Explosion limit of blast furnace gas is 37 to 71% gas in gas-air mixture. It means that the blast furnace gas will explode when burnt in a confined space, if its concentration in the gas-air mixture is __________ percent?
Quantity of coke produced from metallurgical coal may be around __________ percent?
The liquid used for the washing of coal in an industrial coal washery is a mixture of water and __________?
Which of the following constituents of coal is the most important in the production of coke ?
The combustion reaction, C + O2 = CO2, is __________?
Orsat apparatus is meant for __________?
Yield of coke oven gas in low temperature carbonisation of coal is about __________ Nm3 /ton of dry coal?
Blast furnace gas burns with a bluish flame, because of the presence of__________?
Calorific value of pitch creosote mixture (PCM) i.e., C.T.F.-200 is about__________?
Fuel gases containing hydrocarbons (e.g. coke oven gas) are not preheated before burning, mainly because __________?
Calorific values of both the solid as well as the liquid fuels can be determined by __________ calorimeter?
Calorific value of bituminous coal may be around __________ Kcal/kg?
Stack heat losses can be minimised by__________?
Method of maintaining fires in furnace during standby periods without undue consumption of fuel is called__________?
Anthracite coal __________?
By-products are __________ recovered in ‘Beehive ovens’ ?
A coal containing very high percentage of durain is called __________ coal?
The function of secondary combustion air is to __________?
Temperature of coke oven gas just before entering into saturator (for recovery of NH3) is about __________ °C?
Producer gas containing least amount of tar is produced by the__________?
Incomplete combustion of fuel in the furnace is judged by high __________ of the flue gases?
Which of the following is used for making the explosive „TNT‟ ?
Safe condition for storage of high V.M. bituminous coal is that __________?
Flue gas from the heating chamber of by product coke ovens is removed by__________?
Mineral matter, ‘M’ and ash percentage ‘A’ in coal are roughly related as__________?
Calorific value of dry wood may be around __________ Kcal/kg?
Combustion of pulverised coal as compared to that of lump coal __________?
During coal carbonisation process, the conversion of semi-coke to coke is accompanied by an increase in the __________ of the mass?
Coal tar fuel – 200 (CTF 200) is a mixture of __________?
Sometimes water is sprayed during coal charging in the coke oven, which helps in __________?
The sequence of absorption in flue gas analysis by Orsat’s apparatus is respectively__________?
Improper storage condition results in the weathering of coal and spontaneous combustion, which increases its__________?
Critical Air Blast (CAB) value of coke is a direct measure of its__________?
A particular coal is said to be free burning when it __________?
Ultimate analysis of coal determines its __________ content?
Higher efficiency in the combustion of solid fuel cannot be achieved by__________?
If oxygen content in the flue gas rises too high, fuel is being wasted by __________?
During combustion of a gaseous fuel, the presence of a non-luminous flame is an indication of the__________?
__________ process is meant for direct hydrogenation of coal to produce liquid fuel?
One kg of carbon for theoretically complete combustion requires __________ kg of air?
When incomplete combustion loss is high, the flue gas analysis shows large amount of __________?
Naphthalene recovered from coke oven gas is used__________?
Grindability index of a coal is 100. It implies that the __________?
In high temperature carbonisation (as compared to low temperature carbonisation) of coal, the__________?
Which of the following is not a manufactured fuel ?
Prime coking coal is always blended with medium or non- coking coal before carbonisation__________?
Low temperature carbonisation of coal takes place at __________ °C?
With increase in calorific value of fuels, their adiabatic flame temperatures__________?
Which of the following is not applicable to fluidised bed combustion of coal ?
Efficiency of the combustion of a fuel is judged by the __________ the flue gas?
Preheating of a gaseous fuel results in increased__________?

Fussain _____________________?

A. Is friable, charcoal like substance
B. Has highest fixed carbon and lowest volatile matter content of all the four banded components
of coal
C. Is non-coking, but when blended with highly coking coal, controls its swelling and produces
high strength coke on carbonisation
D. All A., B. and C.

Correct Answer: D. All A., B. and C. ✔

Last Updated: March 08, 2019