, redistributor, packing support, packing materials etc.
- (a) Give a stepwise procedure for the design of a rotary dryer
(b) Draw neat sketch of crystallizer of your choice
- (a) Draw the sketch of a reaction vessel. Indicate the parts such as agitators, flanged enclosures, cooling coil etc.
(b) Draw the sketch of different types of dished heads
- (a) Draw the sketch of a rotary drum filter and indicate the parts
(b) Draw the sketch of a storage tank for non-volatile liquid