Question

1. briefly introduce the production process of cement
2. what are four kinds of mineral composition of portland cement

Explanation:

1. The production process of cement generally involves raw - material preparation (mixing limestone, clay etc.), crushing and grinding, calcination in a kiln to form clinker, and finally grinding the clinker with gypsum to make cement.
2. The four main mineral compositions of Portland cement are tricalcium silicate ($C_3S$), dicalcium silicate ($C_2S$), tricalcium aluminate ($C_3A$), and tetracalcium alumino - ferrite ($C_4AF$).

Answer:

1. Raw - material preparation, crushing and grinding, calcination, and final grinding.
2. Tricalcium silicate, dicalcium silicate, tricalcium aluminate, tetracalcium alumino - ferrite.