Spontaneous combustion of coal on storage results due to(A) Inadequate ventilation (B) Low temperature oxidation (C) Storage in large heaps with small surface to volume ratio (D) All (A), (B) and (C)

Spontaneous combustion of coal on storage results due to
(A) Inadequate ventilation
(B) Low temperature oxidation
(C) Storage in large heaps with small surface to volume ratio
(D) All (A), (B) and (C)
by

1 Answer

Answer :

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

Related questions

To avoid fire by spontaneous combustion of coal due to its low temperature oxidation, it should be stored in (A) Shallow and small piles (B) Fine sizes without the presence of any lump (C) Closed space without any ventilation facility (D) Large heaps with small surface to volume ratio

Description : To avoid fire by spontaneous combustion of coal due to its low temperature oxidation, it should be stored in (A) Shallow and small piles (B) Fine sizes without the presence of any lump (C) Closed space without any ventilation facility (D) Large heaps with small surface to volume ratio

Last Answer : (A) Shallow and small piles

Rate of low temperature oxidation of coal due to bad storage conditions (A) Decreases with increase in surface area (B) Does not vary with increase in surface area (C) Is more for low volatile coal compared to high volatile coal (D) Is accelerated by storage in large heaps with small surface to volume ratio

Description : Rate of low temperature oxidation of coal due to bad storage conditions (A) Decreases with increase in surface area (B) Does not vary with increase in surface area (C) Is more for low volatile ... to high volatile coal (D) Is accelerated by storage in large heaps with small surface to volume ratio

Last Answer : (D) Is accelerated by storage in large heaps with small surface to volume ratio

Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if (A) It contains large amount of volatile matter (B) It is stored in tall heaps (C) Smaller fines are stored in large quantity (D) All (A), (B) and (C)

Description : Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if (A) It contains large amount of volatile matter (B) It is stored in tall heaps (C) Smaller fines are stored in large quantity (D) All (A), (B) and (C)

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

Low temperature oxidation of coal is accelerated by the (A) Storage in large heaps (B) Storage in compressed piles (C) Absence of porous or friable particles (D) All (A), (B) and (C)

Description : Low temperature oxidation of coal is accelerated by the (A) Storage in large heaps (B) Storage in compressed piles (C) Absence of porous or friable particles (D) All (A), (B) and (C)

Last Answer : (A) Storage in large heaps

A coal having high ratio of volatile matter to fixed carbon as compared to a coal having low ratio of volatile matter to fixed carbon (A) Is less liable to spontaneous combustion on storage (B) Is more difficult to ignite and produces a shorter flame (C) Requires smaller combustion space and less secondary air (D) None of these

Description : A coal having high ratio of volatile matter to fixed carbon as compared to a coal having low ratio of volatile matter to fixed carbon (A) Is less liable to spontaneous combustion on storage (B) ... a shorter flame (C) Requires smaller combustion space and less secondary air (D) None of these

Last Answer : (D) None of these

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

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

Violent gassing from a lead-acid battery while it is being charged, indicates that the _____________. A. plate separators are grounded B. battery compartment ventilation is inadequate C. electrolyte specific gravity is too low D. charging rate is too high

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The bright glow of a combustion process is the characteristic of __________ temperature oxidation of coal. (A) Fast & high (B) Slow & low (C) Slow & high (D) Fast & slow

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Temperature of preheated air used for the transportation of pulverised coal through pipes to the burner of a boiler furnace is restricted to a maximum limit of about 300° C to avoid the (A) Requirement of large volume combustion chamber (B) Risk of explosion (C) Chances of clinker formation (D) Incomplete combustion of coal

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Last Answer : (B) Risk of explosion

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)

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)

Low temperature oxidation of coal during storage does not decrease its (A) Oxygen content (B) Caking power (C) Calorific value (D) None of these

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Last Answer : (D) None of these

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

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_________ is a substance which undergoes spontaneous combustion. a) wood b)coal c)sodium d)cow dung cakes

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Combustion of fuel in a furnace with oxygen enriched air results in higher (A) Flue gas volume (B) Flame temperature (C) Fuel consumption (D) Stack loss

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Last Answer : (A) It cannot burn low grade coal

Which of the following are NOT key constraints of the food processing industry? a) Inadequate quality control. c) High packaging cost b) Low demand. d) Poor infrastructure as in no cold storage

Description : Which of the following are NOT key constraints of the food processing industry? a) Inadequate quality control. c) High packaging cost b) Low demand. d) Poor infrastructure as in no cold storage

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Combustion of pulverised coal as compared to that of lump coal (A) Develops a non-luminous flame (B) Develops a low temperature flame (C) Can be done with less excess air (D) Provides a lower rate of heat release

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When Marrion divided 24 oranges into 3 heaps in the ratio 4 to 5 to 3 how many oranges were in each heap?

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When the nurse notes that the post cardiac surgery patient demonstrates low urine output (< 25 ml/hr) with high specific gravity (> 1.025), the nurse suspects: a) Inadequate fluid volume Urine output of less than 25 ml/hr may indicate a decrease in cardiac output. A high specific gravity indicates increased concentration of solutes in the urine which occurs with inadequate fluid volume. b) Normal glomerular filtration Indices of normal glomerular filtration are output of 25 ml or greater per hour and specific gravity between 1.010 and 1.025. c) Overhydration Overhydration is manifested by high urine output with low specific gravity. d) Anuria The anuric patient does not produce urine.

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Spontaneous Human Combustion: myth or reality?

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Do you think spontaneous combustion can actually happen?

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