Lower part of hot metal mixer are lined with _____________ bricks?

Lessing ring is formed by the addition of a partition across the centre of a raschig ring, which results in an area increase of about ______________ percent?

A. 5

B. 20

C. 35

D. 55

In chemical process equipments, the conical bottom heads used, usually has an apex angle of____________________?

A. 20°

B. 40°

C. 60°

D. 80°

Si percentage in silica refractories used in the walls of coke oven is about______________________?

A. 45

B. 60

C. 80

D. 95

Chrome magnesite bricks are_________________?

A. Acidic in nature

B. Neutral in nature

C. Having higher RUL than silica bricks

D. Made by mixing 30% Chromite and 70% Periclase

Maximum shrinkage in volume occurring during burning/firing of dried refractories may be as high as ______________ percent?

A. 10

B. 15

C. 20

D. 30