101. Thermal efficiency of a limestone calcination rotary kiln may be around __________ percent. September 7, 2025 by Admin 20 40 65 80 ✅ The correct answer is option B.
102. The electric furnace in which heat is produced by a combination of induced current and skin effect is called __________ furnace. September 7, 2025 by Admin Arc Resistance Low frequency induction High frequency induction ✅ The correct answer is option D.
103. Which of the following is a rotary furnace? September 7, 2025 by Admin Lime kiln Soaking pit Stoves Annealing furnace ✅ The correct answer is option A.
104. Overfire burning in a furnace is a phenomenon characterised by September 7, 2025 by Admin Supply of excess fuel Supply of excess air Burning carbon monoxide and other incombustible in upper zone of furnace by supplying more air None of these ✅ The correct answer is option C.
105. Combustion of fuel in a furnace with oxygen enriched air results in higher September 7, 2025 by Admin Flue gas volume Flame temperature Fuel consumption Stack loss ✅ The correct answer is option B.
106. Oxygen percentage in the flue gas coming out of a gaseous fuel fired furnace should be ideally about __________ percent. September 7, 2025 by Admin < 2 < 5 < 8 < 10 ✅ The correct answer is option A.
107. In salt bath furnace, heat is transferred to the charge mainly by September 7, 2025 by Admin Conduction Convection Radiation None of these ✅ The correct answer is option A.
108. Fuel economy in an industrial furnace operation can not be achieved by the use of September 7, 2025 by Admin Stoichiometric combustion air Non-preheated combustion air Combustion air not enriched with oxygen Recupterators ✅ The correct answer is option A.
109. An electric furnace producing heat by means of an electric arc struck between each of three electrodes and the charge is called __________ furnace. September 7, 2025 by Admin Resistance Arc Low frequency induction None of these ✅ The correct answer is option B.
110. Which is the most thermally efficient furnace? September 7, 2025 by Admin Reheating furnace Reverberatory furnace Rotary kilns Boiler furnace ✅ The correct answer is option D.