Description : Purity of coke means that, it is high in carbon and low in (A) Volatiles (B) Ash (C) Iron (D) Moisture
Last Answer : (A) Volatiles
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 : What are the major constituents of typical fly ash particles generated from the combustion of coal? w) acidic and basic oxides x) trace elements y) unburned carbon z) sulfates and phosphates
Last Answer : ANSWER: W -- ACIDIC AND BASIC OXIDES
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 : Higher percentage of ash in coal meant for the production of metallurgical grade coke (A) Decreases the hardness of coke (B) Decreases the abrasion resistance of coke (C) Causes brittleness in steel (D) None of these
Last Answer : (D) None of these
Description : Commercial production of soda ash by Solvay process requires limestone, __________ as raw materials. (A) Coke and sand (B) Brine and coal (C) Coke and caustic soda (D) None of these
Last Answer : (B) Brine and coal
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 : The specific gravity of coal depends mainly on its __________ content. (A) Carbon (B) Volatile matter (C) Ash (D) Moisture
Last Answer : (C) Ash
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 : 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 : 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
Last Answer : (C) Carbon, sulphur, volatile matter & ash
Last Answer : Option D
Description : A good metallurgical coke (A) Should have high porosity (B) Should be brittle (C) Must contain moderate quantities of ash, moisture, sulphur and volatile matters (D) Should have low fusion point of its ash
Last Answer : (A) Should have high porosity
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)
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 : Pick out the wrong statement. (A) Percentage of ash in coke produced from medium coking coal is more than that in coal (B) The calorific value (kcal/Nm3 ) of coke oven gas reduces on ... plants in India at Talcher (Orissa) and Ramagundam (A.P) employ Kopper-Totzek process of coal gasification
Last Answer : (C) Ash is normally removed as 'fly-ash' in Kopper-Totzek process of coal gasification
Description : Ash content in the coke produced from a coking coal having 20% ash may be around __________ percent. (A) 6 (B) 12 (C) 18 (D) 24
Last Answer : (D) 24
Description : Which of the following is unsuitable fuel for producer gas manufacture? (A) Coke (B) Anthracite (C) Coal having low fusion point of its ash (D) Coal having high fusion point of its ash
Last Answer : (C) Coal having low fusion point of its ash
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 : A good coking coal should have high __________ content. (A) Ash (B) Sulphur & phosphorus (C) Moisture (D) None of these
Description : Pulverised coal used in boiler firing need not have (A) Less moisture content (B) High fusion point of its ash (C) High bulk density (D) Lower ash conten
Last Answer : (B) High fusion point of its ash
Description : Presence of free moisture in coal during its high temperature carbonisation (A) Reduces the coking time (B) Protects the volatile products from pyrolysis (cracking) in the presence of hot coke and hot oven walls (C) Increases the loss of fine coal dust from the ovens when charging (D) None of these
Last Answer : (B) Protects the volatile products from pyrolysis (cracking) in the presence of hot coke and hot oven walls
Description : Coke used for the production of calcium carbide should have (A) Low ash content (B) Low ignition temperature (C) High electrical resistivity (D) All (A), (B) and (C)
Description : Commercial production of calcium carbide requires limestone and __________ as raw materials. (A) Coke (B) Sand (C) Soda ash (D) Fuel oil
Last Answer : (B) Sand
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 : Which of the following constituents present in petroleum is responsible for ash formation? (A) Nitrogen compounds (B) Organometallic compounds (C) Sulphur compounds (D) Oxygen compounds
Last Answer : (C) Sulphur compounds
Description : The major constituents of glass are (A) Lime, clay and soda ash (B) Sand, lime and soda ash (C) Silica, alumina and clay (D) Silica, alumina and soda ash
Last Answer : (B) Sand, lime and soda ash
Description : 64-132) rank coal (ASTM) means a coal with 64% (A) Fixed carbon and having a heating value around 13, 200 BTU/1b (B) Ash and heating value around 13, 200 BTU/1b (C) Fixed carbon and heating value around 132 BTU/1b (D) None of these
Last Answer : (A) Fixed carbon and having a heating value around 13, 200 BTU/1b
Description : 64-132) rank coal (ASTM) means a coal with 64% (A) Fixed carbon and having a heat value of 13, 200 BTU/1b (B) Ash and a heating value of 13, 200 BTU/1b (C) Fixed carbon and a heating value of 132 BTU/1b (D) None of these
Last Answer : (A) Fixed carbon and having a heat value of 13, 200 BTU/1b
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 : CO & H2 are the constituents of (A) Producer gas (B) Water gas (C) Coke oven gas (D) All (A), (B) and (C)
Description : Which of the following is not a commercially used feed-stock for the production of ammonia synthesis gas? (A) Water (B) Naphtha (C) Tar (D) Coal/coke oven gas
Last Answer : (C) Tar
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)
Description : The difference between total carbon and fixed carbon of coal will be minimum in case of (A) Lignite (B) Bituminous coal (C) Anthracite (D) High temperature coke (V.M < 0.5%)
Last Answer : (D) High temperature coke (V.M < 0.5%)
Description : In high temperature carbonisation (as compared to low temperature carbonisation) of coal (A) Coke oven gas yield is more (B) Tar yield is less but free carbon in tar is more (C) Calorific value of coke oven gas is less (D) All (A), (B) and (C)
Description : Anthracite can be used for (A) Recarbonising steel (B) Making carbon electrodes (C) Blending with highly coking coal to check its swelling which helps in saving coke even walls from damage and to produce high strength coke (D) All (A), (B) and (C)
Description : With increase in the temperature of carbonisation of coal (A) Hydrogen content of coke oven gas increases due to cracking ofhydrocarbons (B) Methane content in the coke oven gas decreases and carbon monoxide content increases ( ... compensated by increase in CO & H2 content (D) All (A), (B) and (C)
Description : In low temperature carbonisation of coal as compared to high temperature carbonisation __________ produced is less. (A) Difference in gross & net calorific value of the coke oven gas (B) Free carbon content in tar (C) Yield percentage of coke (D) Yield of ammonia present in coke oven gas
Last Answer : (A) Difference in gross & net calorific value of the coke oven gas
Description : The radioactive pollution may result from: 1. medical waste 2. coal ash 3. production of nuclear arsenal 4. mining of uranium 5. decommissioning of nuclear weapons The correct causes are: (a) 1, 3 and 4 only (b) 1, 3, 4 and 5 only (c) 2, 3, 4 and 5 only (d) 1, 2, 3, 4 and 5
Last Answer : Ans:(b)
Description : Which of the following is the most important deterrents to an extended use of pulverised coal in boiler firing? (A) Ash disposal problem (B) Excessive fly ash discharge from the stack (C) Higher power consumption in its transportation (D) Erosion of induced draft fan blades
Last Answer : (A) Ash disposal problem
Description : Which of the following is the most important deterrents to an extended use of pulverised coal in boiler firing? (A) Ash disposal problem (B) Excessive fly-ash discharge from the stack (C) High power consumption in its transportation (D) Erosion of induced draft fan blades
Description : Explain higher and lower calorific value of a coal having following composition by mass Carbon 81%,Hydrogen 7%, Oxygen 8%,Nitrogen 2.5%, sulphur 1.5% and remaining is ash
Last Answer : Carbon C = 81% = 0.81 Hydrogen = H2 = 7% = 0.07 Oxygen = O2 = 8% = 0.08 Nitrogen = N = 2.5% = 0.025 Sulphur = S =1.5% = 0.015 Ash = 2.5% = 0.025 Dulong's formula: H.C.V. of coal = 33800 C + 144500 ... = H.C.V.- 9H2 x 2442 KJ / Kg = 36187.5- 9 x 0.07 x 2442 L.C.V. of coal = 34649.04 KJ / Kg
Description : Increase in ash content of blast furnace coke (A) Reduces its consumption in the furnace (B) Increases its consumption in the furnace (C) Does not affect its consumption in the furnace (D) Decreases its hardness and abrasion resistance
Last Answer : (B) Increases its consumption in the furnace
Description : High ash coals (A) Are soft & friable (poor strength and size stability) (B) Require longer time of carbonisation as ash offers resistance to heat transfer (C) Produce larger quantity of coke oven gas (D) None of these
Last Answer : (A) Are soft & friable (poor strength and size stability)
Description : A good metallurgical coke should have very low (A) Sulphur & phosphorous content (B) Porosity (C) Fusion point of its ash (D) Hardness & strength
Last Answer : (A) Sulphur & phosphorous content
Description : High ash containing coke (A) Produces more slag when used in the blast furnace (B) Has poor strength and abrasion resistance (C) Is desirable in producer gas manufacture (D) None of these
Last Answer : (A) Produces more slag when used in the blast furnace
Description : Which of the following coke has the least percentage of ash? (A) Petroleum coke (B) Beehive coke (C) Foundry coke (D) Metallurgical coke
Last Answer : (A) Petroleum coke
Description : Raw materials for 'Solvay Process' for manufacture of the soda ash are (A) Salt, limestone and coke or gas (B) Ammonia, salt and limestone (C) Ammonia limestone and coke (D) None of these
Last Answer : (A) Salt, limestone and coke or gas