the discussion on the manufacturing process of cement that how actually a portland cement is manufactured in cement industry

1. CONCRETE TECHNOLOGY
 Name:Muhammad Junaid Shafi
 Sec:E
 Deptt:Civil Engg;
 Roll No:168

2. MANUFACTURING OF CEMENT
 Cement is the basic ingredient of constuction and
the most widely used constructing material.
 It is a very critical ingredient because only
cement has the capicity to enhance the viscosity
in concrete.
 This viscocity provides an interlocking platform
for all aggregates,water and admixtures.

3. CONT…
 Definition:
The six step process by
which Raw materials after a series of
physical and chemical changes
changes into a very fine powder like
binding material is called manuf: of
cement.

4. FLOW CHART

5. BEFORE DISCUSSING THE TOPIC….

6. CONT….
 There are manily two types of manufacturing
processes:
1)Dry process(25%)
2)Wet process(75%)
If we use water then it is Wet otherwise it will be
Dry process.

7. WET PROCESS

8. WET PROCESS(PREFERRED TO USE)
a)Easiest to controle chemistry and better for moist
raw materials.
b)Having high fuel requirements
c)Pre-heater further enhance the fuel efficiency so
increase the productions rates

9. SIX STEPS;;
1)Raw materials extraction/Quarry
2)Grinding,Proportioning and Blending
3)Pre-heater phase
4)Kiln phase
5)Cooling and Final Grinding
6)Packing and Shipping

10. 1ST STEP) RAW MATERIALS EXTRACTION
 Cement uses Raw materials that cover Ca,Si,Fe &
Al.
 Limestone for Ca,Sand & Clay fulfills the need of
Si.Fe & Al.
 Raw materials are extracted from the Quarry &
by means of Conveyor belt materials are
transported to the cement plant.
 There are also other Raw materials used in trace
amounts,For ex;

11. CONT….
 Shale(Si02,Al2O3,fe2O3)
 Fly Ash
 Mill scale
 Bauxite
 Before transportation to the plant,large size rocks
are crushed into smaller size rocks with the help
of crusher at Quarry.
 Crusher reduces large rocks to size of gravels.

12. QUARRIYNG

13. 2ND STEP) PROPRTIONING,BLENDING & GRINDING
 The Raw materials from Quarry are now routed
in plant where they are analyzed and proper
proportioning of limestone & clay.
 At this stage lime stone is 80% and Clay is 20%.

14. CONT….
 Now cement plant grind the raw mix with the
help of heavy rollers and rotating table.
 Rotating table rotates continously under the roller
and brought the raw mix with the roller.
 Roller crushes the materials to a fine powder &
finishes the Job.
 Raw mix then is stored in a Pre-Homogenizer.

15. CRUSHER

16. 3RD STEP) PRE-HEATING RAW MATERIALS
 After final grinding,the material is ready to face
the pre-heating chamber.
 Pre-heater chamber consists of series of vertical
cyclone from where the raw materials before
entering into the kiln.
 Pre heating chamber utilizes the emitting hot
gases from kiln.

17. CONT…

18. CONT….
 Pre heating of the materials saves Energy and
make plant environmental friendly.

19. 4TH STEP) KILN PHASE
 A rotary kiln is a huge rotating furnace having 7m
diameter and 230m length and is slightly inclined.
 It is the most important and critical phase of the
cement plant so it requires a proper controlling
process which is the following;
a)Critical parameters: Fuel,Feed
b)Temprature
c)Stability & Instrumentation

20. KILN PHASE…
a) Feeding of kiln:Delivery of a proper proportions
of the Raw mix into the kiln alongwith water is
called feeding of thr kiln.
This raw mixture is fed ar the
upper end of the kiln.
b)Fuels: Kiln is heating up from the lower end or
exit side by the use of natural gas and pulverized
coal.
The amount of coal used for manufacturing of

21. KILN PHASE…
Of 1 tonn(2200 lb) cement is 100kg-350kg
depreding upon the process used.
The fuels can be any combustible hydrocarbons.
TEMPRATURE: the temprature of the kiln is
1450*C-1500*C.

22. KILN CONT…

23. 5TH STEP) CLINKER FORMATION,COOLING & CEMENT
MAKING PROCESS
 Climker Formation:The Raw materials mixture
moves down in kiln & due to high tempratures
various ch; changes occurs.
a)Any water present is driven off
b)Decarbonation of calcium carbonate.
c)In the hottest(lower end) part of the kiln,some 20
to 30% materials become liquid & lime,silica &
alumina recombine.

24. CLINKER….
d) The mass fuses into balls 3-25mm in diameter is
called clinker and the associated temprature is
called clinkering temprature.

25. CLINKER COMPOSITION;
 A typical clinker has the following composition:
CaO2=65%
SiO2=20%
AL2O3=10%
Fe2O3=5%

26. CLINKER…
Cooling of the clinker::
After passing out from the
kiln,clinkers are cooled by means of force air due to
temprature exchange with that air.
Clinker released the absorbed heat cool down o
lower temprature.
>>>>Released heat is reused by recirculating it
back to the kiln saves ENERGY.

27. CLINKER COOLER

28. CLINKER…
Final Grinding(Rotating Ball Mill)::
Final process of 5th phase is the final
grinding.There is horixental filled with steel
balls.Clinker reach in this rotating drum after
cooling.Here,steel balls tumble and crush the
clinker to very fine powder.
>>>During Grinding GYPSUM is also added t the
mix in small % that controles the setting of cement.

29. FINAL GRINDING…
 Rotating Ball Mill

30. PACKAGING AND SHIPPING
 The cement is then housed in storage silos,from
where it is hydrualically extracted and transported
to facilities where it will be packaged in sacks or
supplied in bulk.
 In either caseit can be shipped by rail car,truck or
ship.

31. VISCOUS PASTE RAEDY TO USE..