chemical engineering fuels and combustion MCQs – Page 19

Practise multiple-choice questions from chemical engineering fuels and combustion for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

chemical engineering fuels and combustion Mcqs
361. Which of the following is a single stage, fixed bed high pressure coal gasification process ?
comments icon0

A. None of these

B. Kopper-Totzek process

C. Lurgi Process

D. Winkler process

362. With increase in calorific value of fuels, their adiabatic flame temperatures__________________?
comments icon0

A. Increase

B. Remain unchanged

C. May increase or decrease; depends on the quantity of products of combustion

D. Decrease

363. About _____________ Nm3 of air will be required for the complete combustion of 2Nm3 of CO?
comments icon0

A. 3

B. 4

C. 2

D. 5
364. Function of secondary air in pulverised coal firing is to_________________?
comments icon0
A. Ensure efficient burning of coal around the burner

B. Transport the coal to the burner

C. Reduce primary air requirement

D. Dry the coal

365. Anthracite can be used for___________________?
comments icon0

A. Blending with highly coking coal to check its swelling which helps in saving coke even walls

B. Recarbonising steel

C. All A., B. and C.

D. m damage and to produce high strength coke

E. Making carbon electrodes

366. A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the_________________?
comments icon0
A. Lack of thorough mixing of fuel with air

B. High sulphur content in the fuel

C. Low calorific value of the fuel

D. Presence of large quantity of hydrogen in the fuel

367. A coal with high _____________ content, would ignite most easily?
comments icon0

A. Fixed carbon

B. Volatile matter

C. Oxygen

D. Ash

368. In flue gas analysis by Orsats apparatus, carbon dioxide is absorbed by______________________?
comments icon0

A. Cuprous chloride

B. Dilute potassium carbonate

C. Alkaline pyrogallol solution

D. Potassium hydroxide
369. High temperature carbonisation of coal takes place at _______________ C?
comments icon0

A. 2000

B. 600

C. 1100

D. 1600

370. Which of the following is not a by-product recovered in a high temperature coal carbonisation plant ?
comments icon0

A. Pitch-creosote mixture (PCM)

B. Benzol

C. Naphthalene

D. Ethylene
371. Critical Air Blast (CAB) value of coke is a direct measure of its__________________?
comments icon0

A. Strength

B. Hardness

C. Reactivity

D. None of these

372. Emission of dense white smoke out of the chimney of a thermal power plant is an indication of the use of__________________?
comments icon0

A. Correct amount of air for combustion

B. Less air for combustion

C. Too much air for combustion

D. Pulverised coal in boilers

373. Which of the following fuels is generally not used in thermal power plant boiler firing ?
comments icon0

A. Coal middling from washeries

B. B.F. gas, coke oven gas and L.D. converter gas

C. Furnace oil, light diesel oil and tar/PCM

D. Pulverised coking coal
374. Efficient burning of anthracite coal requires______________________?
comments icon0
A. Fine grinding

B. All A., B. and C

C. Low preheat of air

D. High excess air

375. Which of the following would require maximum amount of % excess air for complete combustion ?
comments icon0

A. Coke oven gas

B. Furnace oil

C. Lump coal (fixed on chain grate)

D. Pulverised coal

376. Which of the following is not a manufactured fuel ?
comments icon0

A. Furnace oil

B. Kerosene

C. Semi-coke

D. Bagasse
377. Out of the following fuels, the difference between gross and net calorific value will be minimum in case of___________________?
comments icon0

A. Coke oven gas

B. Natural gas

C. Blast furnace gas

D. Water gas

378. Hard pitch is used for making_____________________?
comments icon0
A. Pulverised fuel

B. Perfumes

C. Plastics

D. Insecticides

379. Which of the following constituents of a fuel does not contribute to its calorific value on combustion ?
comments icon0

A. Sulphur

B. None of these

C. Hydrogen

D. Carbon

380. For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3), while the C.V. is same on weight basis (i.e., kcal/kg) ?
comments icon0

A. Sewage gas and gobar gas

B. B.F. gas and coke oven gas

C. Propane and LPG

D. Propane and acetylene