internship report(zia ul hassan,13-me-01)

INTERNSHIP REPORT

ZIA UL HASSAN (13-ME-01) Mechanical Engg. Department UET Taxila

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INTERNSHIP REPORT

KHAIRPUR PLANT, KALAR KAHAR, CHAKWAL.

SUBMITTED BY:

Zia Ul Hassan

13-ME-01

MECHANICAL ENGINEERING DEPARTMENT,

UET TAXILA

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CONTENTS

PREFACE....................................................................................................................................4

ACKNOWLEDGEMENT.............................................................................................................5

1. ABSTRACT .........................................................................................................................5

2. INTRODUCTION.................................................................................................................7

2.1 D.G. KHAN CEMENT COMPANY ....................................................................................7

2.2 POWER GENERATION .....................................................................................................7

2.3 ENVIRONMENTAL MANAGEMENT ...............................................................................8

2.4 NISHAT GROUP................................................................................................................8

2.5 MIAN MOHAMMAD MANSHA ........................................................................................9

2.6 HISTORY OF CEMENT .....................................................................................................9

2.7 EXPLANATION ................................................................................................................9

2.8 CEMENT PRODUCTION................................................................................................. 10

3. BLOCK DIAGRAM ........................................................................................................... 11

4. POWER PLANT ................................................................................................................. 12

5. STEPS OF PRODUCTION.................................................................................................. 15

5.1 QUARRY ................................................................................................................... 15

5.2 LIMESTONE CRUSHER ............................................................................................ 16

5.3 STORAGE YARD....................................................................................................... 17

5.4 STACKER .................................................................................................................. 18

5.5 SIDE SCRAPPER ....................................................................................................... 19

5.6 RECLAIMER.............................................................................................................. 19

5.7 RAW MILL FEED AREA ........................................................................................... 19

5.8 ELECTROSTATIC PRECIPITATOR........................................................................... 21

5.9 RAW MILL ................................................................................................................ 22

5.10 COAL STORAGE AREA ............................................................................................ 23

5.11 COAL MILL ............................................................................................................... 24

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5.12 CF SILO .......................................................................................................24

5.13 CYCLONE PRE HEATERS ........................................................................................ 26

5.14 GAS ANALYZER ....................................................................................................... 26

5.15 ROTARY KILN .......................................................................................................... 26

5.16 CLINKER SILO .......................................................................................................... 28

5.17 CEMENT MILL FEED AREA ..................................................................................... 29

5.18 CEMENT MILL .......................................................................................................... 30

5.19 CEMENT SILO........................................................................................................... 30

5.20 PACKING PLANT ...................................................................................................... 31

6. CENTRAL CONTROL ROOM (CCR)................................................................................. 32

7. LABORATORIES .............................................................................................................. 33

8. PLC.................................................................................................................................... 33

9. WASTE HEAT RECOVERY PLANT.................................................................................. 33

10. SAFETY MEASURES .................................................................................................... 34

11. FUTURE TRENDS OF PLANT ....................................................................................... 35

12. CONCLUSION ............................................................................................................... 35

13. REFERENCES................................................................................................................ 36

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PREFACE

The purpose of the report is to elaborate on my experience about DGKCC (Pvt)

Limited. I have tried to present the overview of the company and its operations and the

task that are carried out during my stay at DGKCC (Pvt) Limited. Although 6 weeks is

a small time to completely understand the processes and philosophy of a company, but

at least one gets a good overview about it, and I have tried to write all that grasped

during this short time, in this report. This report includes DGKCC working way outs,

information about their departments function and working.

Learning in practical side is somewhat that cannot be compared with books knowledge.

BSc Mechanical Engineering program is designed in such a way that students are

required to do the projects and researches then give their recommendation and

conclusion. It also provides student an opportunity to apply this knowledge in practical

field.

Now to fulfil the practical requirement of this course, I successfully completed an

internship report on DGKCC (Pvt) Limited, a unit of Nishat Group. It was great

opportunity for me to apply the theoretical knowledge and get practical exposure. I

have visited almost all the departments and studied function of each department at

factory.

I have analysed their working and have given certain recommendations on the basis of

my observation. I have tried my level best to give real look about DGKCC while writing

this report. May ALLAH succeed me while evaluation of this report.

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ACKNOWLEDGEMENT

My greatest thanks to Allah Almighty. Allah who bestowed me with the ability and

potential to complete this Internship. Before I go into thick of the things, I would like

to add a few deepest words for the people who were part of this report in numerous

ways… people who gave unending support right from the stage the report was

assigned. Particularly I also wish to thank the managerial staff at DG Cement who

helped me to gain a lot of information regarding the company and cement industry

and also who provide me an opportunity to learn and understand the working of

organization as an internee. I am also thankful to Mr. Yar Muhammad (Manager) and

Mr. Ali (Trainee Engineer) who played a role of polar star for me in the organization

and whose experience taught me a lot about the industry and the organization.

And finally deepest and warmest appreciation to the whole team of DG Khan Cement

Company.

1. ABSTRACT

Dera Ghazi Khan Cement Company Limited Khair Pur Plant a unit of NISHAT group

is a strategic business unit of Nishat Group, which is the largest and most growing

industrial group in Pakistan. D.G. Khan Cement Co. is market leader with respect to

market share with about 11.4%. Apart from its competitors, its product is relative ly

high priced yet it has highest market share because of good quality. That is the reason

why it is producing most of the cement needed in the country as compared to other

cement companies. Its plant is situated in Dera Ghazi Khan and Khair Pur and head

office is situated at Lahore. All the plants are situated in places where the raw materials

needed are all at one place.

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Among these plants, two are located in DG Khan while one in Khair pur near

Kallar Kahar. This one is installed with the collaboration of a Danish company called

FLS. Much of its machinery is imported from Germany clearly showing that it has

high-tech machines running and gives it a clear upper edge on the competitors. This

plant has a total production capacity of 6700 TPD.

Currently the company is also exporting the cement to various countries like Iraq, India,

Afghanistan and UAE. D.G Khan Cement has also contract with ELEPHANT cement

at Sri Lanka.

To the big machinery running here, the power needed to keep it running is also massive.

Total power being provided to this plant is 32.3 MW to energize this massive

mechanical setup.

The fuel consumption is also a matter of concern and new ways to reduce or minimize

the fuel consumption is under the attention. The proof of this is the newly created RDF

plant where various pollutants scattered all around are brought and baked to produce

heat that is sent to the kiln along with the conventional fuel being used. This is also a

significant and intelligent way of reducing the pollution from the environment.

In addition to this, there is also a paper mill running here for the purpose of producing

plastic bags to be supplied to the packing plant. A total of 1.6 million bags are being

produced for this purpose. They not only suffice the packing requirements in the plant

itself but are also sold to the neighbour contemporaries.

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2. INTRODUCTION

2.1 D.G. KHAN CEMENT COMPANY

D.G. Khan Cement Company Limited (DGKCC), a unit of Nishat group, is the second

largest cement-manufacturing unit in Pakistan with a production capacity of 13,400

tons clinker per day. It has a countrywide distribution network and its products are

preferred on projects of national repute both locally and internationally due to the un-

parallel and consistent quality. It is list on all the Stock Exchanges of Pakistan.

DGKCC was established under the management control of State Cement Corporation

of Pakistan Limited (SCCP) in 1978. DGKCC started its commercial production in

April 1986 with 2000 tons per day (TPD) clinker based on dry process technology.

Plant & Machinery was supplied by UBE Industries of Japan.

Expansion Khairpur Project.

The Group has also set up a new cement production line of 6,700 TPD clinker near

Kalar Kahar, Distt, Chakwal, the single largest production line in the country. First of

its kind in cement industry of Pakistan, the new plant has two strings of pre-heater

towers, the advantage of twin strings lies in the operational flexibility whereby

production may be adjusted according to market conditions. The project equipped with

two vertical cement grinding mills. The cement grinding mills are first vertical Mills in

Pakistan. The new plant is not only increasing the capacity but also providing

proximity to the untapped market of Northern Punjab and NWFP besides making it

more convenient to export to Afghanistan from northern borders.

2.2 POWER GENERATION

For continuous and smooth operations of the plant uninterrupted power supply is very

crucial. The company has its own power generation plant along with WAPDA supply.

The installed generation capacity is 23.84 MW.

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2.3 ENVIRONMENTAL MANAGEMENT

DG Khan Cement Co. Ltd., production processes are environment friendly and comply

with the World Bank’s environmental standards. It has been certified for “Environment

Management System” ISO 14001 by Quality Assurance Services, Australia. The

company was also certified for ISO-9002 (Quality Management System) in 1998. By

achieving this landmark, DG Khan Cement became the first and only cement factory

in Pakistan certified for both ISO 9002 & ISO 14001.

2.4 NISHAT GROUP

NISHAT GROUP is one of the most renowned business groups in Pakistan. It was

founded by Mian Muhammad Mansha in 1951. It is playing a significant role in the

private sector by adding value to cotton and the cotton based economy. Nishat Group

ranks among the top five business houses in Pakistan terms of sales and assets. The

company has fixed/current assets of over Rs.300 billion (US$ 5 billion), it ranks

amongst the top five business houses of Pakistan and has a strong presence in textiles,

cement and financial services, as well as a market share in insurance, power generation,

paper products and aviation.

Nishat Mills Limited started out as a weaving unit with 500 semi-automatic looms,

later on 10,000 spindles were added, laying the foundation of nation’s biggest textile

composite project. Today, Nishat Mills Limited is largest vertically integrated unit of

Pakistan. It comprises of 270,000 spindles, 740 state of the art shuttles- less and air jet

looms, a processing capacity of three million meters and stitching capacity of more

than one million meters per month, supported by a power generation plant with a

capacity of 33.6 MW.

D.G. Khan Cement Company Limited (DGKCC), a unit of Nishat group, is the largest

cement-manufacturing unit in Pakistan with a production capacity of 5,500 tons clinker

per day. It has a countrywide distribution network and its products are preferred on

projects of national repute both locally and internationally due to the un-parallel and

consistent quality. As discussed earlier, the premium quality of the cement produced

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by this very company is due to the state of the art machinery imported from

abroad. It is listed on all the Stock Exchanges of Pakistan. Furthermore, DG Khan

cement company`s plant near Kallar Kahar production line of 6,700 TPD clinker, the

single largest production line in the country.

2.5 MIAN MOHAMMAD MANSHA

MIAN MOHAMMAD MANSHA, the chairman of Nishat Group continues the spirit

of entrepreneurship and has led the Group successfully to make it the premier business

group of the region. The group has become a multidimensional corporation and has

played an important role in the industrial development of the country. In recognition of

his un parallel contribution, the Government of Pakistan has also conferred him with

“Sitara-e-Imtiaz”, one of the most prestigious civil awards of the country.

2.6 HISTORY OF CEMENT

England first made Portland cement early in the 19th century by burning powdered

limestone and clay in his kitchen stove. By this crude method he laid the foundation for

an industry which annually processes literally mountains of limestone, clay, cement

rock, and other materials into a powder so fine it will pass through a sieve capable of

holding water. Cement is so fine that one pound of cement contains 150 billion grains.

Portland cement, the basic ingredient of concrete, is a closely controlled chemica l

combination of calcium, silicon, aluminum, iron and small amounts of other ingredients

to which gypsum is added in the final grinding process to regulate the setting time of

the concrete. Lime and silica make up about 85% of the mass. Common among the

materials

2.7 EXPLANATION

1. The cement manufacturing process begins when limestone, the basic raw

material used to make cement, is transported by dumper trucks to the crusher plant fro m

the limestone quarry 3-4 kilometers away.

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2. The limestone is combined with clay, ground in a crusher and fed into

the additive silos. Sand, iron and bottom ash are then combined with the limestone and

clay in a carefully controlled mixture which is ground into a fine powder in a roller

mill.

3. Then, the fine powder is heated as it passes through the Pre-Heater Tower into

a large kiln, which has length of 66 meters and diameter 5.5 meters. In the kiln, the

powder is heated to 1500 degrees Celsius. This creates a new product, called clinker,

which resembles pellets about the size of marbles.

4. The clinker is combined with small amounts of gypsum and limestone and

finely ground in a finishing mill (cement mill).

5. The cement manufacturing process consists of many simultaneous and

continuous operations using some of the largest moving machinery in manufactur ing.

A number of sensors and computers allow the entire operation to be controlled by a

single operator from a Central Control Room (CCR).

2.8 CEMENT PRODUCTION

RAW MATERIALS

1. Lime stone

2. Clay

3. Iron ore, Bauxite & Silica

4. Gypsum

1. LIME STONE

This raw material is owned by company and is extracted from nearby quarry unit.

Limestone has the highest composition in the cement production.

2. CLAY

Clay is another nature resource used in cement production.

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3. IRON ORE, BAUXITE & SILICA

Iron ore is not extracted from quarry unit but it is bought from contractors. This

is added in very small quantity to strengthen the cement.

4. GYPSUM

Gypsum is retarding agent and is used to increase setting time (to slow down hardening

process).

BAG FILTER

The dust produced by crushing process can cause damage to the equipment and may

produce dust, to overcome this problem a bag filter is employed. A fan blows air and

all the dust goes to the bag filter. Inside the bag filter a special type of canvas cloth is

used. When air passes through this filter cloth, the dust particles stick to the cloth and

clean air passes through. The dust particles are then collected and sent to the conveyor.

After sometime when the filter is choked with particles, purging system is used in

which high pressure air is used, this air removes all particles from the filter cloth.

3. BLOCK DIAGRAM

The block diagram shown below is useful for the reader to take a glance at. This will

greatly increase the level of ease to learn all the process easily. Each block below shows

the steps:

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4. POWER PLANT

DG Khan Cement has decided to set up its second 8.6-megawatt waste heat recovery

power plant, this time at its Khairpur site at a cost of Rs2.5 billion. The first plant started

trial operation in May last year. The right shares issued by the company are expected

to help raise capital for the new plant, say analysts. Electricity produced from the plant

will help replace the expensive electricity purchased from the Water and Power

Development Authority, the company said in a statement on Thursday. The project,

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expected to be completed in fiscal 2013, will result in an annual savings of

Rs300 to Rs350 million. The company is also considering procuring foreign loan worth

Rs1.5 billion ($16.5 million) while equity portion will be bought through issuance of

right shares.

For continuous and smooth operations of the plant uninterrupted power supply is very

crucial. The power is supplied to the huge machinery with the help of;

a) Two grids from WAPDA of 132kW power.

b) Two transformers in the power station producing 632 kW power.

The company has its own power generation plant along with WAPDA supply. The

power provided by WAPDA is converted to 632 kW by the step down transformer.

The Company power plant consists of two Generators, these are dual nature generators

that can be run on GAS as well as on Diesel depends upon availability of fuel. In case

if any of supporting engine fails to work the company has Turbine Engine of

CATERPILLARS so that there is no load shedding at all. The two generators

combine produce 32.2MV of energy one generator produce 16.1MV and other one

also of 16.1MV. Maintenance of generators is made by staff of WARTSILLA.

These transformers are then connected to all the panels in the sub-stations. This

connection is based on the bus topology that is a common bus of wires is running from

where more wires branch out and supply power to panels of the required ratings. There

are total of thirteen panels of thirteen substations.

Details of the transformers deployed to power up the machinery are:

PEL IEC-76

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PARAMETER QUANTITY

Type of coupling ONAN

KVA 1600

Frequency 50 Hz

Volts (HV) 6300

Volts (LV) 415

Amperes (HV) 146.63

Amperes (LV) 2275.93

Phases (HV) 3

Phases (LV) 3

Impedance volts 8%

PARAMETER QUANTITY

Oil Liters 1489

Weight of oil 1312 KG

Total weight 4612 KG

Year of manufacture 2005

Switch position 1 6615 H.T Volts

Switch position 2 6457.5 H.T Volts





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MOTORS:

Motors of the following power are being used mainly;

LOCATION POWER

Limestone Crusher 1540 kW

Cement mill 3400 kW

Raw mill suction fan 5100 kW

Raw mill main motor 3400 kW

Cooling fan motors 237 kW

ID fans 1800 kW

5. STEPS OF PRODUCTION

5.1 QUARRY

Quarry is the place from where raw material in extracted. The technique used to extract

the raw material is by drilling first and then blasting. A hole of about 10-

15 m is drilled and ammonium nitrate in filled as an explosive in these

holes. When this explosive is ignited the rocks are broken into pieces of

different sizes. These pieces are then loaded on the dumper trucks of Caterpillar

Company and using conveyor belt to the crusher. It is located about 3-4 Km from the

plant. The raw material used is:

I. Clay as it contains silicon in abundance.

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II. Silicon is the main material used in the production of cement. It is to

be used along with limestone to produce cement. There is 25% contribution of

silicon in cement. They are dumped into large dumps after extraction from the

rocks.

2. Limestone: The major contribution in the cement is of limestone.

It constitutes 95% of the total. It is cruicial to provide strenght. This

limestone is extracted by nearby Quarry and has the highes t

composition in cement.

3. Additives: The additives maily contain Bauxite, Nitirte, iron and Gypsum

(5%). They can be considered as accessories and they are meant for additional

quality of cement as well as being the catalysts.

5.2 LIMESTONE CRUSHER

The limestone crusher, supplied by FL Smidth has capacity of 1500 tons/hour.

Limestone is dumped into hopper firstly. Inside the crusher machine hammers having

an average weight of 101 kg crushes the big indigenous stones.

In crusher, the Squirral Cage Induction motors are used to rotate the hammers and

rotatry speed of motors is 1200 to 1300 rpm. The motor responcible for grinding is of

1540 Kw. Terminal box vibration monitor regulates and limites the vibration of huge

motors.

The crushed material is sent to suction bags where dust is sucked and re-used while the

other crushed material is conveyed by conveyor belts to the storage yard. To deal with

the magnetic particles, iron separator is used which is a magnet and thus separates out

the ferric material out there.

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5.3 STORAGE YARD

The function of storage yard is to store the crushed material is stored in the form of

piles in the storage yard. There are 6 piles in the storage yard. Characteristics of all

piles in storage yard are given as follows;

2 Mixed piles of limestone & clay

2 High grade pure limestone

Iron ore additive

Bauxite additive

Besides, there are four hoppers, each containing the material listed above respectively.

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5.4 STACKER

A stacker makes conical piles of the crushed material. Feed from storage yard is

conveyed to the stacker through conveyor belts. This stacker then moves to and fro to

make a pile.

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5.5 SIDE SCRAPPER

Side scrapper is a device which picks the crushed feed from the piles through its feed

belt called “Hoist”. This belt has a number of small buckets of low capacity. When

this belt moves, the buckets picks feed from the pile and put it on the belt conveyor.

Side scrapper in used for those piles which are required in low quantity like bauxite

and iron ore.

5.6 RECLAIMER

Reclaimer is an equipment which is used to throw feed dowm from the pile. It has

two ams called “Harrows” These harrows are inserted into the pile, when they move

sideward, the feed drops down the pile. This feed in then collected by high capacity

buckets installed in the bottom of the reclaimer. These buckets pick the feed and put it

on the the belt conveyor. It is a large capacity equipment and for those piles which are

required in high quantity like Mixed Pile

5.7 RAW MILL FEED AREA

The raw mill feed area has of 4 feed hoppers:

Mixed feed hopper

Pure limestone hopper

Bauxite hopper

Iron ore hopper

The capacity of first two hoppers is 800 tons while the other two hoppers have a

capacity of 600 tons. The feed from each pile is conveyed to the hoppers through

conveyor belts in relevant hoppers. Each hopper has 4 load cells. The feed is controlled

by load cells that sense the quantity of feed being loaded into hoppers. Separation of

iron pieces is also assured.

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The raw mill have total capacity of 500 tons/hour and the motors that are

used in raw mill are induction motors and have power of 4.3 kW supplier of motors

are FL Smidth. There are three sections of raw mill that are described as follows;

I. Table with three rollers:

The raw feed from the belt conveyor falls on the rotating table of the raw mill. The

table contains three crushing rollers. The raw fed is crushed to fine powder with these

rollers. Relatively bigger particles are collected at the bottom of raw mill and are

recycled for re-crushing.

II. Bottom scrapper:

At the top of the raw mill, there is separator section. A suction fan with motor power

of 4500 kW produces suction and sends dusty air into the cyclones at the top. Here the

dusty air rotates around a fixed axis causing particles to get separated from the air.

These particles are collected at the bottom of the cyclone and sent to the CF silo with

the help of air slides.

III. Separator:

In the next stage, hot gases from the kiln come from the bottom of the raw mill

and lift very fine particles with it. A suction fan with motor power of 4500 kW

produces suction and sends dusty air into the cyclones at the top. To separate the

air from the dust, air rotates and particles are separated from the air. These

particles are collected at the bottom of the cyclone and sent to the CF silo with

the help of air slides.

The air still contains some dust and to ensure that maximum amount of

dust has been received, conditioning tower is the place where this air is sent to

sprinkle water on it and in this way, dust (cement) gets separated.

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5.8 ELECTROSTATIC PRECIPITATOR

Electrostatic precipitator :

The clean air from the conditioning tower still contains some particles which have to

be removed. These particles are separated from air by passing it through the

Electrostatic precipitator.

In Electrostatic precipitator there are 2 corona wires which are mesh like. These wires

are negatively charged. There is a positively charged electrode in the centre which is

equidistant from both corona wires. Dusty air passes through these corona wires and

the particles get negatively charged. The negatively charged particles in air are then

attracted by the positively charged electrode and the particles stick with it and clean air

is exhausted from the chimney.

Cleaning of the electrostatic precipitator:

In order to remove particles from the electrode . A “Wrapping” device is used. This

device hits the electrode as a hammer and particles fall down from it. These particles

are collected and conveyod to the CF silo via screw conveyor.

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5.9 RAW MILL

Capacity: 500 tons/hr

Motor power : 4300 kw

Supplier : FLSmidth

Sections of Raw Mill:

There are 3 sections of a raw mill.

Table with 3 rollers

Bottom scrapper

Separator

Table:

The raw feed from the belt conveyor directly falls

on the rotating table of the raw mill. The table

contains 3 crushing rollers. The raw fed is

crushed to fine powder with these rollers. The

coarse particles are collected at the bottom of raw

mill and are sent to to the vibrator from where

they are sent to to the raw feed belt conveyor and

again recycled to the ram mill for re-crushing.

The vibrator is use to handle the quantity of the material being put on the belt.

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Separator:

At the top of the raw mill, there is separator section.

Hot gases from the kiln comes from the bottom of the

raw mill and lift very fine particles with it. A suction

fan with motor power of 4500 kw produces suction

and sends dusty air into the cyclones at the top. Here

the dusty air rotates and particles are separated from

the air. These particles are collected at the bottom of

the cyclone and sent to the CF silo with the help of

air slides. The air which still contains dust particles

are separated in Conditioning tower and Electrostatic precipitator.

Bottom separator:

Some fine particles from raw feed fall on the table, these particles are collected by

means of a bottom scrapper and sent to the CF silo.

5.10 COAL STORAGE AREA

Coal yard is the area where coal is stored which is used as fuel in baking the powered

raw materials to produce cement clinker. There are different piles for the storage of

local and imported coal. Coal is thrown on a sieved net by handler to separate bigger

pieces of coal and stones form it, before it goes to the tunnel. From the tunnels the coal

is placed on the belt conveyor which takes it to the coal mill feed area.

Then comes the stage of coal mill feed area. After the impurities are removed from the

coal, it is chatted on the belt conveyor. A bag filter is employed which sucks the coal

dust and thus prevents the coal from being wasted. The coal is then shifted to the coal

storage hoppers. Magnetic separated caters for the iron pieces in coal.

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There are three hoppers for storing coal each with the capacity of 250 tons.

Coal mill: now is the stage of coal mill. Coal mill at DG Khan cement has capacity of

52 tons/hour in case of mixed coal and 26 tons/hour in case of pet coal.

The total capacity of motors used in coal mill are 600kW.

Process in the coal mill is nearly the same as in raw mill.

5.11 COAL MILL

Specifications of coal mill :

Capacity: 52 ton/hr (coal mix)

26 ton/hr (pet coke)

Supplier: FLSmidth

Motor: 600 KW

Sections of a coal mill :

There are 3 sections of a coal mill similar to the raw mill.

(1) Table

(2) Rollers

(3) Bottom scrappers

The coal on the belt conveyor falls on the table of the mill where rollers grind it to a

fine powder. A blower of very high power pushes very fine particles towards the two

fine storage bins. From the 1st storage bin the coal is sent to the kiln for its use in the

burner and from 2nd storage bin it is sent to to the pre-calciner for calcinations.

5.12 CF SILO

Coming back to the raw mill where we have powered raw material, it is sent to the CF

or continuous flow silo with the help of bucket elevator. The CF silo is of;

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Capacity = 25,500 tons

Length = 54 meters

Diameter = 22.4 meters

The next stage would be pre heater. Low bin in the CF silo takes the material to

the air slides. Before that, air is circulated in silo in such a way to throw the material to

low big which can hold maximum of 118 tons.

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5.13 CYCLONE PRE HEATERS

There are total 10 cyclone pre heaters. Five are on the right side of the pre calciner and

5 on the left of the pre calciner. Purpose is to heat the material before sending it to kiln

for final baking.

Firstly, the material is sent on the top of second cyclone. The hot gases from

the kiln flow with very high speed and lift the particles to the top of the 1sr cyclone.

Then the material falls on the top of the 3rd cyclone and sends it into the 2nd

cyclone. Then the material falls on the top of 4th cyclone and hot gases take it into the

3rd cyclone. Then the material falls on the top of the 5th cyclone and hot gases take it

into the 4th cyclone and finally into the 5th cyclone pre heater.

5.14 GAS ANALYZER

In gas analyser, which is actually part of pre heaters, there are basically three cylind ers

which have CO2,O2 and S02 respectively in each cylinder. Three analyser machines

are used manufactured by ABB are used. Main purpose of this gas analyser is to clean

the gases before sending them to the kiln for burning process and for cleaning the gases

we send NH2 nitrogen into cylinders one by one to obtain zero numeric value for each

gas so that gas is free from dust etc and safe to send to kiln. Three analyser machines

are used manufactured by ABB are used.

5.15 ROTARY KILN

It is the most important part of cement maufacturing process as materials are baked

here to produce cement.

The kiln has length of 66 meters, diameter of 5.5 meters. its rotatry speed depends

upon the. In case of relatively larger feed, kiln will rotate faster and similarly its slow

rotation would indicate less quantity of feed. Inner part of kiln has refractory type and

provides insulation to outer environment with the help lining of bricks inside it. Outside

material also protects the envoirment. Arround the kiln, there are induced draft fans

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that sense temperature and if temperature rises from a limit the fans will turns

on automatically to ensure security to outer environment, otherwise, they will remain

off.

There are two motors, one on each side of the kiln. These motors have reasonably high

torque to accomplish the purpose of rotating this massive shaft. It moves with the

speed of 2.5 rpm usually.

The very hot material from kiln falls into kiln hood which has an angular sieve,when

material passes through the kiln hood it becomes clinker and now this clinker will be

sent to the clinker cooler.

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5.16 CLINKER SILO

Clinker silo is 60 m high and its width is 46 m. There are 3 gates at the bottom of the

clinker storage from where the clinker is the clinker from the deep pan conveyor is

stored in the clinker storage. Its capacity is 110,000 tons. Its length is sent to cement

mill through belt conveyor. Besides the main clinker storage bin, there is a temporary

clinker storage hopper with a capacity of 1400 tons. If the temporary hopper is also full

then the clinker is removed from the hopper and dumped into clinker storage yard.

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5.17 CEMENT MILL FEED AREA

There are two cement mills at the plant and there are total six hoppers in cement mills,

three in each mill in feed area.

The 1st hopper contains the clinker which is major constituent of the cement. The

cement contains 95 % clinker which is conveyed through weigh feeder to the main belt

conveyor which takes it to the cement mill. Remaining 5% material is gypsum and

additive material. The mixing of these materials takes place here.

The crushed gypsum from a separate crusher is conveyed by belt conveyor

to the cement mill. It is mixed in the clinker while crushing. Gypsum is added to about

5 %. Its purpose is to increase the settling time of the cement. The additive which is

pure limestone is also added in the cement mill, about 2% to increase strength of

cement.

Now cement is in the final stages and therefore its purity is ensured. This is

done by using metal detector to check if there is any left iron impurity or not. Other

sensors detect the presence of stones etc.

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5.18 CEMENT MILL

There are two cement mills at the plant and each of them has capacity of 175 tons/hour.

The motors that are used in cement mills are of 4300KW of power and

manufactured by FLSmidth.

The feed which is free from impurities falls on the table of cement mill which contains

three rollers. Each roller has weight of 35 tons and the clearance between table and

rollers is 0.5 mm. These rollers move hydraulically using nitrogen gas as hydraulic

fluid. The rollers crush the feed to a very fine powder. Then the air slides convey the

ground product to the bucket elevator which lifts it to enter into the 1st storage silo.

5.19 CEMENT SILO

There are three cement storage silos in which crushed cement is stored until packing.

To convey the cement to the other 2 silos air slides are used. From these silos the cement

enters air slides by air circulations through blowers. Now these air slides take the

cement to the packing plant.

Capacity of storage silos is 21,000 tons, length is 45 meters and diameter is 22.4 meters.

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5.20 PACKING PLANT

The packing plant comprises of six packers and 12 terminals. Each packer has a

capacity of 100 tons/hr. The cement bags are attached manually to the rotating packer

which fills the cement bag. When the bag is filled up to the required weight, it

automatically falls on the conveyor belt which takes the bags to the roller conveyor.

From these rollers the bags slide to different channels and finally cement bags are

loaded on the trucks for dispatch.

Weight Bridge:

Every truck or loader of cement that comes out from packing plant have to go for weight

if the weight exceed than a limit loader will be turned back for accuracy, so weight

bridge also plays an important role. The average weight of each bag is 50 ± 1.5 kg;

otherwise sensors being deployed recycle the bag back.

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6. CENTRAL CONTROL ROOM (CCR)

It is the nerve center of the cement plant since all equipment is controlled from this

place. It is the place from where all the process parameters are controlled.

All the processes in the plant are controlled through the CCR. Where inputs and outputs

are changed and whole plant is monitored. It is the nerve center of the cement plant

since all equipment is controlled from this place. It is the place from where all the

process parameters are controlled.

All the processes in the plant are controlled through the CCR. Where inputs and outputs

are changed and whole plant is monitored.

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7. LABORATORIES

There are following laboratories for the purpose of testing, checking and regulat ing

composition of material under process at various stages. So these are necessary to

ensure quality material at all stages.

1. Sample preparation Lab: Checks samples of material used in kiln.

2. Press Mill: Pressure exerted of 150 KN on dye which have material.

3. X-ray Analysis: X-ray analysis check determine the composition.

4. Chemical testing lab: It determines the time of consuming process.

5. Physical testing lab: Determine strength of cement samples.

8. PLC

Programmable Logic Control (PLC) is the main controlling area of the plant. So this is

the most important and critical part of the whole plant as each and every process

depends on this.

Plant is controlled by CCR (Computerized Control Room) which have different

sections like IT Dept., Exchange, Laboratories, Control Room, and PLC. PLC Dept.

have to look after that while every component in plant is working properly or not if

there will be any fault according to Automation they have to remove that. Plant has ten

major PLC’s main controlling PLC port is of SEIMENS Co Ltd. Signals send to control

room by underground wiring of cable Fiber optics also used for long distances.

9. WASTE HEAT RECOVERY PLANT

The total power requirement of the plant is about 34 MW. To meet the requirement the

DG have a power plant at khairpur. The plant have two Generators of about 12.5 MW

each running on the Fuel. The fuel used there is LFO and the natural gas for the engines.

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The DG cement group took a major and environment friendly step for the

power generation as well as environment protection. The project activity is the

installation of Heat recovery steam generators. The waste heat generated at the cement

plant in the clinker production process is vented to the atmosphere. In WHR plant this

heat is used as a fuel. The steam is produced with help of water according the famous

Kalina cycle. The steam with high pressure is used to run the turbine. The total

production of WHR at Khairpur plant is 8 MW. The total power requirement of the

plant is about 34 MW. To meet the requirement the DG have a power plant at khairpur.

The plant have two Generators of about 12.5 MW each running on the Fuel. The fuel

used there is LFO and the natural gas for the engines.

The DG cement group took a major and environment friendly step for the power

generation as well as environment protection. The project activity is the installation of

Heat recovery steam generators. The waste heat generated at the cement plant in the

clinker production process is vented to the atmosphere. In WHR plant this heat is used

as a fuel. The steam is produced with help of water according the famous Kalina cycle.

The steam with high pressure is used to run the turbine. The total production of WHR

at Khairpur plant is 8 MW.

10. SAFETY MEASURES

Following Safety Measures are observed there;

1. Safety Helmets (white for Engineers and yellow for sub engineers)

2. Ear bugs.

3. Safety boots.

4. Special uniform for workers.

5. Emergency Fire Exit.

6. Carbon Dioxide cylinders.

7. Fire Alarming system.

8. Fire Extinguishing Water pipes.

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11. FUTURE TRENDS OF PLANT

Examining the current state of art technology and nearly fully automatic control system,

one can easily accept that the future of this plant seems bright.

Automatic Control:

The overhead of man-power and demanding work of monitoring each and every thing

is not only difficult but also hectic tasks and more error-prone. This manual labor is

replaced by automatic control through electronics and programming techniques. PLC

serves the purpose of monitoring, regulating and alarming in case of deviations.

Reliable long communication:

PLC has to communicate and interact with the various devices and plants as well as

CCR. To make sure that the communication is reliable, fiber optics is being used for

this purpose.

12. CONCLUSION

I would bring this report to end by concluding my experience in the industry. It was my

first ever industrial tour and this was a great experience. Learning each and every thing

from books is a good thing but going out in field is a whole new thing. This is a crucial

thing and it teaches how to interact with colleagues and above all, one comes to know

how the field is like. I gain lot of knowledge about industries that will be helpful for

me in future. Being an engineer I simply got a direction for my future by this internship.

Finally I would like to thank all staff of DG Cement Khairpur plant for their help and

guidance. Every person at factory site tried to help the way he could in every possible

way.

I would be more than happy to work was internee with them if I get the chance of it.

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13. REFERENCES

www.google.com

www.wikipedia.com

www.sick.com/.../cement/Pages/cement.aspx

www.siamrefractory.com/cement_cyclone.php

www.lwbref.de/en/markets/cement-lime-industry/

internship report(zia ul hassan,13-me-01)

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