441. Use of preheated air for combustion of fuel in the furnace, increases the September 7, 2025 by Admin Scale losses of the furnace stock Calorific value of the fuel Flame temperature None of these ✅ The correct answer is option C.
442. Low temperature oxidation of coal is accelerated by the September 7, 2025 by Admin Storage in large heaps Storage in compressed piles Absence of porous or friable particles All of the above ✅ The correct answer is option A.
443. Calorific value of coal middling generated in coal washeries during washing of coal may be around __________ Kcal/kg. September 7, 2025 by Admin 1000 4000 6000 8000 ✅ The correct answer is option B.
444. Micum Index of a coke is a measure of its September 7, 2025 by Admin Reactivity Porosity Bulk density Hardness & strength ✅ The correct answer is option D.
445. Ash content in the coke produced from a coking coal having 20% ash may be around __________ percent. September 7, 2025 by Admin 6 12 18 24 ✅ The correct answer is option D.
446. Too much of excess air in combustion results in high September 7, 2025 by Admin Fuel consumption for the same heat load Stack gas temperature Percentage of oxygen in flue gases All of the above ✅ The correct answer is option D.
447. Which of the following would require maximum amount of % excess air for complete combustion? September 7, 2025 by Admin Coke oven gas Furnace oil Pulverised coal Lump coal (fixed on chain grate) ✅ The correct answer is option D.
448. The cuprous chloride used in orsat apparatus can absorb September 7, 2025 by Admin Only CO Both CO and CO₂ Both CO and O₂ All of the above ✅ The correct answer is option D.
449. Calorific value of bituminous coal may be around __________ Kcal/kg. September 7, 2025 by Admin 500 1500 6500 20000 ✅ The correct answer is option C.
450. Calorific value of gobar gas (containing CH₄ = 60% , H₂ = 10% ; CO₂ = 30%) may be about __________ Kcal/Nm³. September 7, 2025 by Admin 1800 3200 5400 10200 ✅ The correct answer is option C.