Free Chemical Process Principles MCQs with Answers

• A. Moisture
• B. Carbon
• C. Volatiles
• D. Ash

Explanation: Fixed carbon is the principal combustible and coke-forming constituent of coal.

• A. None of these
• B. Endothermic
• C. Autocatalytic
• D. Exothermic

Explanation: Formation of carbon dioxide from carbon and oxygen releases a large amount of heat because the products are at a lower enthalpy than the…

• A. None of these
• B. Finding out combustion efficiency
• C. Direct determination of nitrogen in flue gas by absorbing it in ammoniacal cuprous chloride
• D. Gravimetric analysis of flue gas

Explanation: An Orsat apparatus performs volumetric analysis of flue gas by selectively absorbing carbon dioxide, oxygen and carbon monoxide, with…

• A. 60
• B. 160
• C. 500
• D. 750

Explanation: Low-temperature carbonisation produces substantially less gas than high-temperature coke-oven carbonisation, with a typical yield near 160…

• A. CO2
• B. CH4
• C. CO
• D. S

Explanation: Carbon monoxide is the combustible component of blast-furnace gas and burns with a characteristic bluish flame.

• A. 8800 kcal/m3
• B. 25000 kcal/kg
• C. Same as that of coal middling
• D. 8800 kcal/kg

Explanation: The calorific value of pitch creosote mixture C.T.F.-200 is approximately 8800 kcal/kg.

• A. It reduces its calorific value tremendously
• B. The hydrocarbons crack thereby choking and fouling the heat transfer surface by carbon soot
• C. It reduces its flame temperature tremendously
• D. There are chances of explosion during preheating

Explanation: Preheating hydrocarbon-containing fuel gases can crack the hydrocarbons and deposit carbon soot, choking or fouling heat-transfer…

• A. Junkers
• B. Boy's
• C. Bomb
• D. None of these

Explanation: A bomb calorimeter measures the heat of combustion of solid and liquid fuels in a sealed oxygen vessel.

• A. 500
• B. 1500
• C. 6500
• D. 20000

Explanation: Bituminous coal commonly has a calorific value near 6500 kcal/kg, although the exact value varies with moisture, ash, and rank.

• A. Controlling the excess air
• B. Oxygen enrichment of combustion air
• C. Using low c.v. fuels
• D. Maintaining proper draft in the furnace

Explanation: Excess air carries hot combustion gases out of the stack, so controlling it reduces the sensible heat lost with those gases.

• A. Back draughting
• B. Banking
• C. Under pressurising
• D. None of these

Explanation: Banking means maintaining a furnace fire during a standby period by restricting air and covering or arranging the fuel so it burns slowly.

• A. Contains more volatile matter than bituminous coal
• B. Ignites more easily than bituminous coal
• C. Burns with short, bluish, yellow-tipped flame producing very little smoke
• D. Is essentially a coking coal

Explanation: Anthracite has very low volatile matter, ignites less readily than bituminous coal, and burns with a short bluish flame producing little…

• A. Fully
• B. Partially
• C. Negligibly
• D. Not at all

Explanation: Beehive ovens are non-recovery coke ovens, so the volatile by-products are burned within the oven rather than collected.

• A. Splint
• B. Bright
• C. Non-banded
• D. Boghead

Explanation: Splint coal is rich in durain and is dull, hard, and commonly non-caking.

• A. Pneumatically convey the pulverised coal
• B. Completely burn the volatile matter
• C. Burn the lumpy coal
• D. None of these

Explanation: Primary air supports ignition and partial combustion, while secondary air is admitted above the fuel bed to supply oxygen for burning the…

• A. 30
• B. 65
• C. 120
• D. 180

Explanation: Coke-oven gas is cooled to roughly 65°C before entering the saturator, where ammonia is absorbed in water or acid liquor for recovery.

• A. Partial combustion of coal
• B. Atmospheric pressure gasification of coal (e.g., in Kopper-Totzek gasifier)
• C. High pressure gasification of coal (e.g. in Lurgi gasifier)
• D. Partial combustion of large size (< 50 mm) coke

Explanation: Gasifying large coke produces very little tar because coke contains little volatile matter, the main source of tar.

• A. Dew point
• B. CO content
• C. CO2 content
• D. O2 content

Explanation: Incomplete combustion leaves unoxidized carbon in the form of carbon monoxide, so a high CO concentration in the flue gas indicates poor…

• A. Benzol
• B. Pyridine
• C. Toluene
• D. Cerosote

Explanation: TNT is trinitrotoluene, made by nitrating toluene in successive stages.

• A. Height of the coal heap should be < 3 metres
• B. Maximum 200 tons should be stored in a heap
• C. Neither A. nor B.
• D. Both A. and B.

Explanation: High-volatile bituminous coal can self-heat because oxidation is promoted in large, poorly ventilated heaps.