Internship Report HPFL 2012

Internship Report HPFL 2012

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INTERNSHIP REPORT

SCHOOL OF CHEMICAL AND MATERIALS ENGINEERING (SCME)

NATIONAL UNIVERSITY OF SCIENCES AND TECHNOLOGY

H-12 , ISLAMABAD


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1 DECLARATION

_____________________________________ July 30, 2012

TO WHOM IT MAY CONCERN Dear Sir:

Submitted for your review is the report of our internship at Production Unit of

Hazara Phosphate Fertilizer Private Ltd. Haripur Hazara plant, during July 2012.

It is hereby declared that the report is compiled in long report format, as per

the guidelines and is based upon the literature review; plant manuals and

standard operating procedures; process flow diagrams and sharing and

learning from management and staff of the company.

It is anticipated that response will be reflected.

Regards ,

Muhammad Zubair

Undergraduate Student

School of Chemical and Materials Engineering (SCME)

National University of Sciences and Technology (NUST)

H-12 Campus, Islamabad – 44000

2010 – NUST – BE – CHE– 19

Email: [email protected]

Contact: 0321-6711529

Kashif Nadeem

Undergraduate Student

School of Chemical and Materials Engineering (SCME)

National University of Sciences and Technology (NUST)

H-12 Campus, Islamabad – 44000

2010 – NUST – BE – CHE– 10

Email: [email protected]

Contact: 0341-7448894


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2 ACKNOWLEDGEMENTS

Author is thankful to

Almighty Allah,

For His unlimited blessings and bounties,

And for keeping him sane, sound and successful;

His parents and friends,

For all their support and trust in him and his aims;

His teachers and guides,

For teaching him things he knew not;

Lec Abdur Razzaq,

For bringing the opportunity of this excellent learning and exposure;

And last but never the least

Management and Staff of Hazara Phosphate Fertilizer Private Ltd

Especially Plant Managers, Shift Engineers and Operators,

For their utmost help, guidance and time

Which made author make most of his internship at plant site;


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INTRODUCTION

LOCATION OF THE PLANT

PURPOSE OF THE PLANT

SINGLE SUPERPHOSPHATE PLANT

SULPHURIC ACID PLANT

WATER TREATMENT PLANT

SAFETY

ANALYSIS LAB


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INTRODUCTION

Hazara Phosphate Fertilizers (Private) Limited (HPFL) is a public sector company.

HPFL is located in Haripur, NWFP 75 KM from Islamabad. The factory is situated

on 57 acres of developed land, and includes factory, housing and other

amenities. HPFL was incorporated under the Companies Ordinance 1984 in June

1985 as a private limited company and commenced commercial operation in

1989.

HPFL is operating in the fertilizer industry and manufactures Granulated Single

Super Phosphate (GSSP) fertilizers using a combination of indigenous phosphate

rock from the Kakul mines in proximity of plant and imported rock from Jordan

and Morocco. Since 1999 rock phosphate is being imported mainly from Jordan

for manufacture of GSSP, because of non-availability of local rock phosphate.

HPFL has authorized share capital of Rs.200 million divided into 20 million

ordinary shares of Rs.10 each. Out of these 19,143,207 ordinary shares have

been issued, subscribed and fully paid up as on June 30, 2007.

National Fertilizers Corporation (NFC) holds 100% equity in HPFL. NFC was

incorporated as a private limited company on August 11, 1973, with an

authorized share capital of Rs.1,000 million, which was subscribed entirely by

the Government of Pakistan.

Operational management comprises of a Managing Director and General

Manager. Total personnel strength of regular staff plus daily wages labour as at

June 30, 2007 was 261.

The break down of staff is given as under;

Management / Executives 35

Non-Executive 88

Daily Wages Labour 138


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LOCATION OF THE PLANT

HPFL is located in Haripur, KPK 75 KM from Islamabad. The factory is situated

on 57 acres of developed land, and includes factory, housing and other

amenities.

PURPOSE OF THE PLANT

To produce single super phosphate to keep the agricultural system of our

country up right and to ensure maximum production of crops.

.


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SINGLE SUPERPHOSPHATE PLANT


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SINGLE SUPERPHOSPHATE PLANT:

Single Super Phosphate Plant consists of Three separate units namely

Run of Pile (ROP) section

Granulation plant(GP) Section

Bagging section

ROP SECTION:

ROP section consists of following parts :

Crusher

Hopper

Bucket elevator

Level hopper

Feeder

Grinding mill

Cyclones

Screw conveyor

Main bucket elevator

Main hopper

screw conveyor

Dosimeter

Acid dilution unit

Mixer

Drum den

Leather conveyor

Storage


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RAW MATERIAL

Raw material taken is containing about 10% phosphate content and is taken

from Kakul . This phosphate cannot be taken by plants and is not taken uproot

by the plants . Raw material is transported to the plant by trucks . The material

is weighed in the weighing place . Now the material is unloaded into the

crusher which crushes it to about 4-5 mm in size . This size is enough for the

feed to the mill . A storage is present on the plant to store this raw material to

ensure a good stock for the batch preparation .

The basic purpose which we have to do is to make the phosphate soluble , so

that it can be easily used in the soil . In Run Of Pile (ROP) system , basically all

physical processes are taking place and the raw material is mixed with

sulphuric aicd to make it a substance which has a phosphate which can be

readily absorbed by the crops . Fine groundeng of the material ensures that the

material gets easily mixed with the sulphuric acid .

The phosphorus content of the raw material is checked in the laboratory for

further calculations and the batch preparation . This is necessary because we

want about 16% amount of soluble phosphorus at the end .


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CRUSHER:

A crusher is a machine designed to reduce large rocks into smaller rocks,

gravel, or rock dust. Crushers may be used to reduce the size or change the

form of waste materials. Crusher is a mechanical machine which is used to

reduce the size of the raw material up to 30 mm. This is run by an electric

motor of 5KW. First of all raw material from the field is brought to the hopper

which is connected to the jaw crusher. This feed is in the form of lumens and

pills. These lumens are required to be crushed to get a suitable feed size which

is about 30 mm. For this purpose jaw crushers are used in the industry. Jaw

crushers crush the feed to our required size. This feed is then stored in the

storage room. A jaw or toggle crusher consists of a set of vertical jaws, one jaw

being fixed and the other being moved back and forth relative to it by

a cam or pitman mechanism. The jaws are farther apart at the top than at the

bottom, forming a tapered chute so that the material is crushed progressively

smaller and smaller as it travels downward until it is small enough to escape

from the bottom opening. The movement of the jaw can be quite small, since

complete crushing is not performed in one stroke. The inertia required to crush

the material is provided by a weighted flywheel that moves a shaft creating an

eccentric motion that causes the closing of the gap.

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http://en.wikipedia.org/wiki/Cam

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HOPPER

The material is then fed to a hopper for feedeng the mill in a continuous form .

For this purpose loaders are used . The hopper is a trapezoid shaped bucket

which has a vibrator at the bottom . Hopper serves as starting part of the mill

and to make the process run smoothly . It is made of mild steel to bear the raw

material .

The vibrator is actually a built system in which a 5 KV motor is used to rotate

an assembly in which a gear box is attached to the lower side of hopper . Now a

weight is attached to the gear attached to the hopper to cause an imbalance in

the motion which is the cause of vibration of the hopper .

Due to the vibrator system the feed does not get stuck in the hopper and in this

way it moves to the next section easily . The hopper is manually controlled ,

and when ever the feed to the mill is required it can be run by the push of a

button.

The construction of the hopper is hereby explained :-


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BUCKET ELEVATOR

A bucket elevator, also called a grain leg, is a mechanism for hauling flowable

bulk materials (most often grain or fertilizer) vertically.

It consists of:

1. Buckets to contain the material.

2. A belt or chain to carry the

buckets and transmit the pull;.

3. Means to drive the belt.

4. Accessories for loading the buckets or

picking up the material, for receiving

the discharged material, for maintaining

the belt tension and for enclosing and

protecting the elevator.

The material from the hopper then goes into the bucket elevator and is elevated

to a height. The bucket elevator is driven by a 5 KV motor . The buckets are

basically curved rubber pads to carry material . At the lower end of the bucket

elevator , there are openings for the inspection of the buckets , because worn

out and broken buckets can be a serious hazard to the assembly of the

elevator.

Maximum care is needed to be taken for making the elevator air tight to

decrease the chances of emission of dust When material enters the bucket

elevator it gets on the buckets in small amounts . Each bucket takes a small

amount of material and takes it to the highest level . At getting upside down ,

the material falls onto the feeder .

LEVEL HOPPER:

After the bucket elevator the raw material is then store in the level hopper

which is connected to the feeder. This hopper maintain the level of the raw

material for the grinding mills and he feeder. This hopper consists of a

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http://en.wikipedia.org/wiki/Fertilizer

http://en.wikipedia.org/wiki/Bucket_(mechanical_engineering)


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vibrating motor which is joined to the external wall of the hopper so that if the

feed is wet then it cannot stick to the walls of the hopper to the internal side.

FEEDER

The material now falls from the elevator into the feeder . It has a capacity of

about 3 tonnes. It is fiited with a system which tells when it is totally filled to

required level and a bulb glows , so its intake can be stopped .

The feeder is fitted with an electromagnet . This electromagnet ensures the

required amount of material is fed to the mill and it also gives the vibrational

force for uniform feedeng.

The dust factor is low , but further it is sealed by the rubbers to seal the feeder

, in this way less dust goes to environment .

If there is a problem in the mill , the exit from the hopper can be controlled to

ensure the safety factor .


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GRINDING MILL:

Grinding mill is the important part of the ROP

section. The mill section also consist of the

following objects:

Grinding mill body

Six grinding rollers

6 blow plates

6 safety plates

Motor and gear box

Classifier

Blower and motor

Candle filter

Working of the Grinding mill:

Grinding mill grind the raw material to the fine powder. The mills that are used

for this purpose are the vertical roller mills. The roller mill works on the

principal of the compressive and shear force. It consists of six rollers that are

assembled together with the help of main shaft. That shaft is rotated with the

help of gear box and motor of 132 KW. The Mill’s main shaft rotates about 84

RPM. The rollers are connected with the help of spring. The spring provides the

necessary centrifugal force to the rollers. There is a small clearance between

the rollers and the wall of the mill. When the roller s rotates the material is

grinded between the rollers and the wall of the mill. Blow plates keep the level

of the raw material to the roller to grind. Safety plates keep the body of the mill

safe from any damage during grinding because material sticks the wall of the

mill. In this way material strikes to the safety plates and the damage plates can

be replaced easily. Motor and gear box helps to rotate the main shaft and the

roller. Blower is run with the help of the motor of same power. Blower mainly

does two main works. First this creates the section and it deliver the grinded


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material from the bottom of the mill to the cyclone with the help of the

pressure created by the blower. Secondly it creates the –ive pressure of 0.22

bar in the inlet of the mill so that no dust can move to the open surroundeng.

The blower joined through the mill and the cyclones in air tight dockets in a

close loop.10 % of this dust in these dockets are ejected to the soundeng by

passing it through the candle filters so that these dockets cannot be chocked

After some time the candle paper are cleaned for good filtering. Classifier in the

mill rotates with the help of a motor. It allow a specific size particle to move

upward and the oversize particle though in to the mill again. Any fault in the

mill is indicated with the help of the ampere meter in the control room. The

whole assembly of the mill is shown in the fig.


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CYCLONES:

Cyclones are the conical cylinder connected to the blower and the mill. The

grinded material from the mill is transfer to the upper inlet of the cyclone

with the help of the blower. The relatively larger particle loss there energy

there and fall down in the cyclone and the small practical like dust come

back to the blower in the closed loop. The main function of the cyclones are

to separate the larger piratical from the dust. The fig is given below:

Actuators allow the specific amount of the material from the bottom of the

cyclone to the screw conveyor. Two actuators acts in such a ways that first

material fall on the first actuators, it opens due to the weight of the material.

Meanwhile other actuator is close due to the mechanical load attached to

it.When the material fall on the second actuator the first on closed so the there

is no leakage of the developed section in the closed loop of the blower.


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SCREW CONVEYER

The material from both the cyclones falls on the screw conveyer . The screw

conveyers are simple yet effective for the transport of materials. The material

when falls , it gets between the pitch of screw and in this way the rotation of

the screw in the conveyer moves the material to the other end . They are

covered from top , to ensure that no dust is leaked from the conveyer into

atmosphere. These conveyers have low operational cost and very less wear and

tear . Screw conveyers are run by 3KV motors.

MAIN BUCKET ELEVATOR AND STORAGE

Material from the screw conveyers goes onto the main bucket elevator which

moves the material to the top floor . It is run by a 5KV motor, it is now ready to

be mixed with sulphuric acid . From here there are two more screw conveyers at

the top to move material to a storage to ensure the material comes in

continuous form once the mixing is started. The storage serves as a feeder to

the dosimeter.


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DOSIMETER:

Dosimeter is a mechanical device which measure the amount of the material

which is convey to the mixer. It is simply a conveyor run by an electric motor of

5 KW. It operating flow rate is about 10054 Kg/h. It takes the material from the

main hopper and drop this this material to the mixer.

ACID DILUTION UNIT

Acid use in the formation of SSP requires is about 68 to 70%. We have 98.5%

acid store in the storage tank. So we have to dilute this acid for the best result.

This is done in the Acid dilution unit. The process of dilution of sulphuric acid

is an exothermic process . This evolves a reasonable amount of heat which is to

be removed before the mixing of this acid .

For this purpose a block heat exchanger is used. Acid solution is moved from

the pipe in many passes and the water in the surrounding of these pipes is

passed to cool the acid solution. Countercurrent flow ensures maximum heat

transfer .The total surface area of the Block is 11.8 m2. In this way we get our

require degree of dilution of the acid.

MIXER:

In mixer acid 68 % and the raw material mix to each other. Mixer consists of a

shaft with 12 paddles and a electric motor. This shaft and the paddles are

closed in a container .Raw material enter the mixer from the dosimeter and acid

is shower from the upper side of the container. The motor rotate the shaft and

the paddles which mix the acid and rock. In this way acid and rock mix to each

other in the uniformly and chemical reaction occur hear. Tricalcium phosphate

converts in to single calcium phosphate.


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DRUM DEN (20WA01):

After the mixture the material s passed through the drum den. Drum den

rotates at a specific RPM. The material from the mixer is now calling ROP. This

ROP pass through the Drum den which is rotates with the help of an electric

motor, Drum den also help in the mixing of the acid and rock and also give

some time to reaction so that maximum HF gas is produce here and it can be

scrub by scrubbings unit.

LEATHER CONVEYOR STORE:

After the drum den ROP falls on leather conveyor which conveys the ROP to

the store for 2 to 3 weeks. In these days the reaction of acid and rocks

complete and the complete ROP is formed. We find the competition of

reaction by findeng the free acid in the ROP. In the ROP there must be 12 %

free acid should present in the final ROP.


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ROP SCRUBBING UNITS:

The main purpose of the ROP scrubbing units is to scrub the HF gas and the

other gases and the dust create in the drum den so that these gases does not

create the pollution in the atmosphere. For this we use three venture scrubbers

and three cyclonic scrubbers. First of all the HF and other gases are withdrawn

from the drum den with the help of the 20K01 blower. These gases venture

20C02A where water is shower from the top and the gases are dissolved in this

water. Then reminder gases go to the first cyclonic scrubber from the bottom

and the water is shower from the top and the gas then also dissolved in the

water. In this way we use three venture scrubbers and three cyclonic scrubbers

in series in alternate manners. In the end the wash air then exits to the

atmosphere through the 20F05 chimney.


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PROCESS OF ROP SECTION:

First of all the raw material in the form of large stone is grinded with the help of

the jaw crusher and store the material in the store. The sample of the raw

material is taken and tested in the Chemical Lab and find the amount of the P in

the raw material. If the %age of the P is below then 14% then we add TSP or DAP

to maintain the amount of the P to14% in the feed. Then this feed is convey to

the hopper by the loaded. Feed from the hopper reach the grinding mill

through the bucket elevator ,level hopper and feeder. Grinding mill is the

vertical roller mill which consists of 6 rollers. This mill grinds the feed to the

fine powder. This grinded material goes to the cyclone through the classifier

and the different dockets with the help of the Blower. The size of the grinded

material is up to -270 to -280 mesh. This material goes to the main hopper

with the help of main bucket elevator and screw conveyor. Then material moves

tower the mixer through the dosimeter and acid id added to the feed and

reaction is occur in the mixer and drum den. After drum den the ROP moves

tower the ROP storage through conveyor 11,12, and 13.the HF gas and other

dust moves tower the scrubbing section with the help of blower.

GENERAL STARTUP PROCEDURE:

Before starting the ROP section ,it is necessary to visit all the section and

conveyor of the plant. Confirm it that all the parts are ready.Then start the

section as

1. Start belt conveyor 13



4. Start the drum den

5. Start the mixer And supply of the acid


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6. Start 20N01

7. Top screw conveyor

8. Main bucket elevator

9. Screw conveyor

10. Classifier

11. Blower

12. Grinding mill

13. Hopper motor

GENERAL SHUTDOWN PROCEDURE:

Stop the section in the following manners:

1. Hopper

2. Blower

3. Classifier

4. Screw conveyor

5. Bucket elevator

6. Top screw conveyor

7. 20N01

8. Mixer

9. Drum den

10. Belt conveyor 11




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GRANULATIONS PLANT(GP) SECTION

GP section consists of the following parts:

ROP hopper

Jaw crusher

Belt conveyor

ROP main hopper

Main belt conveyor

Granulator

Furnace and dryer

Double docket screen

Hammer crusher

Product belt conveyor

product storage

ROP HOPPER:

The Rop after the 2 to 3 weeks placed in the ROP hopper with the

help of the loader in the ROP storage room. This hopper vibrates with the help

of the electric moter with unbalance centrifugal force and the spring.

JAW CRUSHER:

The ROP from the hopper comes to the jaw crusher. This crusher crush the ROP

to a specific size.This crusher runs with the help of the Electric motor. Actually

the ROP converted in to large lumens and they are required to crush them for

the granulator.


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BELT CONVEYOR AND ROP MAIN HOPPER:

After the crusher the ROP goes in to the main ROP hopper through Belts

conveyorsand finally fall in to the main hopper. The level of the hopper is auto

control . When the level of the ROP increases in the main hopper the system

closed the belts conveyor and the more supply of the ROP stops .After the level

decrease the conveyors run automatically.

MAIN BELT CONVEYOR (20 WE 15):

The ROP from the main hopper falls on the main belt conveyor. This conveyor is

very important because all the Dust practical, oversize, undersize and other

ROP falls on this conveyor. This conveyor feed the Granulator.

GRANULATOR:

Granulator is the very important part of the GP section. It is a cylindrical

shaped drum rotated with the help of the electric motor. It works in such a

way that the ROP from the main conveyor falls in the Granulator and a small

amount of the water is also added in the ROP in it. The amount of the water is

control manually. The amount of the water helps to the ROP to gain granular

shape. The shape of the ROP is form by the restoring force of the rubber wall

of the Granulator.

FURNACE AND DRYER

Furnace and dryer consist of the following parts:

Air blowers (20 K 07 and 20 K o8)

Furnace body

Dryer

Dryer motor and gear box


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First of all start the furnace and the two blowers. First blower builds the flame

of the fire in the furnace and other gives the air to produce the hot air for the

drying .The inlet temperature of the furnace is about 1000C and the

temperature on the outlet of the furnace is about 3000C.This high temperature

create the hot air.

The wet ROP from granulator then goes in the dryer. The hit air comes in

the dryer from the furnace. The dryer rotate at a specific rate with the help of

motor and gear box. Hot air dry the wet ROP. The moisture at the end of the

dryer should be about 5-6%. Then the hot SSP is put in the bucket elevator to

the top floor.

DOUBLE DOCKET SCREEN:

After the main bucket elevator the place a Double docket screens to separate

the oversize and undersize product and our actual product. The double docket

screen has two meshes on one another. The first on has a hole of 6 mm2.It

allow the product of size less than 6mm2 to pass it. Larger size particles not

pass through it and they are called over size product. This oversize product

goes tower the hammer. The second mesh has a hole of 1mm2. It allows the

material of this size to pass it. This material is called under size and this goes

tower the main belt conveyor for recycling. The product size between 6 and

1mm2 is our actual product. This product goes tower the product storage

through the belt conveyor.

HAMMER CRUSHER:

The oversize product comes in the hammer crusher. Hammer crusher crush the

material and past this material the main conveyor for recycling. Hammer

crusher consists of a roller and 36 hammers. The roller and hammers are

rotated in the opposite side. The material falls on the drum and the hammer

strikes the material with great impact .Due to this force the material breaks

down into small pieces. The crusher is run by the motor.


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PROCESS OF GP SECTION:

First of all the ROP in the storage is loaded in the hopper with the help of

loader. The material form hopper moves to the jaw crusher. Crusher crush the

material to a specific size and then material is moves tower the main ROP

hopper with the help of belt conveyor. From hopper the material goes to the

granulator where it changes in the form of grains. These granulated material

moves tower the dryer. In dryer the wet material dry with the help of hot air

coming from the furnace. The dry material from the dryer goes to the Mesh

through the bucket elevator. Double mesh classifies the mater in to under size,

oversize and product. Oversize goes tower the hammer crusher. Where the size

of the material reduce with the help of hammer. Then this material goes to the

main belt conveyor for recycling. The under size material goes to the main belt

conveyor for recycle. The product goes tower the storage room through the

product conveyor.

GP SCRUBBING UNITS:

In GP section it is necessary to wash the dust and other gases to keep the

surrounding clean. So like ROP section we also scrub all the dust of GP section

also. In GP section There are three scrubber section.

1. The dust created in the granulator 20 WA 02 is drawn from it by the

section created by the blower 20K04.This dust is first pass through the

venture 20C05 where water is shower from the above side. Dust is

dissolved in the water and the mixture of dust and water goes to the tank

20T02.After that the remaining air is passes through the tower 20G06

where water is also shower through the top of the tower. The most of the

Gases dissolved in the water and pure air is exited to the atmosphere.

2. The dust and gases created in the dryer is also passes through the

cyclones 20 JC 01 A,B with the help of the section created by the blower


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20K02.this dust and gases goes in to the venture 20C04,where water is

shower from the top of the venture. Dust and gases are dissolved in the

water. Then these remaining gases go to the tower 20G06.where these

gases more washed by the shower of the water. Pure air is exited to the

atmosphere. Over size material in the bottom of the cyclones goes to the

main belt conveyor for the recycling.

3. The dust created by the different belt conveyors, by hammer crusher, by

the Mesh is collected by the section created by the blower 20K04. This

dust is first passed through the cyclone 20JC02.The oversize practical in

the cyclone go tower the main conveyor for recycling. The dust then

moves tower the tower 20G06.where water is shower from the top of the

tower and dust id dissolved in the water and pure air is exited in the

atmosphere.

The water from the tank 20T02 and from tower 20G06 then goes to the water

treatment plant.

GENERAL STARTUP PROCEDURE OF GP SECTION:

First of all visit the GP section and check all the units and ensure it that all are

ready for the process. Then start the every unit according the given manner:

1. Start the product belt conveyor

2. double docket screen

3. Hammer crusher

4. Bucket elevators

5. Dryer

6. Furnace

7. Granulator

8. Main belt conveyor

9. ROP belt conveyor

10. Jaw crusher


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11. Hopper

GENERAL SHUTDOWN PROCEDURE FOR GP

SECTION

Stop all the units according to the following manners:

1. Hopper

2. Jaw crusher

3. ROP belt conveyor

4. Main belt conveyor

5. Granulator

6. Furnace

7. Dryer

8. Bucket elevators

9. double docket screen

10. Hammer crusher

11. Product belt conveyor


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BAGGING SECTION

This section consists of

product hopper

product conveyors

product storage hopper

mechanical balance

sewing machine

Bagging section consists of a hopper and belt conveyors and a balance. The

product is loaded in the hopper with the help of loader. This product goes to

the storage hopper. The mechanical balance took the product from the hopper

and weighs it and drop 50 Kg of the product to the polymer bag. The

mechanical balance has two portions. When on portion drop the product in the

bag the other portion get material from the storage hopper. These two portions

works in the alternative manner. The polymer bag after getting material are

sealed and loaded to the trucks with the help of conveyor and men labor.


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SULPHURIC ACID PLANT (SAP)


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SULPHURIC ACID PLANT (SAP):

INTRODUCTION:

Sulfuric acid (alternative spelling sulphuric acid) is a

highly corrosive strong mineral acid with the molecular formula H2SO4. It is a

colorless to slightly yellow viscous liquid which is soluble in water at all

concentrations.

Sometimes, it may be dark brown as dyed during industrial production process

in order to alert people's awareness to its hazards. The historical name of this

acid is oil of vitriol.

It is a diprotic acid which may show different properties depending upon its

concentration. Its corrosiveness on metals, stones, skin, eyes and flesh or other

materials can be mainly ascribed to its strong acidic nature and, if

concentrated, strong dehydrating and oxidizing properties.

Concentrated sulfuric acid can cause very serious damage upon contact as not

only does it hydrolyze proteins and lipids leading to chemical burn, but also

dehydrates carbohydrates resulting in secondary thermal burn. If it

contacts eyes, permanent blindness may occur So, safety precautions should

always be taken when using it. Moreover, it is hygroscopic, readily

absorbing water vapor from the air.

Possessing different chemical properties, the sulfuric acid has a wide range of

applications including domestic acidic drain cleaner electrolyte in lead-acid

batteries and various cleaning agents.

It is also a central substance in the chemical industry. Principal uses

include mineral processing, fertilizer manufacturing, refining, wastewater,

and chemical synthesis. It is widely produced with different methods, such

as contact process, wet sulfuric acid process and some other methods.

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http://en.wikipedia.org/wiki/Stones

http://en.wikipedia.org/wiki/Skin

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http://en.wikipedia.org/wiki/Flesh

http://en.wikipedia.org/wiki/Strong_acid

http://en.wikipedia.org/wiki/Dehydration

http://en.wikipedia.org/wiki/Oxidizing_agent

http://en.wikipedia.org/wiki/Proteins

http://en.wikipedia.org/wiki/Lipids

http://en.wikipedia.org/wiki/Chemical_burn

http://en.wikipedia.org/wiki/Carbohydrates

http://en.wikipedia.org/wiki/Eyes

http://en.wikipedia.org/wiki/Blindness

http://en.wikipedia.org/wiki/Hygroscopic

http://en.wikipedia.org/wiki/Water_vapour

http://en.wikipedia.org/wiki/Air

http://en.wikipedia.org/wiki/Drain_cleaner

http://en.wikipedia.org/wiki/Electrolyte

http://en.wikipedia.org/wiki/Cleaning_agent

http://en.wikipedia.org/wiki/Chemical_industry

http://en.wikipedia.org/wiki/Mineral_processing

http://en.wikipedia.org/wiki/Fertilizer

http://en.wikipedia.org/wiki/Chemical_synthesis

http://en.wikipedia.org/wiki/Contact_process

http://en.wikipedia.org/wiki/Wet_sulfuric_acid_process


32

GRADES OF SULFURIC ACID

Although nearly 99% sulfuric acid can be made, this loses SO3 at the boiling

point to produce 98.3% acid. The 98% grade is more stable in storage, and is

the usual form of what is described as "concentrated sulfuric acid." Other

concentrations are used for different purposes.

"Chamber acid" and "tower acid" were the two concentrations of sulfuric acid

produced by the lead chamber process, chamber acid being the acid produced

in lead chamber itself (<70% to avoid contamination with nitrosylsulfuric acid)

and tower acid being the acid recovered from the bottom of the Glover

tower They are now obsolete as commercial concentrations of sulfuric acid,

although they may be prepared in the laboratory from concentrated sulfuric

acid if needed. In particular, "10M" sulfuric acid (the modern equivalent of

chamber acid, used in many titrations) is prepared by slowly adding 98%

sulfuric acid to an equal volume of water, with good stirring: the temperature of

the mixture can rise to 80 °C (176 °F) or higher.

Massfraction

H2SO4

Density

(kg/L)

Concentration

(mol/L) Common name

10% 1.07 ~1 dilute sulfuric acid

29–32% 1.25–1.28 4.2–5 Battery acid(lead–acid batteries)

62–70% 1.52–1.60 9.6–11.5 Chamberacid fertilizer acid

78–80% 1.70–1.73 13.5–14 tower acid Glover acid

98% 1.83 ~18 concentrated sulfuric acid

http://en.wikipedia.org/wiki/Sulfur_trioxide

http://en.wikipedia.org/wiki/Lead_chamber_process

http://en.wikipedia.org/wiki/Nitrosylsulfuric_acid

http://en.wikipedia.org/wiki/Titration

http://en.wikipedia.org/wiki/Lead%E2%80%93acid_battery


33

Sulfuric acid reacts with its anhydride, SO3, to form H2S2O7, called pyro sulfuric

acid, fuming sulfuric acid, Disulfuric acid or oleum or, less

commonly, Nordhausen acid. Concentrations of oleum are either expressed in

terms of % SO3 (called % oleum) or as % H2SO4 (the amount made if H2O were

added); common concentrations are 40% oleum (109% H2SO4) and 65% oleum

(114.6% H2SO4). Pure H2S2O7 is a solid with melting point 36 °C.

Pure sulfuric acid is a viscous clear liquid, like oil, and this explains the old

name of the acid ('oil of vitriol').

Commercial sulfuric acid is sold in several different purity grades. Technical

grade H2SO4 is impure and often colored, but is suitable for making fertilizer.

Pure grades such as United States Pharmacopeia (USP) grade are used for

making pharmaceuticals and dyestuffs. Analytical grades are also available.

Sulphuric acid is the basic and very important raw material use in the

formation of SSP in the ROP section. Sulphuric acid is transport from the acid

storage to the SSP plan through the stainless steel pipes. The temperature and

the concentration of the acid kept on a specific to avoid the corrosion in the

pipes.

http://en.wikipedia.org/wiki/Pyrosulfuric_acid

http://en.wikipedia.org/wiki/Pyrosulfuric_acid

http://en.wikipedia.org/wiki/United_States_Pharmacopeia

http://en.wikipedia.org/wiki/Pharmaceutical

http://en.wikipedia.org/wiki/Dye

http://en.wikipedia.org/wiki/Analytical_chemistry


34

BASICS UNITS OF THE SULPHURIC ACID PLANT:

Hopper and belt conveyor

Melting pit

Filtring pit

Storage pit

Sulphur feed pumps

Sulphur gun

Drying chamber

Sulphur burning chamber

Waste heat exchanger

Four bed contact chamber

Steam storage

Waste heat boiler

Cold gas heat exchanger

Hot gas heat exchanger

Economizers

Inter absorption tower

Final absorption tower

Acid circulation tank

Pipe collars

Storage tanks

HOPPER AND BELT CONVEYOR:

Raw material from the storage is then feed to the hopper. Hopper is a

trapezium shaped pot which has larger cross-sectional area on upper side and

the area decrease as we move from the top to bottom of the hopper. This

hopper feed the melting pit by the belt conveyor.Best conveyor is a best mover

on the rollers with the help of motor. When the level of the sulphur reach to its

maximum level ,the conveyor stop. When the level of the sulphur is down to the

specific level ,it start again and transfer sulphur in to the melting pit.


35

MELTING PIT:

Milting pit is a small room where the sulphur is melted with the help of the

steam. Steam is provided from the stem storage tank. The pit consist four helix

of steam pipes in four corners. Steam of 7 bar moves through these pipes. The

sulphur in the pit is melted by gaining the heat from this steam. In working

condition the inlet valve open fully but the outlet valve is open partially. In this

way steam gets more time to transfer heat and melt more sulphur. The melting

temperature of the sulphur in the melting pits keeps 1250C.Above this

temperature the sulphur change in to plastic sulphur and its viscosity increases.

The sulphur in the pit is moves with the mechanical stirrer. In this way Heat

from the steam pipes also reach in the center of the pit and molten sulphur

does not stick on the wall of the steam pipes.

FILTERING PIT:

Filtering pit is like the melting pit in shape. It also consists of for steam pipes

and a mechanical stirrer. The overflow molten sulphur in the melting pit then

moves to the filtering pit. In filtering pit molten sulphur is then filter by the

filtration chamber. All the steam pipes are coated with glass wool to minimize

the heat losses. Filtration chamber is a simply a hopper type cylinder having a

steam coated body. It consists of three leaf filter in series. The molten sulphur

from the filtering pit can pumped through these filter. Molten sulphur pass

through these filter and mud is separate from the sulphur. This mud falls down

through the filtration chamber. The steam coating prevents the sulphur to

solidify in the filtering chamber. After some time the leaf filter are cleaned to

get proper filtration. The temperature of the filtering pit is about to1280C.

STORAGE PIT:

After the melting pit the molten sulphur moves tower the storage pit. Storage

pit also contain the steam pipes to avoid the solidification of sulphur again .The

pressure in the steam lines is about 4 bar and the temperature of the molten

sulphur is 125 to 1300C in the storage pit. Storage pit contain the pure sulphur.


36

SULPHUR FEED PUMPS:

The storage pit contains three pumps. There are two gear pump and one

centrifugal pump.This pump supply the molten sulphur to the sulphur gun with

high pressure. Some time ago there are two centrifugal pumps and one gear

pump. In the normal operation only one pump is in working condition and the

other two are on standby condition. These pumps are controlled by the control

room.

SULPHUR GUN:

Sulphur gen is made of iron. It is also coated with the steam pipes so that no

steam shuld solidify in the gun. The tip of the gen is about 5 mm in

circumference. Some time ago this tip is about 4mm.Due to the larger

production the tip size of the gum has increased. This gun received the molten

sulphur from the pumps of the storage pit with high pressure. This gun spread

the molten sulphur in the sulphur burning chamber.

DRYING CHAMBER:

Drying chamber is cylindrical tower which contain packing in it.First of all at the

bottom of the tower there is a layer of rashing ring of the diameter of 6 in. After

there is a layer of ceramic saddles of the thickness 1.8 meter. These ceramics

saddles are placed randomly. After this packing there is again a layer of rashing

rings on the top of the tower.

A Blower of the type of the double stage centrifugal type compressor is run by

the motor to give the air for sulphur burning in the sulphur burning chamber.

The pressure created by this compressor is 0.44 mbar. The rotation of the

blower is about 3000 RPM.This collect the air from the atmosphere. This air

contains 21 % oxygen and 79 % nitrogen. This air also contains the moisture in

it. It is necessary to remove this moisture. For his purpose we use drying tower.

This air is introduced in the tower from the bottom and the sulphuric acid is

shower from the top of the tower. Sulphuric acid absorbed the moisture from


37

the air and dry air goes to the sulphur burning chamber. The packing increase

the surface and contact of the acid and air. At the top of the tower there is mist

eliminator. Mist eliminator removes the mist of air and acid. After the process

the air remove from the top of the column and the acid remove from the

bottom of the column. Ceil pot contain the sulphuric acid. It remove the acid

from the mist eliminator but does not allow to mover air from the ceil pot.

The internal wall of the cylinder is coated with rubber chlorinated paint and

then there is a lining of the stainless steel bricks. This patron saves the tower

from any acid attack and corrosion.

SULPHUR BURNING CHAMBER:

The molten sulphur from the sulphur gun is introduced in to the chamber and

dry air is introduced from the drying tower. The molten sulphur burn in the

presence of oxygen. The molten sulphur reacts with oxygen to for the sulphur

dioxide gas. The %age of SO2 and the oxygen must be in such a way that if

there is 10% SO2 then the oxygen will be 11%.The sum of these two %ages

should be equal to 21 % for the good process. The temperature of the sulphur

burning chamber is about to 1080 0C.

WASTE HEAT EXCHANGER:

Waste heat exchanger is a fire tube boiler. It consists of 169 tubes and a shell.

The hot gases from the sulphur burning chamber are then passes through the

tubes of the exchanger. The temperature of the gases is about to 1080oC.In the

shell of the exchanger we pass water and in the tubes we pass hot gases. Heat

transfer occurs from hot gases to the cooled water in the shell and steam is

produced. The inlet temperature of the hot gases is 10800C and at the outlet

temperature is 3800C.In this way we produce the steam for our process and we

get the required temperature of the SO2 gas for the convertor.


38

STEAM STORAGE:

Steam storage is a horizontal chamber. The steam produce in the waste

heat exchanger is then store in this storage. It can bear a maximum

pressure of 15 bar. Extra steam is exit to the atmosphere if the pressure in

the storage increases through the safety valve.

FOUR BED CONTACT CHAMBER:

Four bed contact chamber has four chambers. First chamber consists of

the grating and a layer of the aluminum rings. The catalyst V2O5 in the

form of rings is placed in this section. Catalyst is coated with silica to

prevent from breaking and other actions. The tag of the catalyst is 110 and

it contains 10 V. The gases from the heat exchanger inter in the first

chamber and SO2 react with oxygen to produce SO3 gas. Maximum

conversion of SO2 is occurring in this chamber. The temperature of the

entering gases to the chamber is 4150C and the leaving from the first

chamber is 6100C.Because the energy release in this reaction and

temperature of the leaving gases increase. These gases then leave from the

chamber first. After passing the through the waste heat exchanger this

gases inter the 2nd bed at temperature 4400C .again second best has the

same construction as the first one. Remaining SO2 gas reacts with the

oxygen gas and form SO3 gas. After that these gases also leave at

temperature 5320C.This bed contain 111 catalysts which contain 11 V.In

the same manner 3rd and 4th bed acts and achieve the maximum

conversion. The inlet temperature of the 3rd bed is about 4500C and the

outlet temperature is about 4800C. The inlet temperature of the 4th bed is

about 4000C and the outlet temperature is about 4120C.


39

WASTE HEAT EXCHANGER:

Waste heat exchanger is a shell and tubes heat exchanger. The gases that

release from the 1st bed required cooling them by this exchanger, the

gases passes through the tubes and water passes through the shell of the

exchanger. In this way heat is transfer from the hot gases tower the cool

water. Steam is produce and this heat is transfer in to the steam storage.

There are 139 tubes in this shell. The temperature difference between the

hot inlet and hot outlet is about 2300C.

COOL GAS HEAT EXCHANGER AND HOT GAS

EXCHANGER:

These exchangers are also tube and shell heat exchangers. They cool the

gases coming from the 2nd and 3rd bed respectively. In the tube side we

take the mixture of gases but in the shell side we take SO2 gas from the

inter absorption tower in the shell side. This gas has very low temperature

we have to increase the temperature of this gas. In this way we transfer

heat from the hot gases tower this cool gas. This gas then goes to the 4th

bed.

ECONOMIZERS:

Economizers are also a type of shell and tube heat exchanger. There are

two Economizers in the plant. These Economizers perform two works. First

the reducer the temperature of the exit gas from the 3rd and 4th bed to

achieve the better absorption. Secondly the heat up the boiler water feed.

Water is moving in the tubes and the gases are in the shell of the

exchanger. Due to the heat transfer we get the required temperature.


40

ABSORPTION TOWER

There are two Absorption tower namely inter Absorption tower And final

Absorption tower. Inter absorption tower absorbe the gases coming from the

first economizer. Final absorption tower absorve the gases from the 2nd

economizer.

Absorption towers is cylindrical tower which contain packing in it.First of all at

the bottom of the tower there is a layer of rashing ring of the diameter of 6 in.

After there is a layer of ceramic saddles of the thickness 1.3 meter. These

ceramics saddles are placed randomly. After this packing there is again a layer

of rashing rings on the top of the tower.

In the inter absorption tower gases is introduce from the bottom to the tower

and aid is shower from the top. Acid absorbed the gas and form the olium.

Absorbable SO2 gas go to the 4th bed and in the final tower the gas come from

the 4th bed to the final absorption tower. In final absorption tower final

absorption occurd. The remaining gases and air then exit to the atmosphere.

ACID CIRCULATION TANK:

The oleum formed in the inter absorption tower and final absorption tower is

goes in the acid circulation tank. Water is added in this tank to the oleum and

the required concentration of acid is achieved. The concentration of acid in the

Tank is about to 98.5 %.this tank contain a centrifugal pump which pumps the

acid to the pipe cooler, drying tower, and absorption tower. The level of the

acid in the tank is 60% to the total capacity of the tank.

PIPE COOLER:

When the dissolution of the acid occur in the acid circulating tank, a lot of heat

is produced which heat the acid in this tank. We have to require a temperature

of 770C of the acid for the drying tower and the absorption towers. At this

temperature we get the maximum absorption. To cool this acid we use pipe

cooler. Hot acid From the Acid circulation tank is move through these pipes


41

and cool water is shower on these pipes. Water absorbed the heat and we get

the acid at required temperature. The overflow acid from the Acid circulation

tank is also cool to the to the 470C temperature by these pipes and this acid

moves tower the acid storage tank.

ACID STORAGE TANK:

In HPFL there are three acid storage tanks. They are constructed by the

stainless steel. The acid from the Acid circulation tank goes to this storage

tank. The capacity of these tanks is 2000 tons. One tank has a capacity of 1000

ton and other two have a capacity of 500 tons each.

PROCESS OF SAP PLANT:

First of all rock is feeded to the hopper with the help of loader. This sulphur

goes to the melting pit through the belt conveyor. In melting pit sulphur milt

due to the heat of the steam, moving in the pipes. After that this melting

sulphur goes to the filtering pit. Hear the molten sulphur is filter with the help

of leaf filers in series. This filtration occurs in the filtration chamber. After that

the filtered molten sulphur moves to the storage tank. From the storage tank

the molten sulphur goes to the sulphur combustion chamber through the gear

pump and the sulphur gun. Dry air from the drying chamber is also provideng

to the sulphur combustion chamber. In sulphur combustion chamber sulphur

burn in the presence of the air. The sulphur is converted in to the SO2 gas.as

S8(s) + 8 O2(g)

8 SO2(g)

In this reaction very large amount of heat is produce. This hot gas is used in the

boiler to produce the steam. Gas is passes through the tubes and water from


42

the shell of the tube fire boiler. After cooling the gas, this gas goes to the

convertor .Steam produced is stored in the steam chamber and used in the

melting of the sulphur.

In four bed convertor this gas goes to the 1st bed. There SO2 gas reacts to the

oxygen to form the SO3 gas with the help of V2O5 catalyst. The whole reaction is

given below:

1. Oxidation of SO2 into SO3 by V5+:

2 SO2 + 4V5+ + 2 O2- → 2 SO3 + 4V4+

2. Oxidation of V4+ back into V5+ by oxygen (catalyst

regeneration):

4 V4+ + O2 → 4 V5+ + 2 O2-

After this reaction again a lot of the energy is produce and this gas is then

passing through the waste heat boiler to cool this gas. After the cooling of this

gas, again this gas introduce in to the 2nd bed. There non-reactive SO2 gas

reacts with the oxygen to get better conversion. Again SO3 gas will be at high

temperature. This hot gas passes through the hot gas heat exchanger. After

cooling this gas this gas again introduce in to the 3rd bed. There unconverted

SO2 gas react with oxygen to form the SO3 gas. This gas again passes through

the cold gas heat exchanger. Then this gas passes through the first

economizer. There the temperature of the SO3 gas reduces by the water. In this

way we get the boiler feed water at high temperature. This cold gas pass

through the inter absorption tower. There SO3 gas is absorbed in sulphuric acid

at 77oC in the counter current flow manner. In this way we get the oleum in the

bottom of the tower. The reaction is given below:

H2SO4(l) + SO3(g) → H2S2O7(l)

The SO2 gas does not absorbed in the sulphuric acid. This gas lave from the

top of the inter absorption tower. This gas passes through the shells of the cold

and hot gas heat exchanger respectively. After getting hot this gas then

introduce in to the 4th bed of the convertor. There SO2 react to the oxygen to

form the SO3 again. This SO3 gas passes through the 2nd economizer. After


43

cooling this gas we introduce it in to the bottom of the final absorption tower.

Acid is shower from the top of the tower to absorb the SO3 gas. We get again

oleum in this tower.

The oleum formed from these two absorption tower moves tower the acid

circulating tank. There water is added in the oleum to get the sulphuric acid of

the required concentration as given below:

H2S2O7(l) + H2O(l) → 2 H2SO4(l)

When the water is added to the oleum very large amount of the heat is produce

this heat up the acid. We have to require the temperature of the acid 770C for

the absorption tower. For this process we use the pipe cooler for this purpose.

The overflow acid after cooling to 470C is store in the storage tank. The acid

for the SSP plant supply from these storage tanks.

Note that directly dissolving SO3 in water is impractical due to the

highly exothermic nature of the reaction. Acidic vapor or mists are formed

instead of a liquid.

http://en.wikipedia.org/wiki/Exothermic_reaction


44

WATER TREATMENT


45

WATER TREATMENT

Water serves a basic necessity in functioning of any plant , from cooing to

steam , from scrubbing to dilution everywhere water is the important . As it is a

cheap resource and universally available .

In a superphosphate and sulphuric acid plant water has much importance . It is

used for many purposes like production of sulphuric acid , in steam generation

, granulation of super phosphate e.t.c

But the quality of water is very concerned part as the plants are costly and the

equipment cannot be replaced easily especially when water is used in boilers

and pipes , it is a concern to check the quality of water being used .

The basic impurities in the water are of two types .

TSS ( Total Suspended Solids)

TDS ( Total Dissolved solids )

The Suspended solids can cause blockages across the pipe bends or valves at

least and specifically can be a huge hazard to the boiler tubes and shell ( if

used in shell). These solids can also cause corrosion of the pipes.

Whereas The dissolved solids can cause fouling or scaling of the equipment

through which water passes , and they can also affect the reactions , if water is

used in any dilution or chemical reaction .

The water which comes into the plant contains a small amount of suspended

solids but contains dissolved solids , but that amount can be disastrous to the

plant . This defines the need for a proper set up of the water treatment plant .

Hazara Phosphate Fertilizers has a proper water treatment plant to make the

water suitable for use in the boiler which includes simple sand filtration to the

ion exchange process for increasing purity to the maximum and removing any

type of TDS or TSS in the water .


46

RAW WATER INTAKE AND STORAGE

The underground water is pumped by two pumps which provide the water

needed for the entire plant and to make up the water lost during different

processes. This raw water is pumped into a storage . The water storage is

checked regularly for any visible impurity and is sealed to ensure nothing gets

into the storage to make it turbid. This water storage can store about 3 Cusecs

of water . When the water levels in this storage drop , the water can be made up

by the pumps .

WATER CIRCULATION

Two pumps are provided for the flow of water which is to be filtered and

treated for use in plants.

A pump is provided for fire fighting system.

Three pumps are present to pump raw water in the cooling tower.

FIRE FIGHTING AND SAFETY

A pump takes the water from the storage and it can be used whenever there is

need for fire-fighting . This does not require clean water , Instead the raw water

can be used for this purpose . It is used merely but can be operational at any

time .

SAND FILTRATION

The two pumps in which one is at stand-by are used for the transport of water

within plant . The water is passed through a filter containing gravels and sand .

When water passes through the sand , it’s turbidity is removed and greater

insoluble impurities are removed from the water .

With the passage of time the sand gravels get clogged by the impurities and

donot give that much cleaning . In that case the stand-by filter is used , and the

previous filter is made up by passing water in the reverse direction with

pressure , This make the gravel setup to be disturbed and the impurities flow

away with the water . This water is drained out , which takes the impurities with

itself . In this way the filter is again ready for use .

Sand filter is a cheap method and it removes most of the particles like pieces of

wood , any metal particles or other particles.


47

ION EXCHANGE TREATMENT

The water which was previously removed by the Suspended solids is now

passed through resins which remove the Dissolved Impurities. The impurities

may contain the dissolved solid either comprising of Anionic salts or Cationic

salts . This makes the necessity of Two types of Resins .

The water is passed through two towers containing

Cation Exchange Resins

Anion Exchange Resins

CATION EXCHANGE

The cation exchange resins remove cations like calcium , magnesium ,

aluminium e.t.c . There is a bed of resins through which raw water is passed .

The raw water looses the soluble cations and it moves to the anion echange

resin .

When the cation resin doesnot give much purity or is used up , then it is

regenerated by the following procedure .

Slow Rinsing : HCl soln is passed though the cationic resin @ 150 L

/ 30 min .

The concentration of HCl used is 30% .

Fast Rinsing : Raw water is pumped from top to bottom at a

pressure of about 7-8 bar . This regenerates our cationic Resin .


48

ANION EXCHANGE

The Anion exchange resins remove the anions such as sulphates , bi-

carbonates , nitrates and sulphates and instead give hydroxyl ions. In this plant

Strongly Basic anion resin is used .

When the anion exchange resin does not give that much output , then it needs

make up of resin . This is done by following procedure :-

Slow Rinsing : NaOH soln is used for slow rinsing through

anionic resin @ 66 L / hr . The concentration of NaOH soln is

07% .

Fast Rising : Water from cationic tower is pumped from upward

to bottom at a pressure of about 7 bar .

In this way the anion exchange apparatus is ready for use again .

After passing through the ion exchange resins , The amount of TSS is zero and

the amount of TDS is minimum or zero if the resins are newly regenerated .

This ensures the safety factor for the boiler , pipes and the apparatus which is

being used in the Sulphuric acid plant . There is very rare chance that the water

carries with it sulphates or carbonates which will cause scaling on the inside of

boiler tubes or steam jackets.


49

COOLING TOWER

The water which comes back to the storage from the sulphuric acid plant and

SSP plant has gained a lot of heat and it needs to be cooled before storage . So

this water is pumped to the top of a cooling tower from where it is showered

down , while keeping a constant forced flow of air upwards which further cools

the water . In this way water and air exchange maximum heat and the water .

The temperature difference is about 11 oC. Hence the water can now be easily

stored for further use .

The storage beside the cooling tower stores this water .

Now if this water has got some acidity or basicity , it can be neutralized by

adding HCl or NaOH solution to maintain the pH of water to about 8. This is

safe value , because the materials can handle some basicity , but a small acidity

in the water can be a problem for the steel structures .


50

SAFETY

HPFL ensures safe work environment by providing safety training to all

personnel on plant. As per the company policy all news personnel on plant

receive safety training prior taking charge of their responsibilities.

The training comprised of:

Importance of Safety at Plant

Use of Personal Protective Equipment

Use of Fire Extinguishers

IMPORTANCE OF SAFETY AT PLANT:

Safety plays a very important role in the production of the plant . As any

emergency in the plant can cause a shutdown , due to which the annual

production will decrease , which will cause a loss to the company as well as the

land.

USE OF PERSONAL PROTECTIVE EQUIPMENT

The safety equipment are more needed as individuals health depends on them.

A person may loose his eyes by an acid leakage .Similarly respirators should be

used in the warehouse as there is HF gas present there.


51

FIRE FIGHTING

Fire is man’s best friend and worst enemy. Fire Safety, at its most basic, is

based upon the principle of keeping fuel sources and ignition sources separate.

Three things must be present at the same time to produce fire, removal of any

of which results in extinguishment:

1. Enough oxygen to sustain combustion

2. Enough heat to reach ignition temperature

3. Some fuel or combustible material together, they produce the chemical

reaction that is fire .

USE OF FIRE EXTINGUISHERS

Fire is the most common form of disaster for any industry but could be dealt, if

well prepared. Fire erupts due to unsafe work, and could be avoided if well

planned and followed. In order to avoid any unpleasant accident, personnel are

trained for firefighting. Internees were told taught to use the fire

extinguishersfor self-safety. Strategies in fire incidents and emergency

response have beenboth notified and published by Safety Section.Using fire

extinguisher was introduced synonymously with an acronym PASS; pull, aim,

squeeze and sweep side by side.


52

ANALYSIS LAB

Following tests are performed in the lab to ensure the quality standards of the

company.

Phosphate Rock Test

ROP Test

ROP Test after curing

SSP Product Test

Sulphur Test

Water hardness Test

Water pH Test

SO2 gas Test

SO3 gas Test

Sulphuric Acid Test

Documents

Internship Report HPFL 2012