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 : 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 : Coal is pulverised before burning in large capacity boiler furnaces mainly to (A) Ensure its complete combustion (B) Facilitate easy ash removal (C) Enhance its calorific value (D) Provide trouble free operation
Last Answer : (A) Ensure its complete combustion
Description : Which of the following quantities has the GREATEST influence on the overall efficiency of a conventional (Rankine cycle) electric generating station burning fossil fuels? w) steam temperature at the steam turbine ... pressure at the steam turbine inlet z) pounds of ash and sulfur per pound of fuel
Last Answer : ANSWER: W -- STEAM TEMPERATURE AT THE STEAM TURBINE INLET
Description : Use of pulverised coal in boilers provides (A) Higher calorific value (B) Better combustion (C) Smokeless burning (D) Less erosion on furnace wall
Last Answer : (B) Better combustion
Description : Use of pulverised coal in boiler furnace provides (A) High calorific value (B) Better combustion (C) Smokeless burning (D) Less erosion on furnace walls
Description : What is coal ash?
Last Answer : I assume that by the name that would be the leftover ash from a coal fire (such as from a coal powered electric generating plant) mixed with water to form a slurry.
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 : Out of the following which one is not a unconventional source of energy ? (A) Tidal power (B) Geothermal energy (C) Nuclear energy (D) Wind power. Ans: C 30. Pulverized coal is (A) coal free from ash (B) non-smoking coal (C) coal which bums For long time (D) coal broken into fine particles
Last Answer : Ans: D
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 : Coal ash (or cinder) is used in initial stages of a new construction of railway for A. Wooden sleeper B. Steel sleeper C. Cast iron sleeper D. None of These
Last Answer : A [Wooden sleeper]
Description : Which furnace burns low-ash fusion coal and retains most of the coal ash in the slag?
Last Answer : Cyclone furnace.
Description : What consists of cooling water circuit and coal & ash circuit in steam power plant?
Last Answer : The cooling water circuit consists of a pump, condenser and cooling tower. The coal and ash circuit consists of coal delivery, preparation of coal, handling of coal to the boiler furnace, ash handling and ash storage.
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 : 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 : Amount of coal lost in ash particle, which is carried through the boiler system, depends upon the (A) Physical nature, ash content and fineness of the coal (B) Amount of excess air supplied and load on the boiler (C) Type of burner and combustion chamber (D) All (A), (B) and (C)
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 : 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 : 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 : Coal is heated in presence of air to a temperature of about __________ °C, while determining its ash content for proximate analysis. (A) 500 (B) 750 (C) 950 (D) 1100
Last Answer : (B) 750
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 : Which of the following constituents of coal is the most important in the production of coke? (A) Moisture (B) Ash (C) Volatiles (D) Carbon
Last Answer : (D) Carbon
Description : A good coking coal should have high __________ content. (A) Ash (B) Sulphur & phosphorus (C) Moisture (D) None of these
Description : Coal containing large quantity of __________ are difficult to wash. (A) Ash (B) Inherent mineral matter (C) Free impurities (D) Volatile matter
Last Answer : (B) Inherent mineral matter
Description : Mineral matter, 'M' and ash percentage 'A' in coal are roughly related as (A) M = 1.8 A (B) M = 0.5 A (C) M = 1.1 A (D) M = A
Last Answer : (C) M = 1.1 A
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 : 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)
Description : Mineral matter content (M) and ash content (A) in coal are approximately related as (A) M = 1.1A (B) M = A (C) M = 1.5A (D) M = 2A
Last Answer : (A) M = 1.1A
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 : 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 : 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 : For long flame and easy ignition, the coal used should have (A) High volatile matter (B) Low ash (C) High calorific value (D) High ash
Last Answer : (A) High volatile matter
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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 coal with high __________ content, would ignite most easily. (A) Fixed carbon (B) Volatile matter (C) Ash (D) Oxygen
Last Answer : (B) Volatile matter
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 : 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