Practice Test: Question Set - 01
1. Combustion of pulverised fuel
- (A) Requires
larger combustion chamber than rich gaseous fuel
- (B) In
a metallurgical furnace does not contaminate the product in the furnace by ash
from fuel
- (C) Suppresses
the discharge of fine dust and grit into atmosphere
- (D) All (a), (b)
and (c)
2. Caking index of a coal is a measure of its
- (A) Abradability
- (B) Reactivity
- (C) Agglutinating
(binding) properties
- (D) Porosity
3. White flue gas (resembling steam) coming out of the chimney of a thermal power plant indicates that the fuel used in the boiler furnace is
- (A) Tar
- (B) Coke oven
gas
- (C) Pitch
- (D) Pulverised
coke
4. Main component of sewage gas produced during anaerobic decomposition of organic waste (by suitable bacteria) during sewage disposal is
- (A) H2
- (B) CH4
- (C) CO2
- (D) N2
5. Spontaneous combustion of coal on storage results due to
- (A) Inadequate
ventilation
- (B) Low
temperature oxidation
- (C) Storage
in large heaps with small surface to volume ratio
- (D) All (a), (b)
and (c)
6. The shift conversion reaction taking place during water gas manufacture is given by
- (A) C + H2O ↔ CO
+ H2
- (B) C + 2H2O ↔ CO2 +
2H2
- (C) CO + H2O ↔ CO2 +
H2
- (D) None
of these
7. 'Wobbe index' is a characteristic of
- (A) Solid
fuels
- (B) Gaseous
fuels
- (C) Liquid
fuels
- (D) Fat
coals
8. __________ of the coal is the basis for Seylor's coal classification.
- (A) Proximate
analysis
- (B) Ultimate
analysis
- (C) Caking
index
- (D) Calorific
value
9. In case of pulverised coal fired steam boiler, the secondary air serves the main purpose of
- (A) Transportation
of coal
- (B) Drying of
coal
- (C) Combustion
of coal by supplying it around the burner
- (D) Preheating
the primary air
10. The optimum percentage of excess air for combustion depends upon the __________ of the fuel.
- (A) Type (solid,
liquid or gaseous)
- (B) Calorific
value
- (C) Sulphur
content
- (D) Ignition
temperature
11. In flue gas analysis by Orsat's apparatus, carbon monoxide is absorbed by
- (A) Cuprous
chloride
- (B) Potassium
hydroxide
- (C) Alkaline
pyrogallol solution
- (D) None
of these
12. Presence of free moisture in coal during its high temperature carbonisation
- (A) Reduces
the coking time
- (B) Protects the
volatile products from pyrolysis (cracking) in the presence of hot coke and hot
oven walls
- (C) Increases
the loss of fine coal dust from the ovens when charging
- (D) None
of these
13. Washing of coal decreases its
- (A) Caking
index
- (B) Mineral
matter content
- (C) Ash
content
- (D) Both (b) and
(c)
14. In high temperature carbonisation of coal compared to low temperature carbonisation
- (A) Yield
of ammonia is less
- (B) Aromatic
content of tar is low
- (C) H2 content
in the coke oven gas is more
- (D) Calorific
value of the coke oven gas is lower
15. To avoid fire by spontaneous combustion of coal due to its low temperature oxidation, it should be stored in
- (A) Shallow
and small piles
- (B) Fine
sizes without the presence of any lump
- (C) Closed
space without any ventilation facility
- (D) Large
heaps with small surface to volume ratio