Portland cement is a fine powder gray or white in color, that consist of a mixture of hydraulic cement materials comprising primarily of calcium silicates, aluminates and alumino ferrites, more than 30 raw materials are known to be used in the manufacture of Portland cement and these materials can be divided into four distinct categories: calcareous, siliceous, argillaceous and ferriferous.
materials are chemically combined through by processing and subjected to
subsequent mechanical processing operation to form gray and white Portland
Portland cement has lower iron and manganese content than grey Portland cement
and it’s used primarily for decorative purposes
Portland cement manufacturing plants are part of of hydraulic cement manufacturing which also include natural, masonry and pozzolanic cement, the six digit source classification code (SCC) for Portland wet process wet process kilns is 3-05-006 and the six digit classification code for plants with dry process kiln is 3-05-007
The Manufacture Process of Portland cement
Cement is manufactured in two major ways
1. The wet process
2. The dry process
The two processes is essentially the same except
that in the wet process, the raw materials are grounded with water before being
fed into the kiln.
These materials are mined directly, dry materials are clean of any water after it is grounded and mixed thoroughly in the correct proportion.
The mixture is fed into the rotary kiln from the
upper end at a uniform rate heated to a temperature ranging from 1427 to 1530
degree Celsius, the rotary kiln is attached at an angle that makes it sloppy
such that materials fed into it from the upper end travels gradually to the
lower end of the cylindrical kiln, heating, heating is coal powered. Fuel oil
can also be used. When heated to the working temperature stated above, chemical
reaction is initiated between the ingredients of the mixture. The first
material formed is known as clinker, the clinker is ground with a controlled
amount of gypsum and the final product is known as Portland cement
Wet process differs from dry process in that water is introduced into the raw material but (calcium compound) it has the same process as dry cement production.