internship report-ansa aman

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| COMSATS INSTITUTE OF INFORMATION TECHNOLOGY LAHORE | July 29, 2015 INTERNSHIP REPORT SUBMITTED TO: Mr. TAUFIQ CHEEMA Technical Manager Mr. ASIM QAISER Development Manager SUBMITTED BY: Ansa Aman Ullah DURATION: 4 Weeks DEPARTMENT: Technical COMPANY NAME: ICI SODA ASH BUSINESS KHEWRA

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Page 1: Internship Report-Ansa Aman

| COMSATS INSTITUTE OF INFORMATION TECHNOLOGY LAHORE | July 29, 2015

INTERNSHIP REPORT

SUBMITTED TO:

Mr. TAUFIQ CHEEMA Technical Manager

Mr. ASIM QAISER Development Manager

SUBMITTED BY: Ansa Aman Ullah

DURATION: 4 Weeks

DEPARTMENT: Technical

COMPANY NAME: ICI SODA ASH BUSINESS KHEWRA

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Contents 1. INTRODUCTION ............................................................................................................................ 2

2. PROCESS CHEMISTRY .................................................................................................................... 3

3. PROCESS DESCRIPTION ................................................................................................................ 3

PFD: Soda Ash..................................................................................................................................................4

4. WEEKLY PROGRESS ....................................................................................................................... 5

4.1 1st WEEK-PROGRESS ........................................................................................................................ 6

Process flow of Soda Ash manufacture from the white book. ..................................................................... 6

Failure scenarios for Solid-Fluid Separators & Process Handling Equipment ............................................ 6

Steam Turbine Technology .......................................................................................................................... 6

Centrifugal Pumps. ....................................................................................................................................... 7

4.2 2nd WEEK-PROGRESS ....................................................................................................................... 7

Cooling Tower Basics and Common Misconceptions. ................................................................................. 7

Pressure Design of Straight Pipes. ............................................................................................................... 8

Project Phases & Management .................................................................................................................... 9

4.3 3rd WEEK-PROGRESS ....................................................................................................................... 9

Boiler Basics ................................................................................................................................................. 9

Water-Tube boilers ..................................................................................................................................... 10

Boiler Rating and Efficiency........................................................................................................................ 10

Pressurized Deaerators ............................................................................................................................... 11

4.4 4th WEEK-PROGRESS ....................................................................................................................... 11

Manual Valves and Valve selection. ............................................................................................................ 11

Types of Steam Flowmeters. ........................................................................................................................ 12

Basic Control Theory and Modes of Control. .............................................................................................. 13

Understanding Pump Performance Curves. ................................................................................................ 13

5. CONCLUSION & RECOMMENDATIONS ...................................................................................... 14

6. REFERENCES ................................................................................................................................. 15

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1. INTRODUCTION

ICI Pakistan Ltd. Soda ash business manufactures soda ash (sodium carbonate) by a commercially

known Solvay process. It is located in Khewra in the north part of the Punjab. The plant is situated in

an area where the two main raw materials namely limestone and salt are abundant. It is easily

accessible via road. Railway track also passes through Khewra. There is an airstrip at the worksite for

chartered flights to Lahore.

Two grades of chemically identical soda ash are produced one is the light ash (LA) and the other one

is dense ash (DA), with the only difference in their densities, 500g/l and 950g/l respectively.

The plant has a total production of 350KTPA LA and 84KTPA DA. 80% of ICI’s DA product falls in

the range of 16 Mesh to 120 Mesh. DA is mainly used in glass industry. ICI Soda Works also

manufactures 26KTPA Refined Sodium Bicarbonate (RSB). ICI Soda Works divided its whole

production in two main plant namely Plant A and Plant B with a total production of ? each respectively.

The total electrical requirement of the plant is 230KWatts/ton of Ash, out of which 180KW is self-

generated and while 50KW is supplied by WAPDA. Four steam turbines are utilized for self-generated

electricity and in case of a power cut from WAPDA two backup diesel engines are also available.

Sodium silicate, caustic, bicarbonate, steel, soap, pulp & paper, textile, water softeners, laundry &

many others consumes soda ash in one form or the other.

The company provides employment to the people of Khewra and its surrounding community. Workers

are provided with accommodation, health and education facilities since company has residential

colony, hospital and a secondary school within work premises. Hospital and school is rendering its

facilities to the surrounding community as well.

ICI Soda Ash Business has a department for its safety and security policy named as “Health, Safety,

Environment and Security” (HSE & S) as the company is well aware of its importance to hold a license

to operate. Their safety policies is based on believe and commitment. Almost 95 procedures are

mentioned in the Blue Book regarding safety. HSE &S includes Safety improvement Team (SIT),

Work To Permit (WTP), Environmental impact Assessment (EIA), Training Need Analysis (TNA),

Emergency Response Squad (22 membered,510 fire extinguishers), proper Auditing system and a

Learning-Event Database in its procedural working and setup. All these collectively rendered more

safe and secure environment for the company occupational as well as managerial works. Learning-

Event Database is provided with 24 categories of safety. M-form services are also incorporated for

any modification on plant site.

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2. PROCESS CHEMISTRY

The basic chemistry of the process is quite simple and is described by following reaction:

2NaCl + CaCO3 → Na2CO3 + CaCl2

However industrially it is complex enough to get the two ions of salt and two of limestone to change

places producing sodium carbonate and cannot be done directly, therefore ammonia is introduced as a

carrier for carbon dioxide. Therefore it is also known as Ammonia Soda Process.

3. PROCESS DESCRIPTION

To carry out the process ICI makes use of following raw materials:

Raw materials for Soda Ash manufacturing, 2015

Raw Materials PTA Source

Salt 1.66 tes PMDC, ICI Old Mines

Limestone 1.28 tes Tobar

Ammonia 4-4.5 kg Daood Hercules, Pak

American Fertilizers

Fuel 13.5 MMBTU SNGPL(natural gas),

PARCO(furnace oil),

Local & Imported coal

Water 8.5 m3 Waatli

Source: ICI Soda Ash Works

Following are the main section incorporated in the process:

1. Brine Basins

2. Kiln

3. Absorbers

4. Mono Carbonating Towers (MCT)

5. Solvay Carbonating Towers (CT)

6. Rotary filters

7. Distillation columns

8. Calciner

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In addition the process flow of the plant is briefly illustrated through PFD given below:

PFD: Soda Ash

The brine is prepared in the brine basins from water and salt and is sent to the absorbers where

ammonia is also introduced and absorption takes place here under. In the meanwhile coke along with

the lime in a preset ratio of 76kg/ton of limestone is introduced in the kilns where coke is burnt giving

off carbondioxide (CO2), which is sent to absorption section, liberating heat utilized in decomposition

of limestone to lime (CaO).This lime is then sent to the dissolver along with the water for milk of lime

(MOL).The sieved MOL is stored in the prelimers prior to pumping across distillation columns.

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Meanwhile, the ammoniated brine obtained from the absorption tower known as vat or green liquor

after cooling is pumped into the top of a series of towers called Mono-Carbonating Towers and Solvay

Towers. The purpose of Mono-Carbonating Tower is to partially carbonate ammoniated brine so that

NH3 absorbed in the brine is converted to ammonium carbonate (NH4)2CO3 while the main

carbonation occurs in Solvay Towers whereby carbondioxide gas is introduced for this purpose at

operating conditions of ?. A magma is produced, which comprises sodium bicarbonate (NaHCO3) in

crystal form which is washed through water in rotary filters, and ammonium chloride (NH4Cl) in

solution. There is liberation of a considerable amount of heat during carbonation which is removed by

water-cooled tubes at the bottom of the towers. The damp sodium bicarbonate is then fed into the large

rotary driers or calciners where heat through steam decomposes the sodium bicarbonate to give the

product with the evolution of strong CO2 and water. The carbondioxide gas is cooled, washed and

added to the gas from the kilns for reabsorption in the Solvay Towers. In addition, the NH4Cl solution

(spent process liquor) from Solvay Towers is sent to the distillation columns where ammonia is

recovered for reabsorption into brine. In the upper half of column the free ammonia is liberated by

heat through steam provided at the bottom of distillation columns and in the lower half the fixed

ammonia is liberated from Milk of Lime (MOL). Moreover, in order to economize on the use of steam

the feeder liquor is preheated in a column called the Caisse Cooler where heat exchange takes place

with outgoing gases.

There is a Dense Ash plant too for converting a part of the light ash produced to a product which is

twice as dense compared to light ash. Light soda ash is mixed with Soda Liquor in closely controlled

conditions to form monohydrate crystals, which are then dehydrated in a fluidized bed to give the

desired product:

Na2CO3 + H2O → NA2CO3.H2O + Heat (Sod. Carbonate Monohydrate)

Na2CO3.H2O + Heat → Na2CO3 + Heat (Dense Ash)

4. WEEKLY PROGRESS

During the internship learning based tasks were assigned as a scheduled activity along with few visits

to field area.

First two days specifically devoted to safety classes in which the basic and very essential learnings

were delivered of their safety, health, environment and security policy. A brief introduction was given

about the ICI’s well equipped and trained SHE department, which includes the working of their

Learning-Event Database, Blue Book procedures.

From the 3rd day to onward, internship continued under the supervision of technical department. The

whole process was studied.

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4.1 1st WEEK-PROGRESS In the 1st week following sections were covered:

Process flow of Soda Ash manufacture from the white book.

Failure scenarios for Solid-Fluid Separators & Process Handling Equipment In this section, potential failure mechanisms and their design alternatives for reducing the risks

associated with such failures for solid fluid separators and solid handling and processing equipment

and were discussed. Most frequently used solid-fluid separators are the centrifuges, filters, dust-

collectors, cyclones & electrostatic precipitators. Ignition of flammable vapors in centrifuges by static

electricity, mechanical damages caused by friction, relief valve plugging in filters, dust deflagration

due to electrostatic spark discharge or glowing particles from the upstream equipment, fluid leakages

resulting from catastrophic bearing failure, mechanical failures and spills and leakages of flammable

or toxic liquids due to gasket failure are some of the common scenarios, all dictated by over-pressures,

high temperatures and loss of containments in one way or the other.

Their potential design solutions can be implemented inherently by modification or alteration in their

design scenarios on passive efforts also on active and procedural basis, when once encountered on

operation, through control actions on spot. Some of them includes permanent bounding and grounding,

using inert atmospheres, automatic deflagration and fire suppression system, emergency relief devices,

water deluge system, conveying solids as pellets instead of granules or powder and use of

nonflammable solvents.

Steam Turbine Technology Steam turbines are one of the most versatile and oldest prime mover technologies still in general

production used to drive a generator or mechanical machinery. Unlike gas turbine and reciprocating

engine CHP systems where heat is a byproduct of power generation, steam turbines normally generate

electricity as a byproduct of heat (steam) generation. A steam turbine is captive to a separate heat

source and does not directly convert fuel to electrical energy. The energy is transferred from the boiler

to the turbine through high pressure steam that in turn power the turbine and generator. This enables

steam turbine to operate with an enormous variety of fuels. These are commonly industrially found in

paper mills, chemical plants, food industry (sugar mills) and commercially in district heating systems.

The process thermodynamics is based on Rankine cycle and can have variations according to the

particular need and application including condensing, non-condensing (back-pressure), extraction and

admission turbines. They are more rugged and with operational life often exceeding 50 years. Their

performance and efficiency enhancement can be incorporated through high pressures, steam reheat

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and combustion air preheating (from the boiler exhaust gas stream heat recovery) in large industrial

systems.

Centrifugal Pumps. Centrifugal pumps have great application in the industry, with purpose of pumping fluid and imparting

energy for various needs. In addition to its basics various calculations and technical understanding

were performed including the head-versus pressure calculations, effect of specific gravity of fluid on

pumping, net positive suction head requirements, concepts related to gauge and absolute pressures,

suction lift and head, discharge head and total head and how all these parameters play a part in proper

operation of a pump were studied and discussed. Moreover, API for centrifugal pumps were also apart

of technical understandings.

To be well known to this equipment, a field trip was also organized under the supervision of Mr. Yasir

Akram where centrifugal pumps installed at various locations on the site were examined and their

operational technicalities discussed.

4.2 2nd WEEK-PROGRESS

Sections covered during 2nd week:

Cooling Tower Basics and Common Misconceptions. Cooling Tower is a simple equipment in comparison to most of the industrial equipments. The basic

principle of this device is that of evaporation condensation and exchange of sensible heat, itself it is

neither a heat source nor a heat sink. The capability of a cooling tower is a measure of how close the

tower can bring the water temperature to the wet-bulb temperature (WBT) of the entering air which is

basically the Approach of a cooling tower. The lower the WBT, which indicates either cool air, low

humidity or a combination of two, the lower the cooling tower can cool the water. Any approach less

than 5 °F is not customary in the industry. Moreover performance of a cooling tower is defined by

following five parameters:

1- Hot-water temperature (HWT), 2-Cold-Water temperature (CWT), 3-Wet-Bulb temperature

(WBT), 4-Water Flowrate (L), 5-Air Flowrate (G).

One misconception prevails regarding range of a cooling tower but it is to be known that the range

is completely independent of a cooling tower characteristics so it would be inappropriate to mention

that the tower is cooling the water let say 20°.Infact the measure of actual thermal capability of a

cooling tower is not the total amount of heat rejected rather it is the level at which this heat is rejected.

Moreover as the concept of Approach is concerned, with the fall in the WBT, CWT also goes down

but not in a one-to-one relationship i-e: for each 2°F drop in WBT the CWT will drop approximately

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1°F.Therefore, it might be possible that the approach of a cooling tower may differ from the designed

with changing weather conditions or more specifically the WBT.

In addition to these technical concepts, a problematic scenario was also assigned where on given

operating conditions heat load and makeup water were to be evaluated. It was done making use of the

following parameters and equations:

Approach (Two - Ta, wi) Temperature difference between the temperature of the condenser water

leaving the tower and the wet bulb temperature of air entering the tower.

Range (Twi - Two) Temperature difference between the temperature of condenser water entering the

tower and the temperature leaving the cooling tower.

Effectiveness of Cooling Tower = Range

Approach + Rangex10

Blowdown: Water discharged to the drain periodically to avoid buildup of dissolved solids. The

Blowdown is 0.9 % of total circulating water flow.

Drift loss: Water droplets that are carried out of the cooling tower with the exhaust air. Drift droplets

have the same concentration of impurities as the water entering the tower. It is about 0.1 % of

circulating water.

Makeup (0.9%BD+0.1%DL+1.2%EL): Water added to the circulating water to compensate for the

loss of water to evaporation, drift, and blowdown. Evaporation losses are 1-1.2% of circulating water.

Heat-Load [Btu/hr.]=500 x water flowrate [GPM] x Range [°F]

The cooling tower on the work site were also visited to have a sound grip on the design of a tower

where there was a counter-current flow of induced cooling tower design.

Pressure Design of Straight Pipes. Pipe thicknesses varies with the varying duty of design pressures therefore it is necessary to size a pipe

with a thickness to bear the pressure conditions with mechanical, erosion and corrosion allowances

known as minimum thickness required for a selected pipe (tm). It is given by:

tm=t + c

Where c is the sum of mechanical allowances (thread or groove depth) plus corrosion and erosion

allowances, and ‘t’ is the design pressure thickness, as calculated (for internal pressures):

t=PD/2(SE+PY)

All values for these parameter can be extracted from the relevant literature. Here the main objective

was to get use to the step by step calculations and how to proceed and go through various phases for

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one required parameter. This adds a basis to design scenarios that will surely be encountered in the

near future.

Project Phases & Management Project scheduling and understanding/handling risk is crucial to success in science and engineering.

Project management is the art of matching a project goals, tasks. And resources to accomplish a goal

as needed that is within limited time, money and resources. It is more like to do the right thing with

the right tools in a right way.

While project is more like a process, it has a beginning and an end with various sequential phases. A

phase represents a grouping of similar activities that has a very loosely defined beginning and end.

Project lifecycle has four major phases namely initiation, planning, execution and project close-out.

The initiation involves:

1. Defining the goals of the project (document that list goals with short success defining

statement).

2. Defining project tasks/activities for set goals.

3. Determining and verifying resource requirements (time, money, people, space, equipment etc.)

4. Identifying risks and develop mitigation (backup) plans.

Planning holds:

Development of a complete schedule involving a giant chart which plots the tasks, people responsible

for these tasks, and a timeline. It also includes detailed staffing, procurement and project controls plans.

Whereas the execution phase is all about carrying out all these tasks and activities which are being

scheduled and plan for the accomplishment of the desired goals. During this phase a good

co0ordination among the members and a sound grip on documentation, modifications and reviews of

schedule and status are on keynote for the completion of a project.

And at last the close-out phase being after the goals have achieved, for revisions and improvements in

the future projects. Basically the performance of the project team is evaluated in this phase.

4.3 3rd WEEK-PROGRESS 3rd week was engaged in tasks related to boilers:

Boiler Basics A phase change occur in a boiler from liquid to steam by heating process. Mainly there are two types

of boilers, water tube boilers and fire tube boilers. Blowdown is carried to control the TDS of the

boiler water within the recommended limits. Make-up water is feed to compensate for losses due to

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steam generation and blowdown. Fire tube boilers generate saturated steam as heat is within tubes

surrounded by water to boil while the water tube boilers generate superheated steam where the water

is within tubes surrounded by heat for boiling/steam generation. Soft & BFW total hardness, dissolved

oxygen in BFW, return condensate pH, boiler water pH and TDS, Boiler water caustic alkalinity,

oxygen scavenger reserves and scale inhibitor reserves are some of the important operating parameter

for boiler systems.

Boiler water treatment is therefore necessary for proper operation where scale inhibitors, neutralizing

amines and oxygen scavengers are typically used to control parameters affecting the efficiency and

working of boiler systems.

Water-Tube boilers Many of these operate on principle of natural water circulation (thermosiphoning). Cooler water is fed

into the steam drum behind a baffle where, because the density of the cold water is greater, it descends

in the downcomer towards the lower or mud drum, displacing the warmer water up into the front tubes

and the cycle continues. Heat is absorbed by radiant mode through furnace section lining (finned tubes),

and from hot flue gases by conduction and convection.

Economizer and super heater are the two main parts of a water tube boiler. Economizer is a heat

exchanger through which the feed water is pumped and this heat is taken off from the flue gases which

after passing through the boiler still hot enough to be used for improving the efficiency of a boiler. In

broad terms a 10°C increase in the feed water will give an efficiency improvement of 2%.

Super heater is also a heat exchanger where additional heat is added to the saturated steam to get

converted to the superheated steam. In water tube boilers it may be the additional pendant suspended

in the furnace area where the hot gases will provide the degree of superheat required.

Boiler Rating and Efficiency There are three types of boiler rating commonly used:

‘From and at’ rating: the amount of steam in kg/h which the boiler can create ‘from and at

100°C’, at atmospheric pressure.

kW rating: Steam output (kg/h)=Boiler rating (kW) x [(36oos/h)/energy to be added (kJ/kg)].

It is not an evaporation rate but subject to the same ‘From and at’ factor.

Boiler horsepower (BoHP): Amount of energy required to evaporate 34lb of water at 212°F

atmospheric conditions. This unit tends to be used only in USA and Australia.

Boiler efficiency is simply relating the energy output to the energy input:

Boiler Efficiency (%) =Heat exported in steam/Heat provided by fuel x 100

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Where heat exported in steam is calculated through knowledge of feed water temperature, pressure at

which the steam is exported and the steam flowrate from steam tables.

To get in detail, few technical problems related to the boilers rating, efficiency and steam requirement

were done. All these helped to grasp more conveniently the boiler needs, how to keep it on safe side

of operation and get the maximum of it in an efficient way.

Pressurized Deaerators Deaeration is an important pretreatment phase for the boiler feed water where the gases need to be

removed since oxygen is the main cause of corrosion in the boilers and CO2 presence also lower the

pH thus the water tend to be more acidic and the rate of corrosion increases. Moreover the essential

requirements to reduce the corrosion is to maintain the pH around 8.5-9, the lowest level at which the

CO2 is absent.

Operating principle: if a liquid is at saturation temperature, the solubility of a gas in it is zero.

The first step for treatment is to heat the water since the higher the temperature, the lower will be the

oxygen content. However, high temperature operation at atmospheric pressure can be difficult due to

the close proximity of the saturation temperature and the probability of cavitation in the feed pump.

Therefore oxygen scavengers (sodium sulphite, hydrazine or tannin) are used for further removal.

But the cases exist where plant due to their size, special application or local standards will need to

either reduce or increase the amount of chemicals used. For such plants it is common practice to use a

pressurized Deaerators.

These are mainly used for high pressure water tube boilers and steam plant handling superheated steam

where it is vital to keep the oxygen level less than 7bbp through pressurized Deaerators since the rate

of attack rapidly at higher temperatures due to dissolved gases.

Calculations were also made for the energy input (steam) requirements for Deaeration of a typical

boiler feed water.

4.4 4th WEEK-PROGRESS

In the last week, Process control and instrumentation relevant tasks were assigned:

Manual Valves and Valve selection. Major function of a valve in fluid handling systems includes stopping and starting the flow, controlling

flowrate and diverting flow. There is also a grouping of valves by the method of flow regulation:

Closing-down valves (globe and piston), sliding valves (gate valves), rotary valves (plug, ball,

butterfly) and flex body valves (pinch, diaphragm).

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Valves for stopping and starting flow are normally selected for low resistance and straight-through

flow passages, these are usually sliding, rotary and flex body valves. Valves for controlling the

flowrate are typically closing down valves because of the directly proportional relationship b/w the

size of the seat opening and the travel of the closure member. Rotary and flex body may also be used

but only over a restricted valve-opening range. Valves for diverting flow have three or more ports

depending on the duty and are plug valves and ball valves.

Valves for fluids carrying solids in suspension must have a closure member that slides across the seat

with a wiping motion. Valves are provided with many types of end-connections, most important are

threaded, flanged and welding end-connections.

All these various valves types and their end-connection were observed at various locations at visit to

plant site under the supervision of Mr.Tanveer. During this visit, an introductory round to ICI

laboratory machinery and usage was also made. It was a good piece of knowledge earned that how the

analysis of all the raw materials and products were made prior to any big decision for their

specification and quality checks.

Types of Steam Flowmeters. Among various types of flowmeters following are those suitable for steam and condensate

applications:

1. Orifice plate

2. Turbine (shunt and bypass type too)

3. Variable area

4. Spring loaded variable area (SLVA)

5. Direct in-line/targeted variable area

6. Ultrasonic

7. Vortex shedding

Their installation involves the pressure tapping positioning as well as factors related to the pipe-work

must be keen to known includes the minimum of downstream straight pipe dia and upstream straight

pipe dia where the latter is affected by the discharge co-efficient of the flowmeter [β=d(flowmeter

dia)/D (pipe dia)], nature and geometry of the preceding obstruction.

Orifices are used anywhere the flowrate remains within the limited turndown ratio of 4:1 to 5:1, this

may include the boiler house. Turbine flowmeters, with turndown ratio of 25:1, are for liquids,

condensates and insertion type of these may include the applications for steam (saturated

&superheated) and gas/air as well. Rota-meters with turndown ratio 10:1 are for metering of gases,

small air-flow metering, and lab applications. These are sometime used as flow indicating devices

rather than flow-metering. Whereas SLVA with high turndown ratio 100:1 are for boiler house and

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large plant applications. Ultrasonic are best suited for corrosive liquids as well as has typical

application in monitoring the fluids such as measuring condensate return. They can also be used for

energy monitoring. While the vortex shedding finds its application in direct steam measurements at

both boiler and point of use locations, also in natural gas measurements for boiler fuel flow.

Basic Control Theory and Modes of Control. Control of a process is the most crucial factor in performance and success of a safe and efficient plant

operation, therefore it is always necessary to have complete control over the plant in order to get the

required output. A typical control system may consist of a sensing element, measuring device,

transmitter, controller and the final control element which of most cases are valves.

There are two basic modes of control:

Two step/Two position (On/off)-the valve is either fully open or fully closed, with no

intermediate state. These are simple and very low cost.

Continuous (modulating)-the valve can move between fully open or fully closed, or may held

at any intermediate position.

There are three basic control actions that are often applied to continuous control:

5. Proportional (P) action with adjustable gain to obtain stability.

6. Integral (I) action to compensate for offset due to load changes.

7. Derivative (D) action to speed up valve movement when rapid load changes take place.

Depending on the control requirement, following characteristic features help in selection of a more

appropriate duty:

Controller Response time Overshoot Error

Proportional Small Large Small

Integral Decreases Increases Zero

Derivative Increases Decreases Small change

Understanding Pump Performance Curves. Pump performance curves are just like the control panel of the pumps. All operators, engineers,

mechanics, and anyone involved with the pumps should understand the curve and its elements, and

how the relate. The performance curve indicates that the pump will discharge a certain volume or flow

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(gpm) of a liquid, at a certain pressure or head (H), at an indicated velocity or speed, while consuming

a specific quantity of horsepower (HP).

Performance curve of a pump includes the following four curves on a common graph:

The Head-Flow Curve (H-Q Curve)

The Efficiency Curve

The Energy Curve (records Brake Horsepower-BHP)

The Pump’s minimum Requirement Curve (NPSHr curve)

With the curve, we can take the differential pressure gauge readings on the pump and understand them.

We can use these readings to determine if the pump is operating at, away (to the left or right) from its

best efficiency zone and determine if the pump is functioning adequately. We can even visualize the

maintenance required for the pump based on its curve location, and visualize the corrective procedures

to resolve the maintenance.

With all these technical facilities provided by these curves, it was quite good to learn about a pump

performance by knowing how to make best use of these curve and in practice how to evaluate these

parameters from the curves. That will be pretty good in the future works.

5. CONCLUSION & RECOMMENDATIONS

ICI Soda Ash Business is no doubt an emerging industry for young engineers to avail the opportunities

for their professional skills and experiences from interns to trainees and joining as an engineer to

impart their roles in the industrial sector. The environment here is friendly and co-operative. On

completion of my internship I have grasped valuable information relating working environment, time

and work management in addition to my engineering or more specifically technical knowledge. As a

fresh engineer one must know the various equipment used in industries with the best knowledge of

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how to operate them efficiently, therefore I have learned it during my internship which will definitely

add value to my career projects in future.

For conducting internships over here, Company and the concerned departments besides being enough

co-operative and responsible for their interns intellectual empowerment though if indulge their little

consideration towards more strategic, well organized and planned setup to share their experiences

among them will hopefully help in a good repute of company in the social as well as industrial sector.

So there might be a common room where combined meetings and sessions of these interns held where

they can share their routine activities and knowledge and where the supervisors and other experienced

personnel from the company rendered their precious time to impart fruitful information to the interns.

6. REFERENCES

1. Shahab Mufti, Technical Department. SODA ASH MANUFACTURING PROCESS AT

KHEWRA.2nd edition. ICI Pakistan Ltd Khewra.

2. Cooling Tower Basic and Common Misconceptions. Jalal Engineering, [email protected].

Page No. 1-6. [Accessed July 10, 2015]

3. http:/www.spiraxsarco.com/Resources/Pages/Steam.Engineering-Tutorials/the boiler

house/water-tube boilers.aspx. Page No. 1-6 [Accessed July 15, 2015]

4. Muhammad Hyder Raza, Sales Engineer. Presentation: Boiler Inspection & Boiler

Efficiency. ONDEO Nalco Gulf Ltd. [Accessed July 15, 2015]

5. http:/www.spiraxsarco.com/Resources/Pages/Steam.Engineering-Tutorials/the boiler

house/Boiler Ratings.aspx. Page No. 1-3 [Accessed July 16, 2015]

6. http:/www.spiraxsarco.com/Resources/Pages/Steam.Engineering-Tutorials/the boiler

house/Boiler Efficiency and Combustion.aspx. [Accessed July 16, 2015]

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house/Pressurized Deaerators.aspx. Page No. 1-9 [Accessed July 16, 2015]

8. http:/www.spiraxsarco.com/Resources/Pages/Steam.Engineering-

Tutorials/flowmetering/types-of-steam-flowmeter.aspx. Page No. 1-18 [Accessed July 24,

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theory/basic-control-theory.aspx. Page No. 1-15 [Accessed July 24, 2015]

10. Steam Tables. ASME Steam Tables 1967 by The American Society of Mechanical Engineers.

11. Pilot API: Centrifugal Pumps.