Description : Pick out the correct statement. (A) Oxygen content decreases from lignite to bituminous coal as the coalification increases (B) The less the oxygen content, better is the coal, as it reduces the calorific value (C ... capacity of coal increases and the caking power decreases (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Low temperature oxidation of stored coal results in the (A) Decrease in its caking power & calorific value (B) Decrease in its carbon & hydrogen content (C) Increase in its oxygen content (D) All (A), (B) and (A)
Last Answer : (D) All (A), (B) and (A)
Description : Improper storage condition results in the weathering of coal and spontaneous combustion, which increases its (A) Caking index (B) Yield of carbonised products (C) Friability & oxygen content (D) Calorific value
Last Answer : (C) Friability & oxygen content
Description : Low temperature oxidation of coal during storage does not decrease its (A) Oxygen content (B) Caking power (C) Calorific value (D) None of these
Last Answer : (D) None of these
Description : Low temperature oxidation of coal resulting from bad storage conditions does not decrease its (A) Caking power (B) Calorific value (C) Hydrogen content (D) Oxygen content
Last Answer : (D) Oxygen content
Description : Bomb calorimeter can be used to determine the __________ of the coal. (A) Sulphur content (B) Calorific value (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : With increase in moisture content of coal, its (A) Calorific value increases (B) Caking properties diminish (C) Swelling during carbonisation becomes excessive (D) None of these
Last Answer : (B) Caking properties diminish
Description : Coke oven gas produced by high temperature carbonisation of coal (as compared to that produced by low temperature carbonisation), has (A) Higher calorific value (B) Lower hydrogen content (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (D) Neither (A) nor (B)
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 : 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 : __________ of the coal is the basis for Seylor's coal classification. (A) Proximate analysis (B) Ultimate analysis (C) Caking index (D) Calorific value
Last Answer : (B) Ultimate analysis
Description : The weathering index of a coal (A) Gives an idea of the fusion temperature of ash (B) Is related to its calorific value (C) Is a measure of its size stability, when stored & exposed to weather (D) Is a measure of its caking tendency
Last Answer : (C) Is a measure of its size stability, when stored & exposed to weather
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 : With increase in moisture content of coal, its (A) Calorific value increases sometimes (B) Bulk density always decreases (C) Clinkering tendency during combustion increases (D) None of these
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 : As the equilibrium moisture content of the coal increases, its (A) Calorific value increases (B) Swelling number decreases (C) Swelling number increases (D) Bulk density decreases
Last Answer : (B) Swelling number decreases
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 : With increase in carbide/graphite ratio in cast iron, its (A) Hardness & brittleness increases (B) Ductility decreases (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Initial pressure of oxygen introduced into the 'bomb' of the bomb calorimeter for determination of calorific value of coal/fuel oil may be around __________ atm. (A) 3-5 (B) 25-30 (C) 60-65 (D) 95-100
Last Answer : (B) 25-30
Description : Coal tar fuels (CTF) as compared to petroleum based fuel oils have higher (A) Calorific value (B) Higher C/H ratio (C) Sulphur content (D) Difference in gross & net calorific value
Last Answer : (B) Higher C/H ratio
Description : In any spontaneous process, the __________ free energy decreases. (A) Helmholtz (B) Gibbs (C) Both ‘a’ & ‘b’ (D) Neither 'a' nor 'b'
Last Answer : (C) Both ‘a’ & ‘b’
Description : The 'transition temperature' for ductile to brittle behaviour of steel increases with increase in the __________ content in steel. (A) Carbon (B) Manganese (C) Both 'a' nor 'b' (D) Neither 'a' nor 'b'
Last Answer : (A) Carbon
Description : Washing of coal (A) Reduces its sulphur and ash content (B) Controls its ash fusibility and increases its calorific value (C) Improves its coking properties (D) All (A), (B) and (C)
Description : Weathering of coal during storage causes (A) Reduction in coal size (B) Increase in its friability (C) Decrease in its caking capacity (D) All (A), (B) and (C)
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 gasifier operating at 20 atm. (e.g. Lurgi gasifier) as compared to one operating at atmospheric pressure (e.g. Kopper-Totzek or Winkler gasifier) will produce a gas having (A) Higher ... calorific value (B) Higher carbon monoxide content (C) Lower carbon dioxide content (D) None of these
Last Answer : (A) Higher methane content and thus higher calorific value
Description : . A coal having high volatile matter content will (A) Give less yield of tar and gas on carbonisation (B) Burn with a small non-smoky flame (C) Have a very high calorific value (D) None of these
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 : In high temperature carbonisation of coal compared to low temperature carbonisation (A) Yield of ammonia is less (B) Aromatic content of tar is low (C) H2 content in the coke oven gas is more (D) Calorific value of the coke oven gas is lower
Last Answer : (C) H2 content in the coke oven gas is more
Description : During its calorific value determination by bomb calorimeter, coal is combusted by (A) Air (B) Oxygen (C) Oxygen enriched air (D) None of these
Last Answer : (C) Oxygen enriched air
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 : During constant rate period, the rate of drying decreases with the (A) Decrease in air temperature (B) Increase in air humidity (C) Both (A) and (B) (D) Neither (A) nor (B)
Description : With increase in temperature, the equilibrium __________ rises in case of endothermic reaction. (A) Constant (B) Conversion (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Conversion
Description : For a constant volume process __________ by the system is used only to increase the internal energy. (A) Heat absorbed (B) Work done (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Work done
Description : Softening temperature of coal ash is a measure of the __________ of coal. (A) Caking tendency (B) Coking tendency (C) Clinkering tendency (D) Size stability
Last Answer : (C) Clinkering tendency
Description : A travelling grate stoker is meant for the efficient burning of __________ coal. (A) Caking (B) Pulverised (C) Non-caking (D) High ash
Last Answer : (C) Non-caking
Description : In a packed absorption tower, if the equilibrium and operating lines are both straight lines, then the ratio, HETP/HTUOG __________ the absorption factor. (A) Increases with increase in (B) Is one at unity value of (C) Both (A) and (B) (D) Neither (A) nor (B)
Description : Sulphur in metallurgical coal (A) Contributes to its heating value (B) Affects the quality of steel produced as cracks develop on the surface while rolling the steel (C) Both (A) and (B) (D) Neither (A) nor (B)
Description : With diminishing cross-sectional area in case of subsonic flow in a converging nozzle, the (A) Velocity increases (B) Pressure decreases (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : Refractive index of a petrofuel which is the ratio of velocity of light in air to its velocity in the petrofuel gives an indication if its (A) Molecular weight (B) Aromatics content (C) Both ‘a’ & ‘b’ (D) Neither ‘a’ nor ‘b’
Last Answer : (C) Both ‘a’ & ‘b
Description : Change of heat content when one mole of compound is burnt in oxygen at constant pressure is called the (A) Calorific value (B) Heat of reaction (C) Heat of combustion (D) Heat of formation
Last Answer : (C) Heat of combustion
Description : Which of the following statement (s) regarding India's coal reserves is/are true ? 1. Over 90 percent of total reserves are located in the valleys of Son, Damodar, Mahanadi and Godavari 2. Indian coal reserves are characterised ... reserves (a) I only (b) I and III (c) II and III (d) I, II and III
Last Answer : Ans: (c)
Description : Aniline point is the (A) Characteristic property of diesel & lubricating oils (B) Measure of aromatic content of oil (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B
Description : Oil produced by solvent extraction (A) Has low free fatty acid content (B) Is odourless (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : The important dimensional group involved in the power requirement calculation in mixing operation is the __________ number. (A) Reynold's (B) Froude (C) Both (A) & (B) (D) Neither (A) nor (B)
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 : A catalyst in a chemical reaction __________ free energy change in the reaction. (A) Increases (B) Decreases (C) Either (A) or (B); depends on the type of catalyst (D) Neither (A) nor (B)
Last Answer : (C) Either (A) or (B); depends on the type of catalyst
Description : Calorific value of bituminous coal may be around __________ Kcal/kg. (A) 500 (B) 1500 (C) 6500 (D) 20000
Last Answer : (C) 6500
Description : Calorific value of coke even gas produced by low temperature carbonisation of coal is about __________ Kcal/Nm3 . (A) 4000 (B) 2500 (C) 6500 (D) 10000
Description : Calorific value of a typical dry anthracite coal may be around __________ Kcal/kg. (A) 1000 (B) 4000 (C) 8000 (D) 15000
Last Answer : (C) 8000