The maximum percentage of CO2 in a flue gas (from a carbonaceous fuel) can be(A) 21(B) 77(C) 79(D) 29

The maximum percentage of CO2
in a flue gas (from a carbonaceous
fuel) can be
(A) 21
(B) 77
(C) 79
(D) 29
by

1 Answer

Answer :

(A) 21
by

Related questions

A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2 . It means that (A) 21% excess air has been used for combustion (B) 21% excess oxygen has been used for combustion (C) Complete combustion of fuel has taken place (D) No excess air has been used for combustion

Description : A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2 . It means that (A) 21% excess air has been used for combustion (B) 21% excess oxygen has ... (C) Complete combustion of fuel has taken place (D) No excess air has been used for combustion

Last Answer : (C) Complete combustion of fuel has taken place

In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of (A) Use of non-preheated combustion air (B) Use of pulverised solid fuels (C) Imperfect mixing of fuel & air and infiltration of air (D) Use of excessive positive draft in the furnace

Description : In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of (A) Use of non-preheated combustion air (B) Use of pulverised solid ... of fuel & air and infiltration of air (D) Use of excessive positive draft in the furnace

Last Answer : (C) Imperfect mixing of fuel & air and infiltration of air

Volumetric composition of flue gas analysed with the Orsat apparatus is : CO2 = 12%, O2 = 8%, CO = nil, N2 = 80%. This flue gas composition indicates that (A) Pure oxygen has been used for combustion (B) Nitrogen percentage in the fuel is very high (C) Excess air has been used for combustion (D) Hydrogen is not present in the fuel

Description : Volumetric composition of flue gas analysed with the Orsat apparatus is : CO2 = 12%, O2 = 8%, CO = nil, N2 = 80%. This flue gas composition indicates that (A) Pure oxygen has been used for combustion ... very high (C) Excess air has been used for combustion (D) Hydrogen is not present in the fuel

Last Answer : (C) Excess air has been used for combustion

On volume basis, air contains following parts of oxygen  (a) 21  (b) 23  (c) 25  (d) 77  (e) 79.

Description : On volume basis, air contains following parts of oxygen  (a) 21  (b) 23  (c) 25  (d) 77  (e) 79.

Last Answer : Answer : a

Efficiency of the combustion of a fuel is judged by the __________ the flue gas. (A) % of CO2 in (B) % of O2 in (C) Temperature of (D) Colour of

Description : Efficiency of the combustion of a fuel is judged by the __________ the flue gas. (A) % of CO2 in (B) % of O2 in (C) Temperature of (D) Colour of

Last Answer : (B) % of O2 in

Flue gas obtained on complete combustion of pure acetylene (a hydrocarbon fuel) will contain (A) CO (B) CO2 (C) H2O (D) Both (B) & (C)

Description : Flue gas obtained on complete combustion of pure acetylene (a hydrocarbon fuel) will contain (A) CO (B) CO2 (C) H2O (D) Both (B) & (C)

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

Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it. Presence of bacteria helps in (A) Coagulation and flocculation of colloids (B) Oxidation of carbonaceous matter to CO2 (C) Nitrification or oxidation of ammonia derived from breakdown of nitrogenous organic matter to the nitrite and eventually to the nitrate (D) All (A), (B) and (C)

Description : Bacterial aerobic oxidation of polluted water in biological oxidation ponds is done to purify it. Presence of bacteria helps in (A) Coagulation and flocculation of colloids (B) Oxidation of carbonaceous matter to CO2 (C) ... to the nitrite and eventually to the nitrate (D) All (A), (B) and (C)

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

15 17 21 29 45 77 ? a) 109 b) 125 c) 141 d) 173 e) None of these

Description : 15 17 21 29 45 77 ? a) 109 b) 125 c) 141 d) 173 e) None of these

Last Answer : 15 + 2 = 17 17 + 4 = 21 21 + 8 = 29 29 + 16 = 45 45 + 32 = 77 77 + 64 = 141 Answer: c)

Oxygen percentage in the flue gas coming out of a gaseous fuel fired furnace should be ideally about __________ percent. (A) < 2 (B) < 5 (C) < 8 (D) < 10

Description : Oxygen percentage in the flue gas coming out of a gaseous fuel fired furnace should be ideally about __________ percent. (A) < 2 (B) < 5 (C) < 8 (D) < 10

Last Answer : (A) < 2

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 volatile matter percentage in coal is called its 'fuel ratio' (D) Calorific value of natural gas is more than that of LPG

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

Too much of excess air in combustion results in high (A) Fuel consumption for the same heat load (B) Stack gas temperature (C) Percentage of oxygen in flue gases (D) All (A), (B) and (C)

Description : Too much of excess air in combustion results in high (A) Fuel consumption for the same heat load (B) Stack gas temperature (C) Percentage of oxygen in flue gases (D) All (A), (B) and (C)

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

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

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

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

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

In order to maintain an oxidising atmosphere in a furnace, it should have (A) More of excess air (B) Less of excess air (C) More of CO in flue gas (D) More of CO2 in flue gas

Description : In order to maintain an oxidising atmosphere in a furnace, it should have (A) More of excess air (B) Less of excess air (C) More of CO in flue gas (D) More of CO2 in flue gas

Last Answer : (A) More of excess air

Scaling of furnace stock is reduced by __________ in flue gas. (A) CO (B) H2 (C) High CO/CO2 (D) All (A), (B) & (C)

Description : Scaling of furnace stock is reduced by __________ in flue gas. (A) CO (B) H2 (C) High CO/CO2 (D) All (A), (B) & (C)

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

The sequence of absorption in flue gas analysis by Orsat's apparatus is respectively (A) CO2 , O2 , CO (B) CO, O2 , CO2 (C) CO2 , CO, O2

Description : The sequence of absorption in flue gas analysis by Orsat's apparatus is respectively (A) CO2 , O2 , CO (B) CO, O2 , CO2 (C) CO2 , CO, O2

Last Answer : (A) CO2 , O2 , CO

When incomplete combustion loss is high, the flue gas analysis shows large amount of (A) CO2 (B) CO (C) O2 (D) C

Description : When incomplete combustion loss is high, the flue gas analysis shows large amount of (A) CO2 (B) CO (C) O2 (D) C

Last Answer : (B) CO

The average molecular weight of a flue gas having the composition by volume as CO2 = 25%, O2 = 25%, N2 = 50% will be (A) 27.6 (B) 23 (C) 47.3 (D) 42.9

Description : The average molecular weight of a flue gas having the composition by volume as CO2 = 25%, O2 = 25%, N2 = 50% will be (A) 27.6 (B) 23 (C) 47.3 (D) 42.9

Last Answer : (B) 23

Oxygen percentage (by weight) in atmospheric air is (A) 19 (B) 21 (C) 23 (D) 29

Description : Oxygen percentage (by weight) in atmospheric air is (A) 19 (B) 21 (C) 23 (D) 29

Last Answer : (C) 23

The respective storm totals at three surrounding stations A, B and C are 110, 90 and 70 mm. If the normal annual precipitation amounts at stations X, A, B and C are respectively 1000, 1100, 1200 and 1250 mm, the estimated storm precipitation at X is (A) 75 mm (B) 77 mm (C) 79 mm

Description : The respective storm totals at three surrounding stations A, B and C are 110, 90 and 70 mm. If the normal annual precipitation amounts at stations X, A, B and C are respectively 1000, 1100, 1200 and 1250 mm, the estimated storm precipitation at X is (A) 75 mm (B) 77 mm (C) 79 mm

Last Answer : Answer: Option B

Which of the following accounts for maximum energy loss in a boiler? (A) Flue gases (B) Ash content in the fuel (C) Incomplete combustion (D) Unburnt carbon in flue gases

Description : Which of the following accounts for maximum energy loss in a boiler? (A) Flue gases (B) Ash content in the fuel (C) Incomplete combustion (D) Unburnt carbon in flue gases

Last Answer : (A) Flue gases

To maximize the combustion efficiency, which of the following in the flue gas needs to be done? a) maximize O2 b) maximize CO2 c) minimize CO2 d) maximize CO

Description : To maximize the combustion efficiency, which of the following in the flue gas needs to be done? a) maximize O2 b) maximize CO2 c) minimize CO2 d) maximize CO

Last Answer : b) maximize CO2

Acid dew point temperature (ADT) of a flue gas produced by the combustion of a fuel containing 1% sulphur may be about __________ °C. (A) 80 (B) 130 (C) 180 (D) 250

Description : Acid dew point temperature (ADT) of a flue gas produced by the combustion of a fuel containing 1% sulphur may be about __________ °C. (A) 80 (B) 130 (C) 180 (D) 250

Last Answer : (B) 130

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

Description : 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

Last Answer : (B) Flame temperature

Higher efficiency in the combustion of solid fuel cannot be achieved by (A) Proper fuel preparation (B) Keeping the flue gas exhaust temperature very high (C) Adopting efficient-fuel firing technique & equipment (D) Supplying correct quantity of combustion air

Description : Higher efficiency in the combustion of solid fuel cannot be achieved by (A) Proper fuel preparation (B) Keeping the flue gas exhaust temperature very high (C) Adopting efficient-fuel firing technique & equipment (D) Supplying correct quantity of combustion air

Last Answer : (B) Keeping the flue gas exhaust temperature very high

If oxygen content in the flue gas rises too high, fuel is being wasted by (A) Incomplete combustion (B) Dry gas/stack gas loss (C) Moisture loss (D) None of these

Description : If oxygen content in the flue gas rises too high, fuel is being wasted by (A) Incomplete combustion (B) Dry gas/stack gas loss (C) Moisture loss (D) None of these

Last Answer : (B) Dry gas/stack gas loss

During combustion of a gaseous fuel, the presence of a non-luminous flame is an indication of the (A) Incomplete combustion (B) Complete combustion (C) High oxygen in flue gas (D) None of these

Description : During combustion of a gaseous fuel, the presence of a non-luminous flame is an indication of the (A) Incomplete combustion (B) Complete combustion (C) High oxygen in flue gas (D) None of these

Last Answer : (B) Complete combustion

Preheating of a gaseous fuel results in increased (A) Flame length (B) Flame temperature (C) Quantity of flue gas

Description : Preheating of a gaseous fuel results in increased (A) Flame length (B) Flame temperature (C) Quantity of flue gas

Last Answer : (B) Flame temperature

A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the (A) Presence of large quantity of hydrogen in the fuel (B) Low calorific value of the fuel (C) High sulphur content in the fuel (D) Lack of thorough mixing of fuel with air

Description : A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the (A) Presence of large ... fuel (C) High sulphur content in the fuel (D) Lack of thorough mixing of fuel with air

Last Answer : (D) Lack of thorough mixing of fuel with air

Pitch creosote mixture (PCM) as compared to furnace oil is a better fuel, because its (A) Emissivity factor is higher (B) Sulphur content is lower (C) Flue gas has lower dew point thereby facilitating more waste heat recovery (D) All (A), (B) and (C)

Description : Pitch creosote mixture (PCM) as compared to furnace oil is a better fuel, because its (A) Emissivity factor is higher (B) Sulphur content is lower (C) Flue gas has lower dew point thereby facilitating more waste heat recovery (D) All (A), (B) and (C)

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

Incomplete combustion of a fuel is characterised by the high __________ in the flue gas. (A) Smoke (B) Temperature (C) Oxygen (D) Carbon monoxide

Description : Incomplete combustion of a fuel is characterised by the high __________ in the flue gas. (A) Smoke (B) Temperature (C) Oxygen (D) Carbon monoxide

Last Answer : (D) Carbon monoxide

The main drawback of supplying more excess air in the combustion of fuel is the (A) Excessive power requirement of air blower (B) Enhanced sensible heat loss in the flue gas (C) Intermittent and uncontrolled combustion of the fuel (D) High exit flue gas temperature from the furnace

Description : The main drawback of supplying more excess air in the combustion of fuel is the (A) Excessive power requirement of air blower (B) Enhanced sensible heat loss in the flue gas (C) Intermittent and uncontrolled combustion of the fuel (D) High exit flue gas temperature from the furnace

Last Answer : (B) Enhanced sensible heat loss in the flue gas

White flue gas (resembling steam) coming out of the chimney of a thermal power plant indicates that the fuel used in the boiler furnace is (A) Tar (B) Coke oven gas (C) Pitch (D) Pulverised coke

Description : White flue gas (resembling steam) coming out of the chimney of a thermal power plant indicates that the fuel used in the boiler furnace is (A) Tar (B) Coke oven gas (C) Pitch (D) Pulverised coke

Last Answer : (B) Coke oven gas

A national random sample of 20 ACT scores from 2010 is listed below. Calculate the sample mean and standard deviation. 29, 26, 13, 23, 23, 25, 17, 22, 17, 19, 12, 26, 30, 30, 18, 14, 12, 26, 17, 18 a. 20.50, 5.79 b. 20.50, 5.94 c. 20.85, 5.79 d. 20.85, 5.94

Description : A national random sample of 20 ACT scores from 2010 is listed below. Calculate the sample mean and standard deviation. 29, 26, 13, 23, 23, 25, 17, 22, 17, 19, 12, 26, 30, 30, 18, 14, 12, 26, 17, 18 a. 20.50, 5.79 b. 20.50, 5.94 c. 20.85, 5.79 d. 20.85, 5.94

Last Answer : Katie earned 84,92,84,75 and 70 on her first 5 tests. What is the minimum grade Katie needs to earn on the next test to have a mean of 84?

What is the theoretical limit of the efficiency of a single-crystal single-junction cell in a photovoltaic system? w) 9 percent x) 29 percent y) 79 percent z) 99 percent

Description : What is the theoretical limit of the efficiency of a single-crystal single-junction cell in a photovoltaic system? w) 9 percent x) 29 percent y) 79 percent z) 99 percent

Last Answer : ANSWER: X -- 29 PERCENT

As the C/H ratio of the fuel increases, the amount of CO2 formed on combustion __________ for the same percentage of excess air. (A) Decreases (B) Increases (C) Remain same (D) May increase or decrease depending on the type of fuel

Description : As the C/H ratio of the fuel increases, the amount of CO2 formed on combustion __________ for the same percentage of excess air. (A) Decreases (B) Increases (C) Remain same (D) May increase or decrease depending on the type of fuel

Last Answer : (B) Increases

Volumetric ratio of N2 to O2 in dry atmospheric air is (A) 0.21 (B) 3.76 (C) 4.76 (D) 0.79

Description : Volumetric ratio of N2 to O2 in dry atmospheric air is (A) 0.21 (B) 3.76 (C) 4.76 (D) 0.79

Last Answer : (B) 3.76

measures oxygen and temperature of the flue gas. a) Fuel efficiency monitor. b) Combustion analyzer. c) Contact thermometer. d) Infrared thermometer.

Description : measures oxygen and temperature of the flue gas. a) Fuel efficiency monitor. b) Combustion analyzer. c) Contact thermometer. d) Infrared thermometer.

Last Answer : Combustion analyzer

Economizer is provided to utilize the flue gas heat for ___ a) preheating the boiler feed water b) preheating the stock c) preheating the combustion air d) preheating fuel

Description : Economizer is provided to utilize the flue gas heat for ___ a) preheating the boiler feed water b) preheating the stock c) preheating the combustion air d) preheating fuel

Last Answer : preheating the boiler feed water

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

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

Oxygen trim control strategy __ a. continuously measures the oxygen content in the flue gas b. adjusts the combustion air flow c. Continually tuning the air-fuel mixture. d. All of above

Description : Oxygen trim control strategy __ a. continuously measures the oxygen content in the flue gas b. adjusts the combustion air flow c. Continually tuning the air-fuel mixture. d. All of above

Last Answer : d. All of above

Which of these is an output of a ‘Furnace’? a. Fuel gas b. Cool Air c. Flue gases d. Water Vapor

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

The economiser is used in boilers to........ A]Increase thermal efficiency of boiler B]Economise on fuel C]Extract heat from the exhaust the gases D]Increase flue gas temperature

Description : The economiser is used in boilers to........ A]Increase thermal efficiency of boiler B]Economise on fuel C]Extract heat from the exhaust the gases D]Increase flue gas temperature

Last Answer : A]Increase thermal efficiency of boiler

Which among the following has the highest flue gas loss on combustion due to Hydrogen in the fuel? a) natural gas b) furnace oil c) coal d) light diesel oil

Description : Which among the following has the highest flue gas loss on combustion due to Hydrogen in the fuel? a) natural gas b) furnace oil c) coal d) light diesel oil

Last Answer : a) natural gas

What city in 29 N and 77 E?

Description : What city in 29 N and 77 E?

Last Answer : Need answer

In a Examination a candidate has to score minimum of 24 marks inorder to clear the exam. The maximum that he can score is 40 marks. Identify the Valid Equivalance values if the student clears the exam. A. 22,23,26 B. 21,39,40 C. 29,30,31 D. 0,15,22

Description : In a Examination a candidate has to score minimum of 24 marks inorder to clear the exam. The maximum that he can score is 40 marks. Identify the Valid Equivalance values if the student clears the exam. A. 22,23,26 B. 21,39,40 C. 29,30,31 D. 0,15,22

Last Answer : C. 29,30,31

Asphalts are(A) Low molecular weight & low boiling point compounds present in petroleum (B) Desirable in catalytic cracking feedstock, because they produce coke (C) Readily oxidisable and form carbonaceous sludge (D) All (A), (B) & (C)

Description : Asphalts are (A) Low molecular weight & low boiling point compounds present in petroleum (B) Desirable in catalytic cracking feedstock, because they produce coke (C) Readily oxidisable and form carbonaceous sludge (D) All (A), (B) & (C)

Last Answer : (C) Readily oxidisable and form carbonaceous sludge

Carbonaceous particles having size less than 1 μm are called (A) Grit (B) Aggregates (C) Aerosols (D) Smoke

Description : Carbonaceous particles having size less than 1 μm are called (A) Grit (B) Aggregates (C) Aerosols (D) Smoke

Last Answer : (D) Smoke

Presence of carbonaceous matter in the sewage (A) Causes reduction in its dissolved oxygen content thereby endangering the life of aquatic creatures (B) Reduces sulphate ions to sulphides causing obnoxious smell (C) Increases the quantity of chlorine used for its purification (D) All (A), (B) and (C)

Description : Presence of carbonaceous matter in the sewage (A) Causes reduction in its dissolved oxygen content thereby endangering the life of aquatic creatures (B) Reduces sulphate ions to sulphides causing obnoxious ... quantity of chlorine used for its purification (D) All (A), (B) and (C)

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

A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Description : A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Last Answer : (B) 11.77 kPa