A. Porosity
B. Coke reactivity index (CRI)
C. Critical air blast (CAB) value
D. Both B. and C.
Related Mcqs:
- Narrow coke ovens as compared to wider coke ovens_________________?
A. Produce smaller coke
B. Produce stronger coke
C. Require less time of carbonisation
D. All A., B. and C. - Width of the coke oven towards coke side is slightly more than that on pusher side to____________________?
A. Facilitate easy discharging of coke as it swells during carbonisation
B. Facilitate uniform heating of the oven
C. Increase the output of the coke
D. None of these - Coke made in narrower by-product coke ovens (as compared to wider ovens) is _____________________?
A. Less reactive
B. Stronger
C. Smaller in size
D. All A., B. & C. - Degree of carbonisation of coal during coke making can be roughly judged by the ______________ of the coke produced?
A. Colour
B. Moisture content
C. Ash content
D. Volatile matter - During coal carbonisation process, the conversion of semi-coke to coke is accompanied by an increase in the _______________ of the mass?
A. Density
B. Porosity
C. Electrical resistivity
D. None of these - 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 coal - Percentage of hydrogen in coke oven gas may be around ___________________?
A. 10
B. 25
C. 45
D. 60 - Removal of hydrogen from coke oven gas ___________________?
A. Increases its calorific value
B. Decreases its calorific value
C. Does not alter its calorific value
D. Is not possible on commercial scale - The ratio of % total carbon obtained in the ultimate analysis of coke and % fixed carbon obtained in the proximate analysis is always ___________________?
A. 1
B. < 1
C. > 1
D. Unpredictable - Higher percentage of ash in coal meant for the production of metallurgical grade coke ___________________?
A. Decreases the hardness of coke
B. Decreases the abrasion resistance of coke
C. Causes brittleness in steel
D. None of these
