WOLDIYA UNIVERSITY

WOLDIYA UNIVERSITY INSTITUTE OF TECHNOLOGY

CHEMICAL ENGINEERING DEPARTMENT

FINAL INDUSTRIAL ATTACHMENT REPORT

HOSTING COMPANY: ETAP SOAP FACTORY
By:
MILLION FIREWU
ID No. (Tech: WDU112163/11)

Academic Advisor: Mr. Sisay Wondimagegn

Company Advisor: Mr. Deribe Getachew

November, 2022
DECLARATION
I hereby, declare this final internship report is the results of my work except as cited in the
reference; and compiled according to the internship report guideline given.

Name of the student: MILLION FIREWU Signature: _______ Date: __________

This final internship report has been submitted for examination with my approval as
University advisor.

Advisor Name : Mr. Sisay Wondmagegn Signature: _______ Date: __________

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EXECUTIVE SUMMARY
This final internship report explains what I have understood in my stay in ETAB soap factory
for about three months. In my stay in this company, I have tried to understand the basic
processes that are taking place for the production of soap (starting from raw materials
preparation to the final products). The report covers about eight major contents starting from
the introduction part up to the recommendations. The introduction contains the company’s
background, its management organization, its objective and limitation of the company that
face me while I am performing my task. The second portion (literature review) covers the
general or basic theories of the processing of soap product. The third portion is the
manufacturing process of soap in the ETAB soap factory. The finishing process is used to
modify the quality of the soap by adding different ingredients. This section includes mixing,
milling, ploddering, molding, stamping, cutting and packaging. During the production
process, quality controlling and assurance is necessary to control the quality parameters of the
raw materials, the intermediate product and the end product. This final report also contains
the case study taken on selected problem, overall benefits of the internship program,
conclusion and the recommendations that are useful to solve them.

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ACKNOWLEDGMENT
Above all, to the great almighty God, the author of knowledge and wisdom, for his countless
love.
The completion of this internship report could not have been possible without the
participation and assistance of so many people whose name may not all be enumerated. Their
contribution is sincerely appreciated and gratefully acknowledged. However, I would like to
express my deep appreciation and indebtedness particularly to the following:
Mr. Deribe Getachew my company advisor, Mr. Sisay Wondmagegn my academic advisor,
all quality control and assurance lab chemists and factory workers for their endless support,
kind and understanding during my stay.
I would like to give my deepest respect and appreciation to all of chemical engineering
department instructors, for their support and inspiration that in a process of changing my
theoretical session in to practical.
To all relatives, friends and others who in one way or another shared their support either
morally, financially and physically, thank you!

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Contents
DECLARATION ..................................................................................................................................... i
EXECUTIVE SUMMARY .................................................................................................................... ii
ACKNOWLEDGMENT........................................................................................................................ iii
LIST OF TABLES ................................................................................................................................. vi
LIST OF FIGURES ............................................................................................................................... vi
1. INTRODUCTION .............................................................................................................................. 1
1.1 Background of ETAB soap factory............................................................................................... 1
1.2 Management and organization structure of ETAB soap factory ................................................... 2
2. TYPES OF SOAP MANUFACTURING PROCESSES IN ETAB SOAP FACTORY ..................... 5
2.1 Batch soap production Process ..................................................................................................... 5
2.2 The Continuous soap production Process ..................................................................................... 6
2.3 Production Process of ETAB Soap Factory .................................................................................. 6
2.4 Boiler plant.................................................................................................................................... 7
2.5 Cooling tower................................................................................................................................ 8
2.6 Raw material preparation .............................................................................................................. 8
2.6.1 Receiving and storage of raw materials ................................................................................. 8
2.6.2 Sodium silicate melting ........................................................................................................ 10
2.6.3 Tallow melting ..................................................................................................................... 11
2.6.4 Bleacher of oil ...................................................................................................................... 12
2.6.5 Batch formation and oil blending process ............................................................................ 13
2.7 Soap production section .............................................................................................................. 14
2.7.1 Saponification process ......................................................................................................... 14
2.7.2 Temporary storage (feed tank) ............................................................................................. 15
2.7.3 Atomizer with Cyclone and Condenser ............................................................................... 15
2.8 Finishing processes ..................................................................................................................... 17
2.8.1 Mixers .................................................................................................................................. 17
2.8.2 Millers .................................................................................................................................. 18
2.8.3 Plodder ................................................................................................................................. 18
2.8.4 Press (stamper) ..................................................................................................................... 18
2.8.5 Cutter.................................................................................................................................... 19
2.8.6 Packaging of products .......................................................................................................... 19
2.9 Quality and operation parameters ............................................................................................... 20
2.9.1 Quality controlling and assurance parameters ..................................................................... 20
2.9.2 Operating parameters ........................................................................................................... 21

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3. PROJECT (HARD WATER TREATMENT) .................................................................................. 22

3.1 Statement of the problem ............................................................................................................ 22
3.1 Objective ..................................................................................................................................... 23
3.3 Significance of the study ............................................................................................................. 23
3.4 Scope of the study ....................................................................................................................... 23
3.5 Material and Method ................................................................................................................... 23
3.6 Result and Discussion ................................................................................................................. 24
4. CONCLUSION AND RECOMMENDATION ................................................................................ 26
4.1 CONCLUSION ........................................................................................................................... 26
4.2 RECOMMENDATION .............................................................................................................. 26
REFERENCE........................................................................................................................................ 27

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LIST OF TABLES
Table 1 Types of soap product and their batch type ............................................................................... 2
Table 2 Types of slurry and amount (recipe) of different types of oil in each slurry ........................... 13

LIST OF FIGURES
Figure 1: overall management structure of the company ....................................................................... 3
Figure 2 wood boiler ............................................................................................................................... 8
Figure 3 process flow diagram of sodium silicate melting ................................................................... 11
Figure 4 process flow diagram of tallow melting ................................................................................. 12
Figure 5 process flow diagram of oil bleaching process ....................................................................... 13
Figure 6 process flow diagram of oil melting and blending ................................................................. 14
Figure 7 Crutcher (reactor) (source: from company manual book) ...................................................... 15
Figure 8 Atomizer (soap dryer) ............................................................................................................. 16
Figure 9 cyclone.................................................................................................................................... 17
Figure 10 mixer (source: from manual book) ....................................................................................... 18
Figure 11 plodder (source: from manual book) .................................................................................... 18
Figure 12 Over all process flow diagram of soap production ............................................................... 19
Figure 16 Zeolite process water treatment flow diagram...................................................................... 25
Figure 15: Zeolite process water treatment flow diagramZeolite bed .................................................. 25

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1. INTRODUCTION
1.1 Background of ETAB soap factory
The name ETAB came from by taking the first letter of the owner name (Eskinder Tesfaye
Abebe Biru). The project for the ETAB soap factory is started by Mr. Tesfaye Abebe. He had
been producing a bar soap from tallow and caustic soda inside his house by using simple
machine. This machine has reactor, mixer, mould and cutter operated by hand. The
production process involves strenuous human efforts which require a lot of energy and time
input by the producer. Mr. Eskinder Tesfaye develops this small scale works into large scale
industrial works by installing different unit operations. Now a day ETAB soap and detergent
industry is a privatized company, its basement is started in 1993 by Mr. Eskinder Tesfaye,
using a single unit operation for the production of bar soap to a single society in Hawassa by
setting its basement in a rent house. ETAB soap factory is a factory that produce a bar soaps
having different forms, sizes and quality.

ETAB soap factory was established and legally registered in Ethiopia by the name ETAB
Soap Factory in 1997 in Hawassa Sidamma regional state as a private company. Mr.
Eskinder Tesfaye who is an auto mechanic and his father Mr. Tesfaye Abebe is a chemist.
Mr. Eskinder Tesfaye and his family established the company. The factory started its
operation with machines acquired from CHEMCO Company in Italy. In 1999, the company
had undertaken additional construction to facilitate production processes. The first expansion
had enabled it to raise its production capacity from 1tn to 1.5tn a day, increasing its
employees from 9 to 250. Now a day there are around 450 labor and skilled human power
are working responsibly in two shifts per a day because of COVID-19 and shortage of raw
material each shifts work 8 hours. Before COVID-19 it was working in three shift.

ETAB had undertaken an expansion project at a cost of 15 million Birr, which had been
doubled its production capacity per year. The expansion project had enabled the factory to
produce bathroom, laundry and toilet soap, liquid soap and others. Now a day the new
facility is able to supply approximately 15000 cartons per day, at full capacity. ETAB soap
factory currently coordinates/manages most of its operations at the facility of Hawassa city
(SRS) in an industrial zone area prepared by the regional government. The facility is situated
in a total area of 9854m2. When started, the company was producing six types of laundry
soap from 100 to 200gm. Now a day due to the use of advanced technology working with

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advanced unit operation it has been producing 30 types of soaps from ETAB (25 gm.) toilet
soap to UNHCR (245 – 250 gm.) laundry soap. These products of ETAB soap factory are
listed below in the table;

Table 1 Types of soap product and their batch type

Bach type Types of soap produced from given batch

Genuine (GN1) Walta white, Yani120g pink, Shewa white, Yani200g pink,
Yani200g white, Yani120g white, Jegol orange 140g, Jegol ivory
190g,Zumbara, infinity ,city

Hammer small, Nazrawi, Kazira, Toilet soap small pink, Toilet soap
large pink
Build (BL1)

Hawassa, Hammer large, Walta yellow Toilet soap small white,

Toilet soap large white
Build (BL2)

Filled (FL1) Kukissa, Large lion, UNICEF 75g pink, UNICEF 250g pink,

Filled (FL2) small lion, Tabor, UNHCR, Dashen

ETAB soap factory sells its products locally on both urban and rural areas of Ethiopia. It
distributes its bar soap product in many areas of Ethiopia especially in Hawassa,
Shashemenie and many rural areas of south part of Ethiopia, and sometimes it also
distributes its product to Harrer, Dire dawa, Weldia, Adama Asosa and other city.

1.2 Management and organization structure of ETAB soap factory

ESF have abroad management and organization structure which is guided by five main
departments.

The main departments of the factory are;

i. financial department
ii. Marketing department
iii. Production department
iv. Administration (human resource) department
v. Property and purchasing (Commercial) department

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General Manager

Plan Deputy General Quality control

&program Manager &assurance

Human resource Property & Production dep`t Marketing dep`t Finance dep`t
dep`t purchasing dep`t

Personal General Production Operational Cost & General

division service plan control division budget accountant

Property Purchasing Marketing Sales division

division division promotion

Figure 1: overall management structure of the company

The individual departments have their own tasks. The tasks of general manager and each department
are described below.

General Manager

 Provides necessary resources to maintain and improve the system.

 Creates appropriate internal communication process and allows the interests of customer to
be handled in appropriate manner.
 Controls overall management related tasks and manages the individual departments.
 Formulate and ensures the implementation of quality policy.
 Conduct management reviews over the whole department.
Finance department
 Ensures all purchases are properly authorized, salaried and accounted.
 Ensures audit and other statutory and regulatory compliance issues are handled
appropriately, efficiently and promptly.
Administration (human resource) department
 Define qualification of personnel and ensures recruitment of suitable qualified Staff.
 Perform general administration.
 Provide induction training to new employees.

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Quality control
 Checking the parameters of final products.
 Assure quality, develop and maintain strong brands and minimize risk.
 Test the quality parameters incoming raw material
 Control the quality of the intermediate product with in the process.
Commercial department

 Controls property related issues.

 Purchasing of different raw materials.
Production department

 Set annual and daily production plan.

 Identify the problem that affects the quality of the product.
 Eliminate waste.
 Ensure that the different unit operations are working properly to optimize the production
capacity of the company.
Marketing department
 Study current and future market and propose appropriate actions.
 Maximizes sales through use of various marketing structure.
 Measures customers.

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2. TYPES OF SOAP MANUFACTURING PROCESSES IN ETAB SOAP

FACTORY
2.1 Batch soap production Process
The batch process of making soap is still used today by small soap manufacturing
companies. ETAB soap factory is one of these companies which use batch process of soap
making. ETAB soap factory uses kettle (batch) neutralization process due to steam
hydrolysis of triglyceride. Triglycerides are also saponified in a two-step process that begins
with steam hydrolysis of the triglyceride. This process gives the fatty acid, not its salt, as
well as glycerol. Subsequently, the fatty acid is neutralized with alkali to give the soap. The
advantage of the two-step process is that the fatty acids can be purified, which leads to soaps
of improved quality. Steam hydrolysis proceeds via a mechanism similar to the base-
catalyzed route, involving the attack of water (not hydroxide) at the carbonyl center. The
process is slower, hence the requirement for steam and the general steps of batch not occur in
this factory because its batch neutralization of soap making does not use direct batch
saponification process. The steps to produce bar soap using batch processes are the
following;
Boiling: Fats and alkali are melted in a kettle, which is a steel tank that can stand three stores
high and hold several thousand pounds of material. Steam coils within the kettle heat the
batch and bring it to a boil. After boiling, the mass thickens as the fat reacts with the alkali,
producing soap and glycerin.
Salting: The soap and glycerin must now be separated. The mixture is treated with salt,
causing the soap to rise to the top and the glycerin to settle to the bottom. The glycerin is
extracted from the bottom of the kettle.
Strong change: To remove the small amounts of fat that have not saponified, a strong
caustic solution is added to the kettle. This step in the process is called strong change. The
mass is brought to boil again, and the rest of the fat turns to soap. The batch may be given
another salt treatment at this time, or the manufacturer may proceed to the next step.
Pitching: The next step is called pitching. The soap in the kettle is boiled again with added
water. The mass eventually separates into two layers. The top layer is called neat soap, which
are about 70% soap and 30% water. The lower layer, called nigre, contains most of the
impurities in the soap such as dirt and salt, as well as most of the water. The neat soap is
taken off the top. The soap is then cooled.

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2.2 The Continuous soap production Process

Continuous process of soap making are preferred because of their speed, flexibility and cost
economy. The steps to produce bar soap by continuous processes are;

Splitting: The first step of the continuous process splits natural fat into fatty acids and
glycerin. The equipment used is a vertical stainless steel column with the diameter of a barrel
called a hydrolyser. Pumps and meters attached to the column allow precise measurements
and control of the process. Molten fat is pumped into one end of the column, while at the
other end water at high temperature (130°C) and pressure is introduced. This splits the fat
into its two components. The fatty acid and glycerin are pumped out continuously as more
fat and water enter. The fatty acids are then distilled for purification.

Mixing: The purified fatty acids are then mixed with a precise amount of alkali to form
soap. Other ingredients such as abrasives and fragrance are also mixed in. The hot liquid
soap may be then whipped to incorporate air.

Cooling and finishing: The soap is then poured into molds and allowed to harden into a
large slab. And it is also allowed to be cooled in a special freezer. The slab is cut into smaller
pieces of bar size, which are then stamped and wrapped. The entire continuous process, from
splitting to finishing, can be accomplished in several hours.

Milling: Most toilet soaps undergo additional processing called milling. The milled bar
lathers up better and has a finer consistency than non-milled soap. The cooled soap is fed
through several sets of heavy rollers (mills), which crush and knead it. Perfumes should be
incorporated at this time because their volatile oils do not evaporate in the cold mixture.
After the soap emerges from the mills, it is pressed into a smooth cylinder and extruded. The
extruded soap is cut into bar size, stamped and wrapped.

2.3 Production Process of ETAB Soap Factory

Different unit operations are installed for different purpose (from raw material preparation up
to final product) in ETAB soap factory. These unit operations are sodium silicate melted,
tallow melted, bleacher, oil blending, saponification, atomizer (soap dryer), mixer, and soap
miller, plodder, moulding &stamping, cutting and packaging. Soap making or the
saponification process is done by the reaction of fatty acids and caustic alkali, the properties of
the resulting soap depending on the mixture of fats used, the kind of caustic alkali and the actual

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process employed. Saponification is the chemical process of making soap that involves an
exothermic reaction between sodium hydroxide and a fat (oils).

The alkaline metals usually used in soap making are sodium and potassium, which Produce water
soluble soaps. In ETAB soap factory produce only bar soap products that means soap
manufacture that is based on the processing of natural fat and different palms. First oil or fatty
acid from tallow and different types of palms was prepared in oil preparation room in the form of
refining and bleaching unit operations because soap produced from animal fat are less in quality.
So soaps produced in a component of animal and plant oils for the purpose high quality soap
produced. The manufacturing of bar soap passes a number of unit operations to competitive for
quality and quantity for other soap factory. So the production of this qualitative soap from raw
allows refining to bar soap product use properly.

The generation of the unit operation use steam energy and electricity. In ETAB soap factory
the only source of heat for preparation of substances in to a useful product is steam produced
from boiler but machines like mixers, belts, vacuum plodder, and cutter use electricity.
ETAB soap factory use so many unit operation for production of final quality soap product,
so the process description of each unit operation are the following;

2.4 Boiler plant

Boiler is equipment used for producing and transferring steam for the purpose of either
heating or melting of a given substance. A boiler is basically a closed vessel into which water
is heated until the water is converted into steam at required pressure.

In ETAB soap factory to use generated steam produced from boiler as source of energy for
steam energy required unit operation to satisfy their efficiency. In this factory there are two
types of unit operations are used.

 Furnace boilers
 Wood boilers

In ETAB factory previously they use all of the above two boilers but at this time use only
wood boiler. The uses of boiler types consider profitability, environmental impact and heat
transfer are the main considerations for the company. Since profitability is the main
consideration for this company, they done a cost estimation for each boiler and comparing
them resulting wood boiler is the best to get high profit. Wood boiler is a boiler that uses
wood. The basic working principle of boiler is very simple and easy to understand. The

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boiler is essentially a closed vessel inside which water is stored. Wood is burnt in the boiler
and hot gasses are produced. These hot gasses come in the pipe and the water is inside the
shell between those heats is transfer and consequently steam is produced in the boiler. Then
this steam is piped to the any unit operation.

Figure 2 wood boiler

2.5 Cooling tower

Cooling tower is a unit operation which is used to cool the processed water and recycle it. It
is operated by the application of fan. The machines that used in different section are operated
by electrical system and heat is produced while processing hence it is needed to maintain a
cooling system in the machines. It is difficult to install fan in each machine so the cooling
system is maintained by using cold water which is supplied from cooling section. The
processed water from different unit operations flows to cooling tower section to be cold.
Then the fan, which installed inside the cooling tower, ventilates the system and allows the
hot air to be released from the water. Then the cold water is recycled to be used for cooling
system.

2.6 Raw material preparation

2.6.1 Receiving and storage of raw materials

Raw materials should be handled and stored in a manner to prevent contamination and cross
contamination. Raw materials may be imported from foreign countries or locally produced.
Whatever it is written procedures should be established which describe the purchase (price),
receipt, identification (physical appearance), quarantine, storage, handling, sampling, testing
(Content of the raw material like moisture content, total fatty matter, impurity and etc), and

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approval or rejection of raw materials. Barrel is used for storage of liquids materials like
different types of oil and hydrogen per oxide. Solids like caustic soda, titanium dioxide,
dolomite, solid sodium silicate, and other additives are stored in sack. Raw materials that are
stored outdoors should be in suitable containers. Each container of raw materials should be
assigned and identified with a distinctive code, receipt number. This code is used for
recording the disposition of each receipt. Production of soap involves utilizing various oils
and fats to produce soaps with the optimum qualities for the required purposes. Selection is
usually based on quality of oil, desired product properties and current marker costs.

There are three main raw materials in bar soap making, these are; oil (blended from different
types) caustic soda and water. Other ingredients (H2O2, binders like sodium silicates,
colorants, perfumes, filler (dolomite), and other additives) are added to give the soap a
pleasant odor or color, or to improve its skin-softening qualities and to increase the weight of
final product. Most of these raw materials are locally available and some are imported.

Tallow: It is a hard, almost white fat high in long chain of fatty acids. This produces a soap
which dissolves slowly and with a thick lasting lather which is mild and has good cleaning
purposes. It is obtained by rendering beef or mutton.

Caustic soda: the use of this chemical is to neutralize the fatty acids or fats while during
soap making.

Palm fatty acids: ETAB soap factory uses two types of palm fatty acids which are
purchased from foreign markets such as Malaysia, Indonesia, and Egypt. The two types of
palms oils are palm fatty acid distillate and refined bleached distillate. These two type of oil
are the basic raw material for ETAB soap factory to produce higher quality of soap. Produce
from vegetable.

Dolomite: It is one of the most important raw materials that gave a highest profit for the
company. B/c it is Auxiliary raw material used to increase the weight of the soap so no any
function in the soap except weight, due to this reason it should be added in the mixer.

Perfumes: The chemical gives a good odor to the soap. To prevent caustic soda from eating
up the perfume, it must be added as late as possible in the mixer.

Colorants: is an auxiliary raw material used for dyeing the given soap. It must be added in
the mixer at final soap processing step because heat dries it, cracks and separate itself from
the soap.

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Lotion: used to increasing moisture attracting capacity of glycerin and remains your body
shiny.

Titanium oxide: This is a powder form raw material that is used to make the soap white as
much as possible .it does not react with any of material used but it stays as it is by owning its
color resulting changing of solution color to white.

Hydrogen peroxide: is an oxidizing agent also important to avoid bad smell of oil in
bleaching and neat soap drying (atomizer) acting like deodorant.

Hypo chlorate: is used for precipitate impurity and avoid bad smell of oil in bleaching.

Alemneh clay: This is a substance used for refining purpose. In bleaching process alemneh
clay has a high degree of formation of precipitate and increases the purity of oil.

Water: water has many applications. Some of them are the following:

 To increase the moisture in mixer when the composition is dry.

 To homogenize (sticky) the required ingredients in mixer.

 To generate steam energy in boiler
 To dissociate solid sodium silicate.
 To dissolve (hydrolyses) the caustic soda in saponification.
 To cool the machine.
Sodium silicate: raw material that used for: -

 Foaming
 binding
 shiny

2.6.2 Sodium silicate melting

It is a white powder that is readily soluble in water, producing an alkaline solution. Sodium
silicate (Na2SiO3) is a silicate compound which is formed from the reaction of sodium
carbonate and silicon dioxide and used in different chemical and process industries such as in
cement, in textile, soap and others due to its variety of property (binding nature, coagulant
aid, cleaning aid, preservative, adhesive etc.).

Properties of sodium silicate which allow it being used in soap industry;

 It is a binding agent which protects the cracking of the final product (soap).

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 Soluble Na2SiO3 keeps particulate solids suspended in the wash water by modifying an
electrical charge on the surface of solid particles.
 Its ability to form foam, it makes the soap shiny and provide constant PH.

2500 kg sodium silicate and 2500liter soft water is added to sodium silicate melter and steam
having a pressure of 5-8 bars, is received from boiler distributed in to the melting tanker at
the bottom within 12 steam entrance lines which are connected to the melter in different
sides and gives heat to the existing sodium silicate by direct contact till concentration
matches our requirement. The concentration should be between 42-45 degree buame. then it
is pumped to a temporary storage tanker by opening the valv

2500 kg Na2SiO3 2500LH2O

Residue
Na2SiO3
(42-45%) concentration
MELTER
1:1 ratio
Steam
Figure 3 process flow diagram of sodium silicate melting

2.6.3 Tallow melting

In this process, first about 5000kg tallow is added into each of the three melting tankers and
then steam is received from boiler and distributed through tube coils placed inside the
tankers. Then the three melters are allowed to be heated to an optimum temperature ranging
from 90-1000C by using steam (5-8 bars) by direct contact method. The process of melting
animal tallow by using steam as a source of heat in order to extract fatty acid oil. The steam
is sprayed into the tallow within the holes of the tube coils this is done for about 2-3 hour
until required amount of oil is extracted from tallow. It is detected by immersing long steel to
the tallow from top to bottom. If the steel immerses simply to it without requiring power,
required amount of oil from tallow is melted but if it requires power to immerse it, there
exists some unmelted tallow so we have to heat up further. After the extraction process
followed by cooling process (30minut) is completed, since the heat transfer between tallow
and steam is without medium, steam condenses and too much water is mixed with the oil
then by density difference the oil occupy the upper layer and mixture of water with residue
settle to the bottom of the melting tanker, then about 1600kg of residue is removed from each
of the individual melter at the bottom. And the extracted oil from the three melters is flow

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into a temporary storage tanker. Almost 4800kg of residue removed from the three tankers
and mixed with wood shavings to be used for the purpose of firing in wood boiler. The oil is
pumped to bleacher for clarification and bleaching purpose. Here one new additional
technology is applied by ETAB soap factory this is absorber which reduce the bad odor
leaving the company to the environment which cause disease. But now a day ETAB soap
factory use water to absorb the smell. The water pumped by pump and circulate encounter
clockwise and reduce the smell leaving the company.

5000kg tallow 5000kg tallow 5000kg tallow

Melting Melting Melting Oil

Tanker 1 tanker 2 tanker3
Temporary
SteamSteamSteam steam steam Bleacher
Storage
Pump
Tank
Residue (1600kg) Residue (1600kg) Residue (1600kg)
Figure 4 process flow diagram of tallow melting

2.6.4 Bleacher of oil

A device used to remove unpleasant odor and impurities remaining in the oil processed from
tallow. Bleaching is important to increase the quality of the fatty acid oil. Chemicals used for
this process are hypo chlorate and alemneh clay used to settle out the impurities from oil. In
ETAB soap factory, four bleaching tankers are available both of them has the same function
and the same operation parameter. In the process of bleaching one batch fatty acid oil, which
is required to be bleached, is pumped from temporary storage tank and filled into the first
bleaching tanker and the next batch is allowed to enter the next bleacher. And then, the oil is
heated to a temperature of (90 – 100 0C) by supplying steam energy through tube coils. Then
4% of alemneh clay is added in 1kg oil. The use of alemneh clay is to precipitate impurities.
Then after a period of time (about 30 minute) two layers are formed inside the bleacher due
to density difference between the impurity and oil. The oil covers the top layer and the
bottom layer contains Impurities. At the end the valve is opened then the oil is drained and
packed in barrels and stored to be used later in blending operation. but know a day they stop
bleaching processes in order to minimize cost.

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Oil either hypo chlorate or clay

Temporary
storage tank Bleached
Pump Bleached oil
tank

Figure 5 process flow diagram of oil bleaching process

2.6.5 Batch formation and oil blending process

During batch formation process, types of palm oils (PFAD and RBD) and oil extracted from
tallow are melted together by placing 16 barrels on the bed (provided for this purpose) and
supplying steam into the barrel. Then the oils flow into the mixing tank and mixed together.
In ETAB soap factory only five types are formed. These are genuine (GN), build
(BL1&BL2), filled (FL1&FL2). Blending is the process of homogenizing oils that are mixed
in batch formation and stabilizing the oil by separating water & some impurities from oil. In
this process the mixed oil is pumped into the blending tanker and heated by steam energy
until the temperature reaches (90 – 100 0 C) and then it is allowed to stay about 30 minute.
Within 30 minutes, the water present within the oil settles down to the bottom due to its
higher density than the oil and impurities (if there) are also settled being dissolved by water
to form residue. Then the residue is drained and flows through into waste water tank
provided underground. Finally, the pure oil is pumped into saponification room to react with
NaOH solution to form soap solution.

Table 2 Types of slurry and amount (recipe) of different types of oil in each slurry

Types of slurry Amount of Amount of RBD Amount of Amount of

PFAD in barrel in barrel normal tallow in kera tallow
barrel
Genuine (GN1) 6 10 0 0

Build (BL1) 8 0 4 4

Build (BL2) 6 2 4 4

FILLD(FL1) 0 0 8 8

FILLD(FL2) 0 0 8 8

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16 barrel (PFAD, Bed for Temporary pump

melting
storage tank
different
RBD &Tallow oil) steam steam steam
oil types

Oil pump

Steam Saponifica Residue Residue Residue

tion room

Figure 6 process flow diagram of oil melting and blending

2.7 Soap production section

2.7.1 Saponification process

Saponification is used to describe the chemical process that results in the formation of soap.
Fats and oils contain compound what we call fatty acid. These fatty acids are bound to
glycerol to form triglycerides. In the presence of a strong base such as sodium hydroxide, the
triglycerides are breakdown to form the metal salt of the fatty acid. This reaction is called
saponification which literally means the soap making.

Crutcher is huge kettle for preparation of soap from the reaction of oil with caustic soda. In
ETAB soap factory, the saponification process is performed by neutralization reaction. In
neutralization process the reaction between oils (which come from blending) with caustic
soda solution form neat soap and water condensate. In this room protective ware for head,
face, hand, and arm covering should be worn to protect us from dangers since the reaction is
exothermic sometimes the mixture blows up when there is over temperature. In
saponification process, first 1200 litter water is added into the Crutcher and (400kg for
GN,425kg for BL1, BL2 and 475kgfor FL1, FL2) caustic soda (NaOH) is added for all batch
type in solid form. Water is used to dissolve NaOH to form alkaline solution of NaOH. Then
the blended oil at a temperature of (90 – 100 0C) is pumped from blending tanker into
Crutcher and allowed to react with caustic solution. The reaction is activated by agitator.
Then after a period of time we take sample and measure its free caustic value to know how
much of caustic solution is left freely without reacting with the oil. If high amount of caustic
solution left freely, it should be allowed to further reaction. Then sodium silicate (17cm 0r
962.2kg) is allowed to be mixed with the soap solution. Sodium silicate binds the soap

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solution to be stable and increase its foaming capacity of soap and also gives the soap
sticking behavior. Then finally the soap solution flows into the feed tank in which the soap
solution is heated (to flow into atomizer easily) by steam through the jacket of this tank.
Then the soap solution is pumped from feed tank to atomizer.

Figure 7 Crutcher (reactor) (source: from company manual book)

2.7.2 Temporary storage (feed tank)

A small Crutcher type that is important for accumulation of slurry for short period of time
that comes from the larger Crutcher through a pipe by direct pumping system. It has its own
use. Its use is;

 To increase the efficiency of the pump working life time.

 Important to further homogenize the soap solution.
 To keep optimum temperature of the slurry that is used for an input to the atomizer.

2.7.3 Atomizer with Cyclone and Condenser

Atomizer

As the name Indicates atomizer is equipment that converts appearance of slurry to atom size
or shape. It is used to convert the liquid soap in to droplet by sacking out its moisture content
due the effect of vacuum pleasure created using a vacuum pump.

The atomizer is like a dryer, important for changing slurry pumped from saponification
temporary storage room to cake form by absorbing water in side of it through the help of
cyclone and condenser. Inside of the atomizer there is a spray dryer that spray the slurry in
particle size by internal heating system. In atomizer, first liquid soap is pumped from feed
tank and is sprayed into the spray chamber through a feed pump. Separated from soap with

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some fine soap particles are sucked by the vacuum pump and when it reaches to two
cyclones separation made between vaporized moisture and fine particles due to density
difference. Fine particles drop to the bottom of one of the two cyclones while the moisture
passes into the second cyclone. In the condenser, cold water that come from cooling tower is
placed and highly pressurized steam combines with the cold water placed inside the
condenser to form ice. Then (120 kg forGN,60kg forBL2,30kg for BL1and 90kg for FL2,
FL1) of hydrogen peroxide is added to the soap or hot cake purposely used for up grading
the quality or to make white of the cake and avoid bad odour. Finally, drayed soap is scraped
by scrapers from the internal walls of the spray chamber, and then it falls to the underneath
plodder and it is extruded into pellets or continuous bars. In nature hydrogen peroxide goes
slow reaction so that the chips (pellets of soap) should be stored for a period of 48-72hours to
lead for completion of its reaction time.

Figure 8 Atomizer (soap dryer)

Cyclone separation
Substances goes to the cyclone are vapor and some very fine soap particles having very
minimum mass. Cyclone separates them by density difference in which the vapor pass to
condenser overhead condenses the evaporated water and changed to liquid in one part of
cyclone but vapors condensed till they reach cyclone and very fine soaps are stored on the
other parts of the cyclone. The vapor is then condensed and transported to bore hole.

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Figure 9 cyclone

Condenser (booster system)

It is important to condense the vapours that sacked out by vacuum pump from the atomizer
in the process. In booster system, steam is received from boiler and enters into cylindrical
container which is connected by nozzle to the condenser. The condenser receives cold water
from cooling tower. When steam passes through nozzle, its pressure increases and enters the
condenser with a very high pressure. When highly pressurized steam combines with cold
water, there occurs a formation of ice. Soaps that are pumped from the temporary storage
tank (feeding tank) contain high amount of water with a high amount of temperature then
vapour rises up until it reaches a condenser. When the vapour reaches the condenser it
combines with ice and become condensed.

2.8 Finishing processes

2.8.1 Mixers

Mixer is usually the first machine of a soap finishing line. The main purpose of a soap mixer is to
amalgamate the soap noodles (chips) with colorant, fragrance, solid/ liquid additives and fillers.
A batch mixing process typically consists of three sequential steps: weighing, loading and mix
components like chips, dolomite and other ingredients. Now mix them till homogenize. Add
water for batches of mixers that contain dolomite and batches that contain dry chips to increase
homogenization. Some additives like perfumes, colorants, lotions, titanium and sodium silicate
depend on the type of soap to enhance some of its properties in batch mixing all ingredients are
loaded into a mixer and mixed for duration until they are homogenously distributed or mixed.
The retention time in a batch mixer is normally arrived at based on trials where in the time
required for achieving the desired level of product homogeneity is established in case of our
company; ranges from 12-15 minute based of the type of ingredients that was mixed. The
resulting mix is then discharged out of the mixing vessel into miller.

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Figure 10 mixer (source: from manual book)

2.8.2 Millers

Next to mixing the chips directly pass to miller at the bottom of the mixing tank. There are
two roller mills placed bellow the mixing tank. Milling is used for homogenization of the
soap by eliminating granules of abnormal size and hardness contained in soap paste, thus
making it uniform and very fine grain by touch. Then soap by using belt conveyor
transported to plodder.

2.8.3 Plodder

The miller soap is then transported to the plodder for the purpose of giving the shape of soap.
Plodder is achieving texture (appearance) of soap. In plodder vacuum pump is used to
prevent cracking of soap by suck air. Finally, the moulds soap is continuously extruded from
the plodder into the stamp.

Figure 11 plodder (source: from manual book)

2.8.4 Press (stamper)
Stamping is the use of special stamp (either electric or manual, in our case it is electrical) and
trade marks on the products (soap products).

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2.8.5 Cutter

From soap moulds and stampers the soap bar is then feed to the soap cutter for cutting of
billets of fixed length. Cutter speed is normally synchronized with soap bar extrusion speed
from cutter by adjusting air supply to the pneumatic system motor (piston). There is a valve
which is called solenoid valve which control the air supply to the piston. The valve is
controlled by electrical signal. When the required length of soap bar comes out from the
stamp the signal senses the solenoid valve and the valve allow the piston to be compressed in
this case the piston pull down the cutter and immediately the valve supplies air to the piston
to expand and pull the cutter up. This process continues until the whole soap bar outs from
the plodder. Finally, from cutter the pieces of soap are transported to packaging area with a
belt conveyor.

2.8.6 Packaging of products

This is the final process of the soap production in which the final product is packed with a
suitable packaging material. Before the soap is packed, it should be tested in laboratory to
check its parameter such as TFM (total fatty matter), its weight, moisture, ethanol insoluble
matter and free –caustic.

Steam Steam HCLO-4 oil vapor steam vapor steam vapor

Tallow fine chips
Refiner Bleacher Blender Feed tank
Creature
Waste waste waste steam NaOH Na2SiO3
H2O2

Cutter Plodder Miller Chips

Mixer Atomizer
Storage

Packaging Condenser Cyclone

Figure 12 Over all process flow diagram of soap production

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2.9 Quality and operation parameters

2.9.1 Quality controlling and assurance parameters

during quality control and assurance process the quality parameters of raw materials,
intermediate products and final products are tested in order to check whether these
parameters agree the standard or not. If the parameters agree with the standard value, then it
is assured. But if it is not agree with the standard value with high variation, the raw materials
are rejected. The intermediate product should be reprocessed until its parameters agree with
the standard value. And if the final product doesn’t agree with the required parameter it is
recycled again. The following are the main quality parameters of the soap production
process;

Acid Value: indicates the proportion of free fatty acid present in oil or fat and may be
defined as the number of milligrams of caustic potash required to neutralize the acid in 1 g of

the sample. A high acid value indicates a stale oil or fat stored under improper conditions.

Moisture content: The moisture should agree with the standard value. For example, if the
moisture of soap exceeds the standard, cracking will occur when it exposed to air later. If the
moisture is lower the compaction of so will not be effective.

Free fatty acid: the percentage of the oleic acid in the total sample. It indicates the degree of
spoilage that has taken place.

Ethanol insoluble matter: the components of soap that is insoluble in ethanol. It is used to
measures the solubility of soap in polar solvent.

Free caustic: the percentage of alkali that stays freely after saponification reaction has been
takes place. It measures the amount of caustic soda that is not neutralized by the oil. High
free caustic value means there is free alkali on the soap product which irritates our skin when
we wash with the soap.

Hardness of water: hardness of water describes the concentration of multivalent cations in

the water.

Purity of raw materials: the purity of different raw materials should be tested in laboratory
before being processed. The following are caustic, oils and dolomite.

Weight of the soap: the weight of the soap product is analyzed and it should meet with its
standard. If not, it indicates that the soap loses some ingredients.

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Concentration of Na2SiO3: it describes the percentage of solid sodium silicate in the

solution. Its standard is (42 – 45 degree) %. If it is below 42% the soap can’t be built
effectively and since sodium silicate increase the emulsifying property of soap, the soap will
lose this function if Na2SiO3 is diluted. If the concentration is high, it will be coagulated and
can’t be effectively mixed with the soap mixture and also it will form a sticky solid on the
surface of the soap.

Saponification Value: It is a measure of the average molecular weight (or chain length) of
all the fatty acids present. The long chain fatty acids found in fats have low saponification
value because they have a relatively fewer number of carboxylic functional groups per unit
mass of the fat and therefore high molecular weight.

2.9.2 Operating parameters

The standard for some parameters is set by making analysis in laboratory. The following are
operations parameters in the production;

Reaction time: the reaction time in a saponification process is (1.5-2.5hours). If the reaction
time is below 1.5 hours the ingredients may not be reacting properly to form soap. But if it
exceeds 2.5 hours not important for company.

Mixing time: the mixing time in mixing process is (12 – 15 minute). If the mixing time is
below 12 minute, the ingredients may not be mixed properly with the soap noodles. But if it
exceeds 15 minute, the mixture will dry and can’t be compacted effectively in ploddering
operation and also can’t be easily pass though the ploddering machine.

Mixing ratio: while producing a specific type of soap, the mixing ratio should be properly
controlled in order to produce soap with the required quality.

Proportion of different oils: the proportion of different oils should be maintained properly.
This also used to maintain the quality of soap.

Oil temperature: the temperature oil entering to saponification should be (90 – 95) ºC. If it
is lower the saponification reaction will be inactive. If it is over temperature the reaction will
aggravate and makes the soap solution to blow up which causes loss of material.

Steam pressure: the pressure of steam produced in boiler is (5 – 8bar). If the pressure is
below 5bar, the steam will be unable to supply the required energy to the specific unit
operation. If it is over 8bar the boiler can’t carry it because it is beyond its capacity.

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3. PROJECT (HARD WATER TREATMENT)

For ETAB soap factory water is main raw materials that perform many operations. ETAB
soap factory use ground water for different purpose. Water in the ground is the mixture of
different impurity, dust particle and also hard ions (especially Ca+2 and Mg+2) that affect the
production equipment and reduce the lather of soap. The factory uses this raw hard water
without any treatment. So this hard water forms a scale of calcium and magnesium minerals
that can contribute to the inefficient operation or failure equipment and Pipes can become
clogged with scale which reduces water flow and ultimately results in pipe replacement. So
in order to remove this problem hard water must be treated before being used to any
operation.

An excellent way to determine water hardness is to perform a complexometric titration using

a standard ethylenediaminetetraacetic acid (EDTA) solution. Due to steric hindrances, EDTA
will complex with calcium and magnesium in a one- to-one molar ratio. The endpoint in this
experiment will be determined using Eriochrome Black T, which serves as excellent
indicator. The indicator imparts a pink color to the solution while there are calcium and
magnesium ions that have not complexed with EDTA. Once the endpoint has been reached
and there is no more uncomplexed Ca+2, Mg+2, the indicator will give a blue color. No hint
of pink color will be left.

3.1 Statement of the problem

In ETAB soap factory hard water is not treated and this has its own negative effect on the
company. Hard water can cause many problems in factory, including it will cause buildup of
lime scale in pipes causing reduced flow and cause pipes to need to be replaced, in cooling
tower can reduce the effectiveness of heat transfer, causing increased running costs and it can
cause corrosion in tower, pipes and in different machines leading to costly repairs or
replacement of this equipment’s, in boilers and similar machines it will build up and reduce
heat transfer, pushing up operation cost and reduce life span of machines like boiler. And
also this hard water cause soap solution to form a white precipitate (soap scum) instead of
producing lather, because the 2+ ions destroy the surfactant properties of the soap by forming
a solid precipitate (soap scum). Because of this all reason I am motivated to do this project
work.

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3.1 Objective
General objective
 The main objective of this case study is to eliminate the hard ion and other impurity
from ground water by using water softener method.

Specific objective

 To increase foaming of soap i.e. to eliminate the production of insoluble scum formed as
a result of the interaction between calcium and magnesium ion with fatty acid found in
soap.
 To avoid or minimize corrosion.
 Understanding the effect of hard water on soap product and soap production equipment.
 Understanding how to treat hard water by using water softener method.
 To increase water flow in pipe.

3.3 Significance of the study

The significance of this study is to eliminate the hard ion and other impurity from ground water
by using water softener method.

3.4 Scope of the study

This case study helps to reduce problem associated with hard water application in case of ETAB
soap factory

3.5 Material and Method

 Equipment used

Beaker, volumetric flask, plastic gloves, conical flask, test tubes, measuring cylinder,

 Chemicals

Ethylenediaminetetraacetic acid (EDTA), water, zeolite (Na2Al2SI2O8),

 What method you are using and develop the mechanism of hardness removal

The methods for soften hard water through Zeolite process. Why this case study selects
zeolite process:-

 It removes hardness up to 10ppm.

 The process automatically adjust itself for variation in hardness of incoming water.
 Requires less time for softening.

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 The maintenance and operation is easy and does not require special skills.
 Equipment’s are compact and requires less space.
 It does not form any precipitate or sludge.

3.6 Result and Discussion

Process of softening hard water via zeolites
First the ground water must be treated by sand bed filter in filtration tanker in order to
remove the suspended mater otherwise the turbidity will clog the pores of zeolite bed,
thereby making it inactive. In filtration tanker raw water draws on the sand and the large
debris such as sticks, leaves, rubbish and other large particles are separated from raw water
then after the clean raw water passes through the sieve into zeolite process.

Zeolite process is a process of softening hard water via ion exchange technique using the
chemical compound zeolite. Process for softening of water by zeolites process, hard water is
percolated at specified rate through a bed of zeolites, kept in a cylinder. The hardness causing
ions (Ca2+, Mg2+, etc.) are retained by zeolites as CaZe and MgZe while the outgoing water
contains sodium salts. Ze means zeolites

Reactions Inside a cylinder

Na2Ze + CaSO4 CaZe +Na2SO4

Na2Ze + MgSO4 MgZe + Na2SO4

Na2Ze + Ca (HCO3)2 CaZe + 2NaHCO3

Na2Ze + Mg (HCO3)2 MgZe + 2NaHCO3

These reactions are continuous until the active site of sodium in zeolite complex compound
is all occupied by Mgze and Caze. Carbonate and sulfate of sodium pass together with water
which have almost negligible effect since its hardness is very small so no need of water
treatment. But, after some time the zeolite is completely changed into calcium and
magnesium zeolite at this time the zeolite bed gets exhausted. Then we have to stop the water
flow to be regenerated.

Regeneration process
After some time, the zeolite is completely converted into calcium and magnesium zeolites.
Hence the bed ceases to soften water i.e., it gets exhausted, at this stage, the supply of hard

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water is stopped and the exhausted zeolite is reclaimed by treating the bed with a
concentrated solution of sodium chloride (brine). The reaction taking place is

CaZe (or, MgZe) + 2NaCl Na2Ze + CaCl2 (or, MgCl2)

Exhausted zeolite brine reclaimed zeolite washings

The washings are led to drain and thus the regenerated zeolite bed is used again for softening
purpose and the softener water is send to soft water storage tank. Then the soft water is
pumped from the storage tanker to any unit operation that we want to use like boiler,
saponification process, cooling tower and mixer etc. The schemes for softening and
regeneration processes are represented as below.

Brine for regeneration

Sand Brine
storage
Raw water filtration NaCl
Zeolite be Zeolite Solutio
from tanker bed n
undergrou Pump 2
nd Zeolite be
pump Soft water Figure
Soft water Waste storage
storage MgCl13:
2 and
Zeolite
CaCl2
process
Soft water water
Boiler Saponification Cooling Mixer
treatment
storage Waste storage
process tower
MgClflow
2 and
diagram
CaCl 2 Z
Boiler Figure 14 Zeolite process water treatment flow diagram
Mixer
eolite bed
Saponification Cooling
Brine
Sandprocess tower
storage
NaCl
filtration Solutio
Raw water tanker n

from
undergrou
nd

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4. CONCLUSION AND RECOMMENDATION

4.1 CONCLUSION
So raw water entering an industrial plant often needs treatment to meet tight quality
specification to be of use in specific industrial processes. By using zeolite water softener we
can prevent scale formation and corrosion due hard water. In boiler, scale is a problem
because it insulates and heat exchange becomes less efficient as the scale thickens, which
waste energy and money. Scale also narrows pipe widths and therefore increases the energy
used in pumping. Corrosion can also lead to leaks, which in a pressurized system can lead to
catastrophic failures. Due to this and other reason softening of hard water by using zeolites is
very important to ETAB soap factory to save energy, time, boiler and pipe life span and cost.

4.2 RECOMMENDATION
 To solve rancidity problem, the raw tallow should not be accumulated for long time.

 The residue discarded from bleaching and blending operations is released to underground
without any treatment process. This will cause pollution of underground water. So the
residue must be treated before being released.

 In the boiler, the distributer which is used to distribute the steam from the boiler to different
unit operations releases the condensed steam (steam which have low pressure) as a waste to
the environment, this released condensed steam was already boiled which have
approximately 4-5 bar pressure, so if we can recycle it instead of removing it to the
environment we can improve the capacity and speed of the boiler, to do that first we store
that steam in the temporary storage tank or directly insert it to the boiler so we can get more
steam at a short period of time. Only needed a pump which used to return the water and a
tank for storage.
 The pipe from the blending tank to the cruncher tank is not covered by jacketed vessel. so in order to
kept the optimum temperature, the pipe should be covered jacketed vessel like insulter.
 The company should be found a proper storage area for the tallow to make the oil
preparation section safe and clean.
 Ions which found in the hard water cause the deterioration of boiler, pipe lines and make the
soap solution to form a white precipitate (soap scum) instead of producing lather, because of
the 2+ ions in hard water destroy the surfactant property of the soap by forming a solid
precipitate. So water must be treated by using zeolite process to prevent the above problems,
to reduce maintenance cost and to extend the life span of machines.

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REFERENCE
1. Shreve chemical process industry
2. Different Files from ETAB soap factories
3. http://www.purewaterproducts.com/articles/removing-hardness
4. https://www.tutorvista.com/content/chemistry/chemistry/hydrogen/methodshardnesswater
.php
5. https://www.youtube.com/watch?v=D_eSi5YnspA
6. Perry chemical engineers book
7. Soap book of Gutenberg
8. Felder (elementary principles of chemical processes)
9. By Dr. Edward Group DC, NP, DACBN, DCBCN, DABFM Published on May 21, 2014,
Last Updated on June 2, 2014
10. http://www.water-research.net/hardness.htm
11. WATER TREATMENT PLANT OPERATION.2nd Edition (1989). Volumes 1 and 2.
Kenneth D. Kerri. California State University, 6000 J Street, Sacramento, CA 95819-
6025. Phone (916) 278-6142

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