Heat transfer rate to the stock/charge in the furnace does not depend upon the(A) Emissivity of the refractory walls(B) Size of the furnace(C) Use of waste heat recovery equipments(D) Thickness of the stock

Heat transfer rate to the stock/charge in the furnace does not depend
upon the
(A) Emissivity of the refractory walls
(B) Size of the furnace
(C) Use of waste heat recovery equipments
(D) Thickness of the stock
by

1 Answer

Answer :

(C) Use of waste heat recovery equipments
by

Related questions

Heat transfer rate to the charge/stock in a furnace does not depend upon the (A) Type of fuels viz. solid, liquid or gaseous (B) Flue gas temperature (C) Emissivity of refractory walls (D) Initial temperature of the charged stock

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Last Answer : (A) Type of fuels viz. solid, liquid or gaseous

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)

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

In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on the (A) Rate of firing and emissivity of flame (B) Thermal conductivity of the charge & structural materials of furnace (C) Nature of process; whether batch, continuous or intermittent (D) All (A), (B) and (C)

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Thermal efficiency of furnaces can be improved by (A) Waste heat recovery from flue gas (B) Minimising heat losses from furnace walls(C) Maintaining proper draught(D) All (A), (B) and (C

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The heating capacity of continuous reheating furnace depends upon the (A) Hearth area and furnace temperature (B) Emissivity of the stock (C) Ratio of wall surface to stock surface (D) All (A), (B) and (C)

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Tar is a better fuel than furnace oil, because of its (A) Higher calorific value (B) Lower sulphur content (C) Higher emissivity (0.8-0.9) resulting in higher radiation heat transfer rate (D) Both (A) and (B)

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Design of waste heat boiler for recovery of waste heat from furnace gases depends upon the(A) Quantity & temperature of waste gas(B) Dust concentration & nature of dust in waste gas(C) Corrosive nature of the waste gas(D) All (A), (B) and (C)

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A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre. (A) 0.01 (B) 0.1 (C) 0.25 (D) 0.5

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reduction in thermal resistance during heat transfer does not occur in the (A) Convection heat transfer by stirring the fluid and cleaning the heating surface (B) Conduction heat transfer by reduction in the material thickness and increase in the thermal conductivity (C) Radiation heat transfer by increasing the temperature and reducing the emissivity (D) None of these

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Test specimen for determination of refractoriness under load (RUL) of a refractory is heated in a (A) Furnace employing neutral atmosphere (B) Carbon resistance furnace (C) Reducing atmosphere (D) Furnace employing negative pressure

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Refractory bricks having high thermal conductivity is desirable, when it is to be used in the (A) L.D. converter (B) Blast furnace (C) Rotary kiln (D) Recuperator

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One face of a furnace wall is at 1030°C and the other face is exposed to room temperature (30°C). If the thermal conductivity of furnace wall is 3 W. m-1. k-1 and the wall thickness is 0.3 m, the maximum heat loss (in W/m) is (A) 100 (B) 900 (C) 9000 (D) 10000

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Oxygen enrichment of combustion air does not result in increase of the (A) Flame temperature (B) Oxygen in the flue gas (C) Stack loss (D) Heat transfer rate in the furnace

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