Question

To obtain cement dry powder, lime stones and shales or their slurry, is burnt in a rotary kiln at a temperature between ___

(a) 1100° and 1200°C

(b) 1200° and 1300°C

(c) 1300° and 1400°C

(d) 1400° and 1500°C

The question was posed to me during an interview.

This interesting question is from Dry Process topic in section Cement of Concrete Technology

Answer 1

The correct answer is (d) 1400° and 1500°C

The explanation is: In this process calcareous material such as lime stone (calcium carbonate) and argillaceous material such as clay are ground separately to fine powder in the absence of water and then are mixed together in the desired proportions.