This set of Power Plant Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Coal Firing Systems – I”.
1. __________ of the coal is the basis for Seylor’s coal classification.
a) Proximate analysis
b) Calorific value
c) Ultimate analysis
d) Caking index
Explanation: Ultimate Analysis of the coal is the basis for Seylor’s coal classification.
2. Yield of pitch from distillation of high temperature tar is around __________ percent.
Explanation: Yield of pitch from distillation of high temperature tar is around 65 percent.
3. Caking index of the coal blend used for the manufacture of metallurgical coke should be around
Explanation: Caking index is the ability of coal to be formed into cakes. Caking index of the coal blend used for the manufacture of metallurgical coke should be around 21.
4. High excess air in combustion of fuels results in
a) smoky flame
b) increased fuel consumption
c) incomplete combustion
d) none of the mentioned
Explanation: High excess air in combustion of fuels results in increased fuel consumption. More the quantity of air in the fuel, more lean a mixture becomes.
5. The heat of combustion of a fuel
a) is equal to the heat of formation
b) is always negative
c) can’t be known without calculating it
d) is always positive
Explanation: The heat of combustion of a fuel is always negative as always some heat has to be given (supplied) to the fuel for burning it.
6. _________ has the widest inflammability limit (explosion limit) of all the gases.
a) Carbon monoxide
Explanation: Acetylene has the widest inflammability limit (explosion limit) of all the gases. That is another factor due to which the gas is used in Gas welding.
7. Main constituents of benzol are
a) benzene, toluene & xylene
b) tar & creosote
c) ammonia & phenol
d) anthracene & phenol
Explanation: Benzol comprises of benzene, toluene and xylene.
8. With increase in moisture content of coal, its
a) calorific value increases sometimes
b) bulk density always decreases
c) clinkering tendency during combustion increases
d) none of the mentioned
Explanation: None of the mentioned factors behave in the manner when the moisture content increases.
9. Oxygen percentage (by weight) in atmospheric air is
Explanation: 21 % of the atmospheric air is Oxygen.
10. In flue gas analysis by Orsat’s apparatus, carbon dioxide is absorbed by
a) cuporus chloride
b) dilute potassium carbonate
c) potassium hydroxide
d) alkaline pyragllol solution
Explanation: In flue gas analysis by Orsat’s apparatus, carbon dioxide is absorbed by potassium hydroxide.
Sanfoundry Global Education & Learning Series – Power Plant Engineering.
To practice all areas of Power Plant Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.