Coal containing large quantity of __________ are difficult to wash.
(A) Ash
(B) Inherent mineral matter
(C) Free impurities
(D) Volatile matter

1 Answer

Answer :

(B) Inherent mineral matter

Related questions

Description : Washing of coal is done to reduce the (A) Inherent impurities (B) Adhering impurities (C) Mineral matter (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

Description : A coal containing high amount of volatile matter will have (A) Low ignition temperature (B) Very little ash content (C) High fusion point of its ash (D) Low adiabatic flame temperature

Last Answer : (A) Low ignition temperature

Description : Which of the following would require least amount of secondary air for combustion? (A) Coke breeze containing 25% ash and 2% volatile matter (B) Anthracite containing 10% volatile matter and 8% ash ... ash and 25% volatile matter (D) Semi-bituminous coal containing 25% ash and 20% volatile matter

Last Answer : (A) Coke breeze containing 25% ash and 2% volatile matter

Description : Fixed carbon in coal is defined as (A) That present in volatile matters (B) The total quantity of carbon present in the coal (C) Hundred minus the percentage of volatile matter, ash and moisture (D) The one which is present in the residue after combustion

Last Answer : (C) Hundred minus the percentage of volatile matter, ash and moisture

Description : Fat coals' are those coals which have very high (A) Caking capacity (B) Volatile matter content (C) Fusion point of its ash (D) Inherent moisture conten

Last Answer : (A) Caking capacity

Description : A coal with high ash content (A) Has higher calorific value (B) Is harder and stronger (C) Is not subjected to washing (D) Has low quantity of mineral matter

Last Answer : (B) Is harder and stronger

Description : The specific gravity of coal depends mainly on its __________ content. (A) Carbon (B) Volatile matter (C) Ash (D) Moisture

Last Answer : (C) Ash

Description : Ultimate analysis of coal determines its __________ content. (A) Carbon, hydrogen, nitrogen & sulphur (B) Carbon, ash, sulphur & nitrogen (C) Carbon, sulphur, volatile matter & ash (D) Carbon, volatile matter, ash & moisture

Last Answer : (A) Carbon, hydrogen, nitrogen & sulphur

Description : Proximate analysis of coal determines its __________ content. (A) Moisture, ash, sulphur & volatile matter (B) Moisture, volatile matter, ash & fixed carbon (C) Moisture, sulphur, nitrogen & fixed carbon (D) None of these

Last Answer : (B) Moisture, volatile matter, ash & fixed carbon

Description : Degree of carbonisation of coal during coke making can be roughly judged by the __________ of the coke produced. (A) Colour (B) Moisture content (C) Ash content (D) Volatile matter

Last Answer : (D) Volatile matter

Description : A coal with high __________ content, would ignite most easily. (A) Fixed carbon (B) Volatile matter (C) Ash (D) Oxygen

Last Answer : (B) Volatile matter

Description : Proximate analysis of coal determines its __________ content. (A) Moisture, ash, sulphur & volatile matter (B) Moisture & volatile matter (C) Moisture, sulphur, nitrogen & fixed carbon (D) None of these

Last Answer : (B) Moisture & volatile matter

Description : Ultimate analysis of coal determines its __________ content. (A) Carbon, hydrogen, nitrogen & sulphur (B) Carbon, ash, sulphur & nitrogen (C) Carbon, sulphur, volatile matter & ash (D) Carbon, volatile matter, ash & moisture

Last Answer : (C) Carbon, sulphur, volatile matter & ash

Description : The specific gravity of coal depends mainly on its __________ content. (A) Carbon (B) Volatile matter (C) Ash (D) Moisture

Last Answer : Option D

Description : Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if (A) It contains large amount of volatile matter (B) It is stored in tall heaps (C) Smaller fines are stored in large quantity (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : For long flame and easy ignition, the coal used should have (A) High volatile matter (B) Low ash (C) High calorific value (D) High ash

Last Answer : (A) High volatile matter

Description : Fat' coal means a coal having (A) Low calorific value (B) High volatile matter (C) Low ash content

Last Answer : (B) High volatile matter

Description : A coal having higher volatile matter content will necessarily have lower (A) Ash fusion temperature (B) Calorific value (C) Ignition temperature (D) Caking index

Last Answer : (C) Ignition temperature

Description : Coke compared to the coal from which it has been made, contains (A) Less volatile matter (B) More carbon (C) Greater percentage of ash (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : Mineral matter, 'M' and ash percentage 'A' in coal are roughly related as (A) M = 1.8 A (B) M = 0.5 A (C) M = 1.1 A (D) M = A

Last Answer : (C) M = 1.1 A

Description : Mineral matter content (M) and ash content (A) in coal are approximately related as (A) M = 1.1A (B) M = A (C) M = 1.5A (D) M = 2A

Last Answer : (A) M = 1.1A

Description : Washing of coal decreases its (A) Caking index (B) Mineral matter content (C) Ash content (D) Both (B) and (C)

Last Answer : (B) Mineral matter content

Description : A coal having high ratio of volatile matter to fixed carbon as compared to a coal having low ratio of volatile matter to fixed carbon (A) Is less liable to spontaneous combustion on storage (B) ... a shorter flame (C) Requires smaller combustion space and less secondary air (D) None of these

Last Answer : (D) None of these

Description : Which will have the least volatile matter and hence will be the most difficult to ignite? (A) Bituminous coal (B) Coke (C) Semi-bituminous coal (D) Anthracite

Last Answer : (B) Coke

Description : Assam (India) coals suffers mainly from the disadvantage of high __________ content. (A) Ash (B) Volatile matter (C) Sulphur (4-6%)

Last Answer : (C) Sulphur (4-6%)

Description : Pick out the correct statement. (A) Angle of repose is always greater than the angle of slide (B) A hopper is a small bin with a sloping bottom (C) A silo is a short height ... used as a 'modifying agent' (for activating or depressing the adsorption of filming agents) in froth floatation process

Last Answer : (B) A hopper is a small bin with a sloping bottom

Description : Ignition temperature decreases progressively from anthracite to lignite, because (A) Volatile matter content increases (B) Carbon content decreases (C) Moisture content increases (D) Ash content increases

Last Answer : (A) Volatile matter content increases

Description : Out of the following, which is the most important parameter for the blast furnace grade coke? (A) CSR & CRI (B) Ash content (C) Moisture content (D) Volatile matter content

Last Answer : (A) CSR & CRI

Description : Coals used for the generation of producer gas should have (A) High caking index (B) Low fusion point of ash (C) High volatile matter content (D) Very low ash content (8-10%)

Last Answer : (C) High volatile matter content

Description : Coal is heated in absence of air for 7 minutes at a temperature of about __________ °C, during its volatile matter determination for proximateanalysis. (A) 550 (B) 750 (C) 950 (D) 1150

Last Answer : (C) 950

Description : Volatile matter content in coking coal may be about __________ percent. (A) 1 (B) 7 (C) 22 (D) 46

Last Answer : (C) 22

Description : Pick out the wrong statement. (A) Indian coals on an average contain 25-30% ash as against 10-12% ash in imported coking coal (B) Ammonia is recovered in the form of ammonium sulphate in direct ... indicates poor caking properties of coal (D) Wash oil is used for scrubbing Benzol from coke oven gas

Last Answer : (C) A high swelling index number of coking coal indicates poor caking properties of coal

Description : The reason for excessive clinker formation in gas producers is the (A) Use of coal/coke containing a high % of fines and ash (B) Use of fuel having too low an ash fusion temperature (C) Development of hot spots in the fuel bed and an abnormally high rate of gasification (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : In coal washeries, three products namely the valuable product (i.e. clean/washed coal), discarded product (i.e. mineral matter) and an additional concentrated product called __________ is produced. (A) Concentrate (B) Tailing (C) Middling (D) None of these

Last Answer : (C) Middling

Description : Coal is pulverised before burning in large capacity boiler furnaces mainly to (A) Ensure its complete combustion (B) Facilitate easy ash removal (C) Enhance its calorific value (D) Provide trouble free operation

Last Answer : (A) Ensure its complete combustion

Description : Washability curve based on float and sink test enables an assessment to be made of the possibility of cleaning a coal fraction based on the (A) Density separation (B) Differential wettability (C) Size (D) Volatile matter content

Last Answer : (A) Density separation

Description : Fussain (A) Is friable, charcoal like substance (B) Has highest fixed carbon and lowest volatile matter content of all the four banded components of coal (C) Is non-coking, but when blended with highly coking ... its swelling and produces high strength coke on carbonisation (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : A coal having high amount of volatile matter (A) Would require smaller combustion chamber (B) Produces very little of tar and gas on carbonisation (C) Ignites easily and burns with long smoky flame (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Description : A coal having high amount of volatile matter (A) Would require smaller combustion chamber (B) Produces very little of tar and gas on carbonisation (C) Ignites easily and burns with long smoky flame (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

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

Last Answer : (D) Burns with short, bluish, yellow-tipped flame producing very little smoke

Description : The function of secondary combustion air is to (A) Pneumatically convey the pulverised coal (B) Completely burn the volatile matter (C) Burn the lumpy coal (D) None of these

Last Answer : (B) Completely burn the volatile matter

Description : Ratio of primary air to secondary air increases with increase in the rank of coal, because the (A) High rank coals have higher amount of volatile matter (B) Ratio of fixed carbon to volatile matter increases (C) Oxygen content progressively decreases (D) Calorific value of the coal increases

Last Answer : (B) Ratio of fixed carbon to volatile matter increases

Description : Pick out the wrong statement. (A) High concentration of oxygen in flue gas means high stack loss (B) Gaseous fuels require the least % excess air for complete combustion (C) The ratio of fixed carbon to ... coal is called its 'fuel ratio' (D) Calorific value of natural gas is more than that of LPG

Last Answer : (D) Calorific value of natural gas is more than that of LPG

Description : Cannel coal (A) Is non-coking (B) Has a high volatile matter content and burns with a luminous smoky flame (C) Is a non-banded coal which can be ignited easily with a match stick or candle flame, hence is so named (D) All (A), (B) and (C

Last Answer : (D) All (A), (B) and (C

Description : A coal having higher volatile matter content, has lower (A) Smoking tendency on burning (B) Coke oven gas yield on carbonisation (C) Chance of catching fire during storage in open space (D) Ignition temperature

Last Answer : (D) Ignition temperature

Description : The fuel ratio of a coal is (A) The ratio of its percentage of fixed carbon to that of volatile matter (B) Helpful in estimation of its rank (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) and (B)

Description : In low temperature carbonisation of coal, the (A) Yield of coke oven gas is 290 Nm3 /ton dry coal (B) Volatile matter in coke is zero (C) Temperature maintained is 700°C (D) Yield of tar is about 3% of dry coal

Last Answer : (C) Temperature maintained is 700°C

Description : Pick out the wrong statement. (A) Pulverised fuel can be completely burnt with less percentage of excess air compared to lump coal (B) Low grade coal can be used, but generally high volatile ... and atmosphere (oxidising or reducing) is easily possible with pulverised fuel firing (D) None of these

Last Answer : (D) None of these

Description : Pick out the wrong statement. (A) Angle of repose of coal increases with its increasing size (B) Specific gravity of coal increases with its increasing maturity (C) Refractive index and reflectance of ... of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal

Last Answer : (D) Specific heat of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal