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 : Specific gravity of hot metal (pig iron) is __________ times that of the blast furnace slag. (A) 2 (B) 3 (C) 0.8 (D) 6
Last Answer : (B) 3
Description : Volume of blast furnace slag is about __________ times the volume of hot metal (pig iron) of the same weight (A) 1.5 (B) 3 (C) 5
Last Answer : Option B
Description : Which furnace employs an I.D. fan for the removal of flue gases from the furnace? (A) Coke oven (B) Blast furnace stoves (C) Beehive coke oven (D) High pressure boiler
Last Answer : (D) High pressure boiler
Description : The refractory lining of the bottom in a basic electric arc furnace is made of (A) Silica (B) Alumina (C) Magnesia (D) Fireclay
Last Answer : Option C
Description : Heat transfer rate to the charge/stock in a furnace does not depend upon the (A) Type of fuels viz. solid, liquid or gaseous (B) Flue gas temperature (C) Emissivity of refractory walls (D) Initial temperature of the charged stock
Last Answer : (A) Type of fuels viz. solid, liquid or gaseous
Description : Refractory bricks having high thermal conductivity is desirable, when it is to be used in the (A) L.D. converter (B) Blast furnace (C) Rotary kiln (D) Recuperator
Last Answer : (D) Recuperator
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 : Pick out the wrong statement. (A) Dry process is used for the manufacture of cement, when the raw material is blast furnace slag (B) Portland cement is made employing wet process (C) Gypsum is added to Portland cement to lengthen its setting time (D) None of these
Last Answer : (D) None of these
Description : Limestone is added in the blast furnace (during pig iron manufacture) to (A) Form slag by combining with impurities (B) Supply heat by undergoing exothermic reaction with impurities (C) Reduce the coke consumption (D) Reduce slag viscosity
Last Answer : Option A
Description : Basicity [%Cao + %MgO + %SiO2) of the slag in Indian blast furnace is in the range of (A) 0.7-1.0 (B) 1.1-1.4 (C) 1.5 - 1.8
Description : Pick out the wrong statement. (A) A slight haze at the top of chimney indicates good combustion in the furnace (B) A bag filter incurs very small pressure drop and is very efficient for ... dust collection equipment for removal of submicronic dust particles present in flue gas (D) None of these
Last Answer : (B) A bag filter incurs very small pressure drop and is very efficient for removal of submicronic dust particles from flue gases at very high temperature
Description : Out of the following fuels used in a furnace exhausting flue gas at a temperature of 600°C, the percentage stack loss will be maximum in case ofcomplete combustion of (A) Furnace oil with air (B) Furnace oil with oxygen (C) Blast furnace gas with air (D) Blast furnace gas with oxygen
Last Answer : (C) Blast furnace gas with air
Description : The slag formed in the blast furnace during the extraction of iron from haematite is
Last Answer : The slag formed in the blast furnace during the extraction of iron from haematite is A. `Ca_(3)(PO_(4))_(2)` ... (3)` C. `FeSiO_(3)` D. `MnSiO_(3)`
Description : In the extraction of copper, the slag formed in the blast furnace is
Last Answer : In the extraction of copper, the slag formed in the blast furnace is A. `CaSiO_(3)` B. `FeSiO_(3)` C. `FeSiO_(3)` D. `MnSiO_(3)`
Description : What is the viscosity of slag of blast furnace?
Last Answer : What is the answer ?
Description : You are asked to construct a massive dam, the type of cement you will use, is (A) Ordinary Portland cement (B) Rapid hardening cement (C) Low heat cement (D) Blast furnace slag cement
Last Answer : Answer: Option C
Description : For the construction of thin R.C.C. structures, the type of cement to be avoided, is (A) Ordinary Portland cement (B) Rapid hardening cement (C) Low heat cement (D) Blast furnace slag cement
Last Answer : Answer: Option D
Description : For road pavements, the cement generally used, is (A) Ordinary Portland cement (B) Rapid hardening cement (C) Low heat cement (D) Blast furnace slag cement
Last Answer : Answer: Option B
Description : Blast furnace slag cement concrete requires ___________time for shuttering and curing. (a) Less (b) More (c) Medium (d) All the above
Last Answer : (b) More
Description : For mass concrete work, the type of cement preferable is [ A ] Ordinary Portland cement [ B ] Rapid hardening cement [ C ] Low heat cement [ D ] Blast furnace slag cement
Last Answer : [ C ] Low heat cement
Description : For road pavements, the cement generally used, is [ A ] Ordinary Portland cement [ B ] Rapid hardening cement [ C ] Low heat cement [ D ] Blast furnace slag cement
Last Answer : [ A ] Ordinary Portland cement
Description : In Portland Blast furnace slag cement, the blast furnace slag content shall not exceed [ A ] 50% [ B ] 65% [ C ] 80% [ D ] 90%
Last Answer : [ B ] 65%
Description : State the uses of fly ash and blast furnace slag.
Last Answer : I) Fly ash The various uses of fly ash are: 1) Concrete production, as a partial substitute material for Portland cement. 2) For the construction of embankments and other structural fills. 3) For ... and water proofing. 5) It is used as insulation in mineral wool, in rail road ballast etc.
Description : Write two uses of each : (i) Fly ash (ii) Blast furnace slag
Description : Pick out the wrong statement. (A) Cold cracking of a weld is due to the presence of hydrogen gas in the weld (B) True stress is given by, σ = σE (1 + εE), where σE and εE ... in the iron blast furnace (D) High residual stress at the surface is beneficial for fatigue properties of a material
Description : Dephosphorization of molten pig iron is favoured by (A) Oxidising and basic slag (B) Reducing and basic slag (C) High activity co-efficient of phosphorous in metal (D) Oxidising and neutral slag
Description : Which of the following is not an additive for flue gases from furnace to reduce its dew-point? (A) Ammonia (B) Fine dolomite (C) Alkaline powders (D) None of these
Description : The heat recoverable from flue gases of furnaces depends on the (A) Thermal efficiency of furnace (B) Quantity of flue gases (C) Flue gas temperature drop through the furnace (D) All (A), (B) and (C)
Description : Furnace aerodynamics is related to the __________ in the furnace. (A) Movement of gases (B) Measurement of flue gas volume (C) Temperature control
Last Answer : (A) Movement of gases
Description : Which of the following is not a continuous waste heat recovery equipment from the flue gases going out of furnace? (A) Economiser (B) Regenerator (C) Ceramic recuperator (D) Waste heat boiler
Last Answer : (B) Regenerator
Description : In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on the (A) Rate of firing and emissivity of flame (B) Thermal conductivity of the charge & ... (C) Nature of process; whether batch, continuous or intermittent (D) All (A), (B) and (C)
Description : Incomplete combustion of fuel in the furnace is judged by high __________ of the flue gases. (A) CO content (B) Dew point (C) CO2 content (D) O2 content
Last Answer : (A) CO content
Description : Which of the following fuel gases is heavier than air? (A) Blast furnace gas (B) Coke oven gas (C) Natural gas (D) Water gas
Last Answer : (A) Blast furnace gas
Description : Which of the following fuel gases will require maximum amount of air for combustion of 1 Nm3 gas? (A) Blast furnace gas (B) Natural gas (C) Producer gas (D) Water gas
Last Answer : (B) Natural gas
Description : . Which of the following fuel gases contains maximum amount of carbon monoxide? (A) Coke oven gas (B) Water gas (C) Blast furnace gas (D) L.D. converter gas
Last Answer : (D) L.D. converter gas
Description : Find false statement about effect of sulphur in fuel? (A) It has heating value (B) It helps in electrostatic precipitation of ash in flue gases (C) It leads to corrosion of air heaters, ducting, etc. if flue gas exit temperature is low (D) It erodes furnace walls
Last Answer : (D) It erodes furnace walls
Description : Which of these is an output of a ‘Furnace’? a. Fuel gas b. Cool Air c. Flue gases d. Water Vapor
Last Answer : c. Flue gases
Description : Flue gases coming out from furnace is first going through a) Turbine b) Economizer c) Air pre-heater d) Chimney
Last Answer : Ans: Economizer
Description : Coke oven gas after passing through return electrostatic tar precipitator (RETP) is used for the (A) Hot scarfing of steel slabs (B) Mixing with blast furnace gas (C) Coke oven battery heating (D) Steel ladle drying
Last Answer : (C) Coke oven battery heating
Description : Sensible heat of hot industrial flue gases cannot be recovered by a/an (A) Economiser (B) Regenerator (C) Ceramic recuperator (D) None of these
Description : Water-tube boiler is the one, in which (A) Water passes through tubes and flue gases around it (B) Tube carrying hot flue gases are immersed in a pool of water (C) Tubes are placed in vertical position (D) None of these
Description : In the blast furnace, incorporation of water vapour in the blast gives the following effect. (A) Increases the reducing potential of the gas (B) Increases the flame temperature (C) No significant change occurs (D) Increases the hydrogen content in the metal
Last Answer : (A) Increases the reducing potential of the gas
Description : Which of the following bricks are used for lining of furnaces? (A) Over-burnt bricks (B) Under-burnt bricks (C) Refractory bricks (D) First class bricks
Description : Suspended solid present in the waste water generated in blast furnace gas cooling and cleaning plant is removed by (A) Biological oxygen pond (B) Radial settling tank (thickener) using coagulant (lime & ferrous sulphate) (C) Lagoons (D) Filtration
Last Answer : (B) Radial settling tank (thickener) using coagulant (lime & ferrous sulphate)
Description : Limestone addition in the blast furnace is done to flux __________ present in the raw materials. (A) SiO2 (B) Al2O3 (C) MnO2 (D) P
Last Answer : Limestone addition in the blast furnace is done to flux __________ present in the raw materials. (A) SiO2 (B) Al2O3 (C) MnO2 (D) P
Description : A mixture of haematite, coke and limestone on heating in blast furnace gives molten iron metal. This is known as
Last Answer : A mixture of haematite, coke and limestone on heating in blast furnace gives molten iron metal. ... Smelting B. Calcination C. Roasting D. Liquition
Description : The cement whose strength is a little lower than the ordinary cement during the first three months but attains afterwards the same strength, is known as (A) Low-heat Portland cement (B) Rapid hardening Portland cement (C) Portland blast slag cement (D) Portland pozzolana cement
Last Answer : Answer: Option A
Description : Tank furnace used for melting of glass is made of (A) Mild steel (B) Cast iron (C) Refractory blocks (D) Stainless steel
Last Answer : (C) Refractory blocks