Basic Composition of Portland Cement

Cement is made of calcareous and argillaceous rock materials, obtained from quarries. Thus from the chemical viewpoint, the main components are carbonates and silicates. The raw materials used for cement are given in Tables 10-1 and 10-2. The active components in cement formulations are listed in Table 10-3. 

There are two processes for manufacturing cements, the dry process and the wet process. The dry process is cheaper than the wet process, but in practice 

Limestone CaCOs, sedimentary rock formed by the accumulation of shells or corals 

Cement rock Sedimentary rock with composition similar to industrial cement 

Marl Loose deposit consisting mainly of CaCOs 

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