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 : 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 : A coal with high ash content is undesirable, as (A) It is abrasive to the coal pulveriser (i.e. ball mill) and the combustion chamber (B) The ash in molten condition gets absorbed in the pores of the ... and stick to the boiler tubes thereby reducing the heat transfer (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : "Micum Index" of a coke is a measure of its (A) Reactivity (B) Porosity (C) Bulk density (D) Hardness & strength
Last Answer : (D) Hardness & strength
Description : A good quality coal should have (A) Low fusion point of ash (B) High ash content (C) High sulphur (D) None of these
Description : A good quality coal should have (A) Low fusion point of ash (B) High ash content (C) High sulphur content (D) None of these
Description : Washing of coal (A) Reduces its ash & sulphur content (B) Improves its coking properties (C) Increase the fusion point of its ash by removing chlorine compounds (D) All (A), (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 : 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 : 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 : 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 : 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 : High amount of sulphur and phosphorous in coke causes (A) Decrease in its calorific value (B) Increase in its strength (C) Brittleness of steel made by using it (D) None of these
Last Answer : (C) Brittleness of steel made by using it
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 : 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 : LSHS is a type of furnace oil, which (A) Is more viscous than high viscosity furnace oil (HVFO) (B) Stands for low sulphur heavy stock (C) Is an ideal fuel for metallurgical furnaces due to its lower sulphur content (< 1%) (D) All (A), (B) and (C)
Description : Low temperature carbonisation of coal produces (A) Metallurgical coke (B) Soft coke (C) Very low calorific value coke oven gas (D) No by-products
Last Answer : (B) Soft coke
Description : The advantages of firing pulverised coal in the furnace lies in the fact that, it (A) Permits the use of high ash content coal (B) Permits the use of low fusion point ash coal (C) Accelerates the burning rate and economises on fuel consumption (D) All (A), (B) and (C)
Last Answer : (C) Accelerates the burning rate and economises on fuel consumption
Description : The advantage of firing pulverised coal in the furnace lies in the fact, that it (A) Permits the use of high ash content coal (B) Permits the use of low fusion point ash coal (C) Accelerates the burning rate and economises on fuel combustion (D) All (A), (B) and (C)
Last Answer : (C) Accelerates the burning rate and economises on fuel combustion
Description : Washing of coal does not reduce its (A) S & P content (B) Heating value (C) Fusion point of ash (D) None of these
Description : Volatile matter content of metallurgical coke may be around __________ percent. (A) 1-2 (B) 10-15 (C) 22-26 (D) 30-33
Last Answer : (A) 1-2
Description : During combustion of coal on grate, clinker formation is increased by the (A) Use of thick fire bed (B) Low fusion point of ash (< 1100° C) (C) Use of preheated primary air (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
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 : Fusion point of coal ash increases with increase in its __________ content. (A) Iron sulphate (B) Iron silicate (C) Lime and magnesia (D) All (A), (B) and (C)
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 : In producer gas making furnace, steam is added along with air to mainly control the (A) Fusion of coal ash & clinker formation (B) C. V. of producer gas (C) Temperature of producer gas (D) Tar content in producer gas
Last Answer : (A) Fusion of coal ash & clinker formation
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 : Coke having higher porosity has (A) Lower bulk density (B) Lower strength (C) Higher reactivity (D) All (A), (B) and (C)
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 : Presence of phosphorous in metallurgical coal (A) Is not undesirable (B) Reduces its calorific value (C) Badly affects the quality of steel
Last Answer : (C) Badly affects the quality of steel
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
Description : A good coking coal should have high __________ content. (A) Ash (B) Sulphur & phosphorus (C) Moisture (D) None of these
Description : Roasting of metallurgical ores is done mainly to (A) Dehydrate it (B) Sinter the ore (C) Remove CO2 & H2O (D) Remove arsenic & sulphur
Last Answer : (D) Remove arsenic & sulphur
Description : Critical Air Blast (CAB) value of coke is a direct measure of its (A) Reactivity (B) Hardness (C) Strength (D) None of these
Last Answer : (A) Reactivity
Description : M10 index of coke indicates its (A) Compressive strength (B) Hardness (C) Abrasion resistance (D) Impact strength
Last Answer : Option C
Description : M10 index of coke indicates its (A) Compressive strength (B) Hardness (C) Abrasion resistance (D) Impact strength Answer: Option C
Description : Combustion of pulverised fuel (A) Requires larger combustion chamber than rich gaseous fuel (B) In a metallurgical furnace does not contaminate the product in the furnace by ash from fuel (C) Suppresses the discharge of fine dust and grit into atmosphere (D) All (A), (B) and (C)
Last Answer : (A) Requires larger combustion chamber than rich gaseous fuel
Description : __________ is added in low carbon steel to raise its yield point. (A) Sulphur (B) Phosphorous (C) Silicon (D) Manganese
Last Answer : (D) Manganese
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 : 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 : Primary designation of steel is based on its (A) Hardness & tensile strength (B) Carbon content (C) Iron content (D) Alloying elements content
Last Answer : (D) Alloying elements content Sh
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 : 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 : ________ content of the phosphate rock is the pollutant of primary interest in a phosphatic fertiliser plant. (A) Calcium (B) Fluorine (C) Phosphorous (D) Sulphur
Last Answer : (B) Fluorine
Description : Quantity of coke produced from metallurgical coal may be around __________ percent. (A) 30 (B) 50 (C) 75 (D) 95
Last Answer : (C) 75
Description : Shatter index of metallurgical coke on 2 inches and 0.5 inch screen should be respectively around __________ percent. (A) 80 and 97 (B) 95 and 100 (C) 40 and 70 (D) 25 and 97
Last Answer : (A) 80 and 97
Description : Desirable "Micum Index" values of metallurgical coke are (A) M40 > 78% and M10 < 10% (B) M40 > 4% and M10 < 80% (C) M40 > 10% and M10 < 78% (D) M40 > 98% and M10 < 2%
Last Answer : (A) M40 > 78% and M10 < 10%