This slide explains step by step process of manufacturing of portland cement

1. Manufacturing of portland
cement

2. CEMENT:-
• A powdery substance made
by calcining lime and clay,
mixed with water to form
mortar or mixed with sand,
gravel, and water to make
concrete.
• The raw materials required
for manufacture of portland
cement are calcareous
materials ,such as lime
stone and chalk and
argillaceous material ,such
as shale or clay

3. PROCESS OF MANUFACTURING OF CEMENT
• The process of
manufacturing of cement
consists of grinding the raw
materials , mixing them
intimately in certain propor-
tions depending upon their
purity and composition and
burning them in a kiln at a
temperature of about 1300
to 1500 C , at which
temperature clinkers are
formed and they are made
into fine powder in addition
with 3 to 5% of gypsum to
form port lad cement.

4. Types of processes
Flow chart
• There are two process
known as “wet” and “dry”
processes depending upon
whether the mixing and
grinding of raw materials
is done in wet or dry
conditions .For many years
wet process remained
popular because of the
possibility of more accurate
in the mixing of raw
materials. Later, the dry
process gained momentum
with modern development
of technique’s

5. Wet process
• Wet process : In this process, the
raw materials are changed to
powdered form in the presence of
water . In this process, raw
materials are pulverized by using a
Ball mill, which is a rotary steel
cylinder with hardened steel balls.
When the mill rotates, steel balls
pulverize the raw materials which
form slurry(liquid mixture). The
slurry is then passed into storage
tanks, where correct proportioning
is done . Proper composition of
raw materials can be ensured by
using wet process than dry
process. Corrected slurry is then
fed into rotary kiln for burning.

6. Wet Process: Continued------
• This process is generally used when raw materials are
soft because complete mixing is not possible unless
water is added . Actually the purpose of both
processes is to change the raw materials to fine
powder.

7. Dry process
• Dry process : In this
process calcareous
material such as
limestone (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.

8. Dry process continued _ _ _
• Water is then added to it for getting thick paste and
then its cakes are formed, dried and burnt in kilns.
This process is usually used when raw materials are
very strong and hard . In this process, the raw
materials are changed to powdered form in the
absence of water.

9. THE END
PPT BY YERUVA NARENDRA BABU