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In a boiler, some part of heat is lost to flue ga..
1.
In a boiler, some part of heat is lost to flue gases.
A.
True
B.
False
Answer» B. False
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Related MCQs
In a boiler, some part of heat is lost to flue gases.
Boiler efficiency doesn’t depend on _____
Determine the enthalpy of 1 kg of steam if the boiler efficiency is 79%, the evaporative capacity of the boiler is 9 kg of steam per kg of fuel fired, the feed water temperature is 40°C and the calorific value of coal is 30000 kJ/kg.
Determine the evaporative capacity of a boiler in kg of steam per kg of fuel fired if the feed water temperature is 40°C, the efficiency of the boiler is 95%, calorific value of the coal fried is 33000 kJ/kg and the steam generated is dry and saturated at 12 bar pressure.
A boiler is fired with fuel having calorific value 30000 kJ/kg. It produces steam at 5 bar. The dryness fraction of the steam generated 0.85. The efficiency of the boiler is 77% and the evaporative e capacity of the boiler is 10 kg of steam per kg of fuel. Determine the temperature of feed water.
A boiler having evaporative capacity 8 kg of steam per kg of fuel produces dry and saturated steam at 13 bar pressure. The feed water temperature is 35°C. Determine the calorific value of coal if the efficiency of the boiler is 70%.
A boiler produces steam at the rate of 1500 kg per hour at 12.5 bar. The water fed to the economizer is at a temperature of 35°C and it is raised to a temperature of 110°C before feeding it to the boiler. Coal is fired at a rate of 200 kg per hour. The dryness fraction of the steam generated is 0.87. If 15% of the coal remains unburnt and the calorific value of the coal being fired is 36200 kJ/kg, determine the overall efficiency.
A boiler generates superheated steam having temperature 270°C and pressure 13 bar. The specific heat of the superheated steam 2.1 kJ/kg-K. The temperature of the feed water is 32°C. The evaporative capacity of the boiler is 8 kg of steam per kg of fuel. The calorific value of the coal is 26000 kJ/kg.
A boiler produces 4000 kg of dry and saturated steam in 6 hours. In the same time the mass of coal consumed is 300 kg of coal. The mean pressure of steam generated is 11 bar. The temperature of the feed water is 35°C. Determine the boiler efficiency if the calorific value of the fuel is 30000 kJ/kg.
Following observations were made after the trial of a boiler for 24 hours.Mass of coal burnt = 1300 kgMass of steam generated = 14000 kgMean effective pressure of steam = 10 barTemperature of the feed water = 40°CCalorific value of coal = 30000 kJ/kgCalculate the boiler efficiency if the dryness fraction of the steam generated is 0.95.
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