Sometimes water is sprayed during coal charging in the coke oven,
which helps in
(A) Prevention of clinker formation in the oven
(B) Controlling the dust nuisance while charging the coal
(C) Reducing the cracking of hydrocarbons in the gas and increasing the
percentage of CO & H2
in the gas (due to the endothermic reaction represented
by C + H2O = CO + H2
)
(D) All (A), (B) and (C)

1 Answer

Answer :

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

Related questions

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)

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

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 : The gasification reaction represented by, C + H2O = CO + H2 , is (A) Exothermic (B) Endothermic (C) Catalytic (D) Autocatalytic

Last Answer : (B) Endothermic

Description : The gasification reaction represented by, C + H2O = CO + H2 , is a/an __________ reaction. (A) Exothermic (B) Endothermic (C) Catalytic (D) Autocatalytic

Last Answer : (B) Endothermic

Description : When steam is passed over coal resulting in the endothermic reaction represent by, C + H2O = CO + H2 , it is called the __________ of coal. (A) Carbonisation (B) Oxidation (C) Coalification (D) Gasification

Last Answer : (D) Gasification

Description : Which of the following is the most reactive (as regards the formation of CO + H2 from C + H2O)? (A) Blast furnace coke (B) Low temperature coke (C) Anthracite coal (D) Sub-bituminous coa

Last Answer : (B) Low temperature coke

Description : Which of the following is an endothermic reaction? (A) Absorption of SO3 in 98% H2SO4 (B) C + H2O = CO + H2 (C) Thermal dissociation of iron pyrites (D) Both (B) and (C)

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

Description : Which of the following is the costliest source of hydrogen needed for ammonia manufacture under Indian condition? (A) Electrolysis of water (B) Cryogenic removal of H2 from coke oven gas (C) Steam reforming of naphtha (D) Natural gas cracking

Last Answer : (A) Electrolysis of water

Description : Which of the following is the costliest method for commercial production of hydrogen for ammonia synthesis? (A) H2 separation from coke oven ga (B) Steam reforming of naphtha (C) Cracking of natural gas (D) Electrolysis of water

Last Answer : (D) Electrolysis of water

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 : Forward reaction will be favoured for the exothermic reaction, represented by CO + H2O ⇌ CO2 + H2, by (A) Low temperature and high pressure (B) Low temperature and low pressure (C) High temperature and high pressure (D) High temperature and low pressure

Last Answer : (A) Low temperature and high pressure

Description : CO & H2 are the constituents of (A) Producer gas (B) Water gas (C) Coke oven gas (D) All (A), (B) and (C)

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

Description : Which of the following reactions occuring during coal gasification is called the Neumann reversal reaction? (A) 2CO ↔ C + CO2 (B) CO + H2O ↔ CO2 + H2 (C) C + H2O ↔ CO + H2 (D) C + 2H2O ↔ CO2 + 2H2

Last Answer : (A) 2CO ↔ C + CO2

Description : Coke oven gas consists mainly of (A) H2 & CH4 (B) CO & CO2 (C) H2 & CO (D) CH4 & CO

Last Answer : (A) H2 & CH4

Description : Coke oven gas constitutes mainly of (A) H2 & CO (B) H2 & CH4 (C) CH4 & CO (D) H2 & CO2

Last Answer : (B) H2 & CH4

Description : Coke oven gas consists mainly of (A) H2 , & CH4 (B) CO, & CO2 (C) H2 , & CO (D) CH4 , & CO

Last Answer : (A) H2 , & CH4

Description : With increase in the time of carbonisation at a particular temperature(say 1000°C), the __________ percentage in coke oven gas increases. (A) Hydrogen (B) Methane (C) Unsaturated hydrocarbons (D) All (A), (B) and (C)

Last Answer : (A) Hydrogen

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 : Largest constituent of coke oven gas is (A) N2 (B) H2 (C) CH4 (D) CO

Last Answer : (B) H2

Description : The shift conversion reaction taking place during water gas manufacture is given by (A) C + H2O ↔ CO + H2 (B) C + 2H2O ↔ CO2 + 2H2 (C) CO + H2O ↔ CO2 + H2 (D) None of these

Last Answer : (C) CO + H2O ↔ CO2 + H2

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 : 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 : 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 : For the manufacture of concrete a low density, the aggregate used is (a) Furnace clinker (b) Coke breeze (c)Saw dust (d) All the above

Last Answer : (d) All the above

Description : During the carbonisation of coal (A) All tar is evolved at < 600°C (B) Evolution of H2 and formation of methane and aromatics occur at > 700°C (C) Hard semi-coke starts shrinking at 600°C (D) All (A), (B) and (C)

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

Description : Steam is intermittently admitted into the fuel bed during the production of producer gas to (A) Convert CO to CO2 (B) Increase the combustion rate (C) Increase the gas production rate (D) Minimise the chances of clinker formation

Last Answer : (D) Minimise the chances of clinker formation

Description : Pick out the endothermic reaction out of the following. (A) C+ ½O2 = CO (B) CO + 3H2 = CH4 + H2O (C) CaCO3 = CaO + CO2 (D) CO + ½O2 = CO2

Last Answer : (C) CaCO3 = CaO + CO2

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 : Pick out the wrong statement: (A) Carburetted water gas is also called blue gas (B) Coals are divided in four species according to their carbon content in Seylor's classification (C) Carbonisation time ... and net calorific value of a fuel is the same, if it does not contain hydrogen or hydrocarbons

Last Answer : (A) Carburetted water gas is also called blue gas

Description : Though increased pressure has a retarding effect on cracking reaction, yet in actual process, a positive pressure of 10-15 kgf/cm2 is maintained during cracking mainly to (A) Increase the yield of ... coke formation (C) Enhance the octane number of gasoline (D) Reduce gum content in gasoline

Last Answer : (B) Suppress coke formation

Description : Commercial production of hydrogen for the manufacture of nitrogenous fertilisers is done by (A) Steam reforming of naphtha and cracking of natural gas (B) Electrolysis of water (C) Cryogenic separation of hydrogen from coke oven gas (D) All (A), (B) and (C)

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

Description : Use of catalyst is a must in the ammonia manufacture, because the reaction is reversible as well as the heat of dissociation of N2 & H2 is high. The presence of promoter along with the catalyst helps in ... B) Increasing the effectiveness (C) Improving the strength & heat resistance (D) All a, b & c

Last Answer : (D) All a, b & c

Description : Pick out the wrong statement (A) Co-current absorbers are usually used, when the gas to be dissolved in the liquid is a pure substance (B) In case of gas absorption, HETP is ... reaction (D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process

Last Answer : (D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process

Description : Given, 3H2 + CO = CH4 + H2O, KP = 10 1.84 and, 4H2 + CO2 = CH4 + 2H2O, KP = 10 1.17 the KP for the reaction CO + H2O = CO2 + H2 is (A) 10 3.01 (B) 10 -0.67 (C) 10 -3.01 (D) 10 0.67

Last Answer : (D) 10 0.67

Description : Pick out the exothermic reaction out of the following: (A) C + H2O = CO + H2 (B) CaC2 + H2O = Ca(OH)2 + C2H2 (C) MgCO3 = MgO + CO2 (D) All (A), (B) and (C)

Last Answer : (B) CaC2 + H2O = Ca(OH)2 + C2H2

Description : Coke oven gas burns with a yellowish flame, because of the presence of (A) CO2 (B) CH4 (C) H2 (D) NH3

Last Answer : (B) CH4

Description : Bog iron used for the adsorption of H2S from coke oven gas is (A) An intimate mixture of saw dust and iron dust (i.e. moist ferric hydroxide) (B) Iron impregnated with resin (usually Bakelite) (C) Carbon free iron (D) None of these

Last Answer : (A) An intimate mixture of saw dust and iron dust (i.e. moist ferric hydroxide)

Description : 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) ... chamber (B) Risk of explosion (C) Chances of clinker formation (D) Incomplete combustion of coal

Last Answer : (B) Risk of explosion

Description : When volume of the equilibrium reaction C(s) + H2O(g) ⇌ CO(g) + H2(g) is increased at constant temperature the equilibrium will :

Last Answer : When volume of the equilibrium reaction C(s) + H2O(g) ⇌ CO(g) + H2(g) is increased at constant ... left c. be unaltered d. can not be predicted

Description : A coal having higher volatile matter content, has lower (A) Smoking tendency on burning (B) Coke oven gas yield on carbonisation (C) Chance of catching fire during storage in open space (D) Ignition temperature

Last Answer : (D) Ignition temperature

Description : Water gas is the combination of – (1) CO and H2 (2) CO2 and H2 (3) CO and H2O (4) CO2 and CO

Last Answer : (1) CO and H2 Explanation: Water has is a synthesis gas, containing carbon monoxide (CO) and hydrogen has (H2). It is made by passing steam over a redhot carbon fuel such as coke. The reaction between steam and hydrocarbons produce the has mixture.

Description : Which of the following is not a commercially used feed-stock for the production of ammonia synthesis gas? (A) Water (B) Naphtha (C) Tar (D) Coal/coke oven gas

Last Answer : (C) Tar

Description : Which of the following is the costliest source of getting hydrogen on commercial scale for the manufacture of nitrogenous fertiliser? (A) Coal gasification (B) Steam reforming of naphtha (C) Electrolysis of water (D) Coke oven gas

Last Answer : (C) Electrolysis of water

Description : Name the endothermic reaction out of the following: (A) Catalytic cracking (B) Hydrocracking (C) Dehydrogeneration of Naphthene to produce aromatic (D) Catalytic polymerisation

Last Answer : (C) Dehydrogeneration of Naphthene to produce aromatic

Description : Cracking is (A) An exothermic reaction (B) An endothermic reaction (C) Favoured at very low temperature (D) None of these

Last Answer : (B) An endothermic reaction

Description : In the fluid catalytic cracker (FCC), the cracking reaction is __________ (i) and the regeneration is__________ (ii) __________. (A) (i) exothermic (ii) endothermic (B) (i) exothermic (ii) exothermic (C) (i) endothermic (ii) endothermic (D) (i) endothermic (ii) exothermic

Last Answer : (D) (i) endothermic (ii) exothermic

Description : Fuel used in B.F. stove is (A) Pulverised coal (B) Furnace oil (C) Blast furnace gas/mixed gas (D) Coke oven gas

Last Answer : (C) Blast furnace gas/mixed gas

Description : The main product of high temperature carbonisation of coal is (A) Coke (B) Ammonia (C) Tar (D) Coke oven gas

Last Answer : (A) Coke

Description : Yield of coke oven gas in low temperature carbonisation of coal is about __________ Nm3 /ton of dry coal. (A) 60 (B) 160 (C) 500 (D) 750

Last Answer : (B) 160