Practice Test: Question Set - 03
1. Temperature of a furnace fired with low calorific value fuel gas (i.e. lean gas) can be increased by
- (A) Preheating the combustion air
- (B) Oxygen enrichment of combustion air
- (C) Preheating the fuel gas
- (D) All (a), (b) & (c)
2. Which of the following is a periodic furnace?
- (A) Tunnel kiln
- (B) Rotary kiln
- (C) Soaking pit
- (D) Reheating furnace
3. If fuel and air are mixed ahead of the burner, it is called a/an __________ burner.
- (A) Premix
- (B) Outside mixing type
- (C) Rotary
- (D) Diffusion
4. Pulverised fuel fired furnaces employ __________ fuel firing.
- (A) Horizontal
- (B) Vertical
- (C) Tangential
- (D) All (a), (b) and (c)
5. Heat balance of furnace provides means of determining the
- (A) Thermal efficiency of the process
- (B) Sources of heat losses
- (C) Scope of reduction of heat losses
- (D) All (a), (b) and (c)
6. Main gas valve in a gaseous fuel burner is a __________ valve.
- (A) Gate
- (B) Butterfly
- (C) Globe
- (D) None of these
7. Means for giving direction to the circulation of gases in furnaces are
- (A) Fans
- (B) Arrangement of heating stock in the furnaces
- (C) Location of outlet ports and heating &
combustion devices
- (D) All (a), (b) and (c)
8. Turn down ratio of a burner
- (A) Should be as low as possible i.e., 1 : 2
- (B) Should be 1:1 for a batch type furnace
- (C) Is the ratio of maximum to minimum permissible heat input rates
- (D) Is normally much more for a continuous furnace
as compared to a batch furnace
9. Oxygen percentage in the flue gas coming out of a gaseous fuel fired furnace should be ideally about __________ percent.
- (A) < 2
- (B) < 5
- (C) < 8
- (D) < 10
10. Which is not a hearth furnace?
- (A) Glass tank furnace
- (B) Open hearth furnace
- (C) Cupola
- (D) Reheating furnace
11. Which of the following accentuates clinkering troubles on furnace grate burning coal?
- (A) Low reactivity of carbonised residue containing
high proportion of iron & sulphur
- (B) Low forced draft & fuel bed temperature
- (C) Thick firebed and preheated primary air
- (D) All (a), (b) and (c)
12. Combustion of fuel in a furnace with oxygen enriched air results in higher
- (A) Flue gas volume
- (B) Flame temperature
- (C) Fuel consumption
- (D) Stack loss
13. Cement Kiln is a
- (A) Rotary Kiln
- (B) Tunnel Kiln
- (C) Natural draft furnace
- (D) Batch furnace
14. Regenerators compared to the recuperators for the same duty
- (A) Occupy more space
- (B) Are less costly
- (C) Are of smaller size
- (D) All (a), (b) and (c)
15. Which furnace employs an I.D. fan for the removal of flue gases from the furnace?
- (A) Coke oven
- (B) Blast furnace stoves
- (C) Beehive coke oven
- (D) High pressure boiler
Next Tests: