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)

1 Answer

Answer :

(D) All (A), (B) and (C)

Related questions

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)

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

Description : A good coking coal should have high __________ content. (A) Ash (B) Sulphur & phosphorus (C) Moisture (D) None of these

Last Answer : (D) None of these

Description : Washing of coal does not reduce its (A) S & P content (B) Heating value (C) Fusion point of ash (D) None of these

Last Answer : (D) None of these

Description : A good quality coal should have (A) Low fusion point of ash (B) High ash content (C) High sulphur (D) None of these

Last Answer : (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

Last Answer : (D) None of these

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 : 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 : 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)

Last Answer : (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 : During coking of coal, the ash content (percentage) (A) Increases (B) Decreases (C) Remain constant (D) None of these

Last Answer : (A) Increases

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 : Froth floatation is used for (A) Washing fine coal dust (< 0.5 mm size) (B) Washing lump coal (> 80 mm size) (C) Removing ash from the coal based on difference in specific gravity of coal and ash

Last Answer : (A) Washing fine coal dust (< 0.5 mm size)

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 : 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 : 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 : 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 : 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 : 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

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 : 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 : 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 : 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 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 : 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 : Fly ash when added to concrete [ A ] Acts as aggregates [ B ] Acts as pozzolona [ C ] Improves appearance [ D ] Reduces setting time

Last Answer : [ B ] Acts as pozzolona

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 : 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 : Preheating of coal charge for the coke ovens reduces the (A) Time of carbonisation (B) Yield of gas and tar (C) Fuel consumption in coking (D) All (A), (B) and (C)

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

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 : 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 : Fusion point of coal ash generally varies from 1000 to 1700° C. Ash having fusion point less than __________ °C is liable to form clinker. (A) 1100 (B) 1250 (C) 1350 (D) 1400

Last Answer : (A) 1100

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 : 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 : 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 : 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 : 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 : 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 : 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 correct statement. (A) Hot worked materials are subjected to annealing to remove internal stresses (B) Annealing of steel hardens it slightly (C) Normalising of a material induces stresses (D) Tempering of a material improves ductility & toughness but reduces hardness & brittleness

Last Answer : (D) Tempering of a material improves ductility & toughness but reduces hardness & brittleness Share

Description : High sulphur content in a fuel __________ of the flue gases. (A) Decreases the dew point (B) Increases the dew point (C) Reduces the combustion efficiency by limiting the permissible temperature reduction (D) Both (B) and (C)

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

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 : Bleaching powder is made from - (1) Sulphur dioxide and gypsum (2) Chlorine and Charcoal (3) Soda ash and lime (4) Lime and Chlorine

Last Answer : (4) Lime and Chlorine Explanation: The gas which is used in the preparation of bleaching powder is chlorine. It is a mixture of lime and calcium chloride.

Description : Which adsorbent is used for removing sulphur compounds (S Q, H2S, RSH etc.) removal from coke oven gas in by-products recovery plant? (A) Silica gel (B) Diatomaceous earth (C) Basalt (D) Bog iron (i.e., moist ferric hydroxide)

Last Answer : (D) Bog iron (i.e., moist ferric hydroxide)

Description : Which furnace burns low-ash fusion coal and retains most of the coal ash in the slag?

Last Answer : Cyclone furnace.

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 : Bright coal (A) Contains more than 90% durain (B) Contains more than 90% fussain (C) Contains mainly vitrain & clarain and is generally coking (D) Is non-coking

Last Answer : (C) Contains mainly vitrain & clarain and is generally coking