Question: 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_______?

• 1. Tar
• 2. Sulphide Coke
• 3. Coke Oven Gas
• 4. Pulverised coke

Question: Coal tar (produced by high temperature carbonization) is the main source of_________?

• 1. Aromatic compounds
• 2. Aliphatic compounds
• 3. Paraffins
• 4. Olefins

Question: ______________ is an indirectly heated furnace?

• 1. Open hearth furnace
• 2. Muffle furnace
• 3. Soaking pit
• 4. Reheating furnace

Question: Fuel economy in furnaces can be achieved by_________________?

• 1. Using oxygen enriched combustion air
• 2. Preheating the combustion air
• 3. Reducing the heat loss through furnace openings & doors
• 4. All A, B and C

Question: Ingress of cold air in the furnaces through cracks, charging doors, openings etc ________________?

• 1. Reduces the flue gas temperature and makes the furnace atmosphere oxidising
• 2. Increases the load on the induced draft fan
• 3. Reduces the furnace draught
• 4. All A, B & C

Question: Which is the most thermally efficient furnace _______________________?

• 1. Reheating furnace
• 2. Reverberatory furnace
• 3. Rotary kilns
• 4. Boiler furnace

Question: The advantages of firing pulverised coal in the furnace lies in the fact that, it_____________________?

• 1. Permits the use of high ash content coal
• 2. Permits the use of low fusion point ash coal
• 3. Accelerates the burning rate and economises on fuel consumption
• 4. All A, B and C

Question: _____________ furnace is not an electric furnace?

• 1. Arc
• 2. Induction
• 3. Pot
• 4. Resistance

Question: To reduce the stack loss, heat recovery from flue gas can be done by_____________________?

• 1. Preheating of cold stock
• 2. Preheating of combustion air
• 3. Steam generation in waste heat boilers
• 4. All A, B & C

Question: Size of the combustion chamber of a furnace depends upon the ___________________?

• 1. Heat release rate of the fuel
• 2. Preheat temperature of fuel & air
• 3. Method of mixing the fuel & air
• 4. All A, B and C