Q.1
Largest constituent of coke oven gas is
Q.2
'Fat coals' are those coals which have very high
Q.3
Combustion of pulverised coal compared to the lumpy coal
Q.4
Use of pulverised coal in boiler furnace provides
Q.5
A travelling grate stoker is meant for the efficient burning of __________ coal.
Q.6
A coal having higher volatile matter content will necessarily have lower
Q.7
Gross & net calorific value is the same for
Q.8
Which of the following constituents of a fuel does not contribute to its calorific value on combustion?
Q.9
Higher percentage of ash in coal meant for the production of metallurgical grade coke
Q.10
Flue gas from the heating chamber of byproduct coke ovens is removed by
Q.11
A carbonaceous fuel (containing no H₂ or hydrocarbons) is burnt and the resulting flue gas contains 21% CO₂. It means that
Q.12
Which of the following is the maximum coal producing state in India?
Q.13
The temperature at which plastic layer formation takes place during carbonisation of coal varies from __________ °C.
Q.14
A coal containing very high percentage of durain is called __________ coal.
Q.15
In case of pulverised coal fired steam boiler, the secondary air serves the main purpose of
Q.16
Dust content in raw blast furnace gas is about __________ gm/Nm³ , hence it is cleaned to the dust level of about < 10 mg /Nm³ before use.
Q.17
Ignition temperature of a fuel in air is __________ that in pure oxygen.
Q.18
The average molecular weight of a flue gas having the composition by volume as CO₂ = 25%, O₂ = 25%, N₂ = 50% will be
Q.19
The gasification reaction represented by, C + H₂O = CO + H₂, is
Q.20
The lowest temperature, at which a solid fuel produces enough vapors to support continuous combustion, is called
Q.21
Which of the following fuels has the highest calorific value per unit mass (kcal/kg)?
Q.22
Tar is a better fuel than furnace oil, because of its
Q.23
Grindability index of a coal is 100. It implies that the
Q.24
Heat penetration rate in narrow coke ovens in high temperature carbonisation of coal is around __________ cm/hr.
Q.25
The reaction, C + CO₂ ⟷ 2CO, taking place during coal gasification is called the __________ reaction. n.
Q.26
Coke oven gas is a better fuel than blast furnace gas, because of its higher
Q.27
The main advantage of forced draft over natural draft is that
Q.28
A particular coal is said to be free burning when it
Q.29
High sulphur (4-6%) coal in India are found in
Q.30
Which of the following is not used as a binder in coal briquetting?
Q.31
Gross heating value of coal is __________ the net heating value.
Q.32
Yield of coke oven gas in low temperature carbonisation of coal is about __________ Nm³ /ton of dry coal.
Q.33
Artificial draught produced by a fan can be controlled by the
Q.34
A good metallurgical coke
Q.35
Atomising steam to fuel oil ratio in a burner should be around
Q.36
__________ is used as jet engine fuel.
Q.37
Gas yield in the Kopper-Totzek coal gasifier is about __________ Nm³/ton coal (ash = 35%).
Q.38
When incomplete combustion loss is high, the flue gas analysis shows large amount of
Q.39
Main constituents of benzol are
Q.40
A coal with high ash content
Q.41
Which of the following can be made into briquettes without the use of a binder?
Q.42
Octane number of 2, 2, 4 - trimethyl pen-tane is
Q.43
Yield of blast furnace gas is about __________ Nm³ /ton of pig iron.
Q.44
Degree of carbonisation of coal during coke making can be roughly judged by the __________ of the coke produced.
Q.45
Which will have the least volatile matter and hence will be the most difficult to ignite?
Q.46
Ratio of primary air to secondary air increases with increase in the rank of coal, because the
Q.47
Fuel for a nuclear reactor (thermal) is
Q.48
Pick out the wrong statement.
Q.49
Coal containing large quantity of __________ are difficult to wash.
Q.50
Gobar gas is produced by the __________ of 'gobar' (cow dung).
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