Plant design of inorganic zinc silicate paint 2014
A PROJECT REPORT ON
PLANT DESIGN OF INORGANIC ZINC
SILICATE PAINT
Submitted to the University of Pune, Pune
in Partial Fulfillment of the Requirements
For the Award of the Degree of
BACHELOR OF ENGINEERING (CHEMICAL)
BY
Gajanan R. Hange
(Gr. No. 111251)
Pawan V. Jamadar
(Gr. No.111330)
Sandeep R. Bhagat
(Gr. No. 111020)
Department of Chemical Engineering
BRACTS Vishwakarma Institute of Technology, 666, Upper Indiranagar, Bibwewadi, Pune 411 037
Plant design of inorganic zinc silicate paint 2014
Chemical Engineering 2014 ii
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ABSTRACT
Successful synthesis of nanocrystalline Zn2SiO4 powders using solid
state reaction of the ZnO powder precipitate and amorphous cristobalite
SiO2 powders from processed rice hull ash at 800T1000oC is presented
in this study. ZnO powders were grown by chemically reacting
stoichiometric NaOH and ZnSO4. The solid state reacted powders were
characterized using scanning electron microscopy (SEM) with energy
dispersive x-ray spectroscopy (EDX), Fourier transform Spectroscopy
(FTIR) and x-ray diffraction (XRD). Microscopic analyses of the
Annealed powders were consistent with reported morphological
structures of Zn2SiO4. FTIR results indicate the presence of ZnO4 and
SiO4 groups corresponding to Zn2SiO4. XRD results further revealed that
Zn2SiO4 powders were synthesized at the reaction temperatures of 900
and 1000oC with onset growth at 800oC. The method used in this study
shows that Zn2SiO4 can be grown at a much lower temperature
(800T1000oC) compared to the reported temperature of synthesizing
Zn2SiO4 through solid-state reaction. The Zn2SiO4powders exhibit
dominant a-axis orientation and the average crystallite size for zinc
silicate powders annealed at 1000oC is about 33 nm. The results suggest
that the Zn2SiO4 powders are promising materials for phosphor
applications. Using SiO2 from RHA in the synthesis of ZnSiO4 increases
the value of rice hulls and as a result becomes beneficial to rice farmers
and that RHA collection and utilization policies has to be incorporated in
local governments.
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ACKNOWLEDGEMENT
It gives me a great pleasure to find an opportunity to express our deep and
sincere gratitude to all those who have been directly or indirectly related
to this project
I specially thank our internal guide Prof. A. R. Gangwal for his
tremendous support, timely guidance and for sharing his experience and
knowledge, for the valuable direction that keeps us going and inspires to
perform better
Also, I cannot overlook the fact that without the support of our Head of
Department Prof. Dr. D. S. Bhatkhande our work would not have been
accomplished in its entirety
Last but not the least we would like to convey our heartiest thanks to all
our friends who time to time have helped us with their valuable
suggestion during our project report
SANDEEP BHAGAT
GAJANAN HANGE
PAWAN JAMADAR
Bansilal Ramnath Agarwal Charitable Trusts
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Chemical Engineering 2014 v
VISHWAKARMA INSTITUTE OF TECHNOLOGY
(An Autonomous Institute Affiliated to University of Pune)
666, Upper Indiranagar, Bibwewadi, Pune 411 037
APRIL 2014
CERTIFICATE
It is certified that the project work entitled
PLANT DESIGN OF INORGANIC ZINC SILICATE PAINT
Submitted by
Gajanan R. Hange Gr. No. 111251 Roll No.22
Pawan V. Jamadar Gr. No. 111330 Roll No.23
Sandeep R. Bhagat Gr. No. 111020 Roll No.06
is the original work carried out by them under the supervision of Mr.Prof. A. R.
Gangwal and is approved for the partial fulfilment of the requirement of University
of Pune, Pune for the award of the Degree of Bachelor of Engineering (Chemical)
This Project Work has not been earlier submitted to any other Institute or University
for the award of any degree or diploma.
(Prof. A. R. Gangwal) (Prof. Dr. D. S. Bhatkhande)
Guide, Head,
Department of Chemical Department of Chemical
Engineering Engineering
TABLE OF CONTENTS
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Page
Abstract iii
Acknowledgements iv
Certificate v
Table of Contents vi
List of figures vii
Chapter 1 INTRODUCTION 1
1.1 Physical properties of inorganic zinc silicate paint 2
1.2 Chemical properties of inorganic zinc silicate paint
1.2.1 Curing mechanism
1.2.2 Film cure 1.2.3 Bubbling/Pinholes 1.2.4 Mud cracking
3
4
4
5
1.3 Methodology 6
1.4
1.5
Advantages and disadvantages of inorganic zinc silicate
Paint
Applications of zinc silicate paint
1.5.1 Segments
1.5.2 Objects
8
9
9
10
Chapter 2 LITERATURE SURVEY 11
2.1 History of paint science and technology 11
2.2 Components 14
2.2.1 Binder, vehicle, or resins 14
2.2.2 Diluent or Solvent 15
2.2.3 Pigment and Filler 16
2.2.4 Additives 17
2.3
2.4
2.5
2.6
Application of paint
Failure of paint
Dangers
Indian paint industry
2.6.1 Brief Introduction
2.6.2 Size of the Industry
2.6.3 Total contribution to the economy/ sales
2.6.4 Top leading Companies
2.6.5 Latest Development
18
19
21
22
22
22
23
23
23
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Chapter 1
INTRODUCTION
The zinc silicate primer has to its the name the promise of perfection for
the long run. It is useful in highly corrosive areas like chemical factories
and refineries etc. Zinc is a self sacrificial metal its gives full protection
to the metal. Although inorganic coatings can be formulated with a
variety of inorganic binders, they are generally made from polymers
based on silicon chemistry. By the combination of metallic zinc powder
and silicate binders, inorganic zinc silicate primers have been formulated.
Since their introduction and use in the first part of this century, zinc
silicates have been recognized as the most effective corrosion resistant
primers in the protective industry. Inorganic topcoats are predominantly
formulated with silicon based binders, such as silicone resins, water and
solvent based silicates, silanes and mixtures of organic binders with
silicate binders. Traditionally, long term corrosion protection has been
obtained with inorganic zinc silicates. This is achieved by a combination
of the cathodic protection properties of metallic zinc and the inert
polymer matrix of the inorganic polysilicate binder. The polymeric
structure of the silicate binder, which surrounds the metallic zinc as a
matrix, is represented as a dense cross-linked inorganic polymer structure
of - Si - O - Si - chains. The resulting inorganic zinc silicate coatings
provide excellent resistance to numerous corrosive exposure
environments. They exhibit excellent corrosion protection and adhesion
to the metal substrate, inhibiting under-cutting and rust migration under
the film.
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1.1 PHYSICAL PROPERTIES OF INORGANIC ZINC SILICATE
PAINT
Inorganic zinc silicate act as an anticorrosive primer for
protection of steel .
Inorganic zinc silicate paint is resistant to dry heat up to
4500 C .
Solid content by volume in inorganic zinc silicate paint is
69% .
Recommended dry film thickness for Inorganic zinc
silicate coatings is u to 75microns
Estimated spreading rate of inorganic zinc silicate paint is
up t the 9.2 sq m/l
One of the most important property of inorganic zinc
silicate coating is that it gives cathodic protection to the
metal
The paint is very sensible to application condition .
Drying time for top coating is about 24hrs.
Zinc rich coatings are abrasion resistant and rock hard
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1.2 Chemical properties of inorganic zinc silicate primer
Inorganic zinc rich coatings afford superb corrosion resistance, they are
also rock hard and very abrasion-resistant. They make some of the best
anti-corrosive primers available. Ethyl silicate based inorganic zincs
(Galvit ES600 & Galvit ES510) should be applied at 75 microns (dft).
Because they have a tendency to grip unlike most other coatings, they
may be applied to the faying surfaces of bolted steel joints. Inorganic
zinc-rich primers have excellent resistance to temperatures up to the
melting point of zinc (above 400oC). Inorganic zincs should not be
exposed to acids and alkalis. However, their resistance to organic solvents
and organic chemicals is excellent. The term zinc-rich refers to the
percent by weight of metallic zinc in the cured coating film, which may
range from 50% to 90%. The film is a hard, adherent coating composed
of metallic zinc powder suspended in a silicate matrix
Fig no 1.1 Zinc particles embedded in a silicate matrix
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1.2.1 Curing mechanism
These coatings cure by hydrolysis or reaction with moisture following the
evaporation of solvent. These coatings are typically resistant to rain
showers in one hour or less. High humidity conditions usually accelerate
the cure of ethyl silicates. When the relative humidity is less than 40%,
water may be sprayed on the coating surface to complete the curing
process.
1.2.2 Film cure
To determine if a film has cured a clean cloth soaked in methyl ethyl
ketone (MEK) is rubbed over the coating. A properly cured film should
have no zinc transfer onto the cloth.
1.2.3 Bubbling/Pinholes
The zinc silicate matrix film is quite porous, which can result in bubbling
or pinholes when a subsequent coating is applied. To overcome bubbling
and/or pinholes excessive film builds and overspray should be avoided
and/or removed prior to topcoating. For best control over the spray
application conventional spray is preferred over airless equipment. When
topcoating, apply a mist/tack coat of suitable product, thinned
approximately 25% to seal off the zinc prior to application of a full coat.
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1.2.4 Mud Cracking
Mud cracking (Diagram 1.2) can occur due to a number of reasons, these
include:
Low blast profiles
Excessive film build
Poor ambient drying conditions
Old Product Insufficient ventilation, which is pronounced in concave
corners and cavities
Fig 1.2 mud cracking
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1.3 Methodology
Zinc silicate (Zn2SiO4) is synthesized using equimolar concentrations of
zinc sulphate (ZnSO4) and sodium hydroxide (NaOH) producing zinc
hydroxide (Zn(OH)2). The addition of strong electrolyte (ZnSO4) and
strong base (NaOH) in an aqueous solution results to the exchange of
ions. The formation Zn(OH)2 and Na2SO4 is the product of ion exchange.
Zn(OH)2 is insoluble in water thus it remains as solid in an aqueous
solution. On the other hand, Na2SO4 is soluble in water hence it is in
liquid phase. The reaction proceeds as follows
ZnSO4 (aq) + 2NaOH (aq ) Zn(OH)2(s) + Na2SO4(l).
The resulting solution is filtered and washed with distilled water. The
precipitate is mixed with appropriate amount of silicon dioxide (SiO2) in
water with constant stirring at an elevated temperature of 80oC. Neither
Zn(OH)2 and SiO2 are soluble in water. Thus, no chemical reaction is
expected in the mixing of Zn(OH)2 and SiO2. However, the water is
used as an amalgamation medium to promote the adhesion of Zn(OH)2
particles on the surface of SiO2 creating a nucleation site where Zn(OH)2
particles coat SiO2. The reaction mechanism for this process is
Zn(OH)2(s) + SiO2(s) Zn(OH)2(s) + SiO2(s) + H2O(g).
The precipitate is washed with distilled water and dried at 100oC. The
dried precipitate is annealed at 800, 900 and 1000oC. Solid-solid diffusion
is expected to occur at these temperatures. The mixing stage promote the
adhesion of smaller particle Zn(OH)2 to the surface of SiO2 allowing the
formation of Zn2SiO4 at lower temperature. Thus, the powders annealed
at 800To 1000oC are expected to contain Zn2SiO4 following the process
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2 Zn(OH)2(s) + SiO2(s) Zn2SiO4 + H2O (g).
The resulting powders are characterized using scanning electron
microscopy
(SEM) equipped with energy dispersive x-ray spectroscopy (EDX),
Fourier
transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD).
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1.4 ADVANTAGES AND DISADVANTAGES OF ZINC SILICATE
PRIMER
Some important advantages and disadvantages of inorganic zinc silicate
paint are listed below. These factors are to be considered while its
application to the industrial and on household equipments
1.4.1 ADVANTAGES OF ZINC SILICATE PRIMER
Inorganic zinc silicate paint primer are Very good corrosion
protection
Inorganic zinc silicate paint primer are Very good solvent
resistance
High heath resistance is offered by Inorganic zinc silicate paint
primer
(max 400oC)
Very high mechanical strength is the main advantage of Inorganic
zinc silicate paint primer
Very good adhesion to blast cleaned steel is the useful property of
Inorganic zinc silicate paint primer
Relatively good recoat ability is there for Inorganic zinc silicate
paint primer
1.4.2 DISADVANTAGES OF ZINC SILICATE PRIMER
Alkyl enamels cannot be applied directly over Inorganic zinc
silicate paint primer
Higher application skill required for the application of Inorganic
zinc silicate paint primer
Inorganic zinc silicate paint primer takes long time to dry.
Inorganic zinc silicate paint primer recoat time is more.
Greater than recommended film thickness of Inorganic zinc silicate
paint primer causes mud cracking
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1.5 APPLICATIONS OF ZINC SILICATE PRIMERS
1.5.1 Segments: 1) ships 2) offshore 3) Industry
One of the most important application of Inorganic zinc silicate primer
Is that it is used in marine areas where most of the equipments comes in
to contact with corrosional substances. As zinc is the self sacrificial metal
, it protects the equipments from corrosion . zinc provides the cathodic
protection to the metal against the galvanic corrosion.
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1.5.2 Objects: New constructions / Maintenance Exterior and interior
design , above and below water .
Popular application of Inorganic zinc silicate primer is that it is used in
building sections areas where most of the equipments comes in to contact
with corrosional substances. As zinc is the self sacrificial metal , it
protects the equipments from corrosion . zinc provides the cathodic
protection to the metal against the galvanic corrosion.
Inorganic zinc silicate paint have also found many applications in
Maintenance Exterior and interior design.
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Chapter 2
Literature survey
2.1 History of paint science and technology
In 2011, South African archaeologists reported finding a 100,000-year-
old human-made ochre-based mixture that could have been used like
paint.
Cave paintings drawn with red or yellow
ochre, hematite, manganese oxide, and charcoal may have been made by
early Homo sapiens as long as 40,000 years ago.
Ancient colour walls at Dendera, Egypt, which were exposed for years to
the elements, still possess their brilliant colour, as vivid as when they
were painted about 2,000 years ago. The Egyptians mixed their colours
with a gummy substance, and applied them separately from each other
without any blending or mixture. They appear to have used six colours:
white, black, blue, red, yellow, and green. They first covered the area
entirely with white, then traced the design in black, leaving out the lights
of the ground colour. They used minium for red, and generally of a dark
tinge
Pliny mentions some painted ceilings in his day in the town of Ardea,
which had been done prior to the foundation of Rome. He expresses great
surprise and admiration at their freshness, after the lapse of so many
centuries.
Paint was made with the yolk of eggs and therefore, the substance would
harden and adhere to the surface it was applied to. Pigment was made
from plants, sand, and different soils. Most paints used either oil or water
as a base (the dilutant, solvent or vehicle for the pigment).
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A still extant example of 17th-century house oil painting is Ham
House in Surrey, England, where a primer was used along with several
undercoats and an elaborate decorative overcoat; the pigment and oil
mixture would have been ground into a paste with a mortar and pestle.
The process was done by hand by the painters and exposed them to lead
poisoning due to the white-lead powder.
In 1718, Marshall Smith invented a "Machine or Engine for the Grinding
of Colours" in England. It is not known precisely how it operated, but it
was a device that increased the efficiency of pigment grinding
dramatically. Soon, a company called Emerton and Manby was
advertising exceptionally low-priced paints that had been ground with
labour-saving technology:
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In simple commercial context, the first graph below shows how, in the
US at least (from Census Bureau data), the paint industry continues to be
important and grows with the economy and suffers with the economy. In
fact, as long as one needs to control the appearance of useful or amusing
things, or they need protection, we will always need paint. Even modern
nano- or bio-materials are more often employed as coatings than any
thing else
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In contrast with the sales figures before, the graph below places the rise
of paint technology in the context of some of the external influences
The last graph labels the rise in paint technology with events that
were important from the point of view of alkyd paint
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2.2 components:
2.2.1 Binder, vehicle, or resins
The binder, commonly called the vehicle, is the film-forming component
of paint. It is the only component that must be present. Components listed
below are included optionally, depending on the desired properties of the
cured film.
The binder imparts adhesion and strongly influences properties such as
gloss, durability, flexibility, and toughness.
Binders include synthetic or natural resins such as alkyds, acrylics, vinyl-
acrylics, vinyl acetate/ethylene
(VAE), polyurethanes, polyesters, melamine resins, epoxy, or oils.
Binders can be categorized according to the mechanisms for drying or
curing. Although drying may refer to evaporation of the solvent or
thinner, it usually refers to oxidative cross-linking of the binders and is
indistinguishable from curing. Some paints form by solvent evaporation
only, but most rely on cross-linking processes.
Paints that dry by solvent evaporation and contain the solid binder
dissolved in a solvent are known as lacquers. A solid film forms when the
solvent evaporates, and because the film can re-dissolve in solvent,
lacquers are unsuitable for applications where chemical resistance is
important. Classic nitrocellulose lacquers fall into this category, as do
non-grain raising stains composed of dyes dissolved in solvent and more
modern acrylic-based coatings such as 5-ball Krylon aerosol.
Performance varies by formulation, but lacquers generally tend to have
better UV resistance and lower corrosion resistance than comparable
systems that cure by polymerization or coalescence.
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The paint type known as Emulsion in the UK and Latex in the USA is a
water-borne dispersion of sub-micrometer polymer particles. These terms
in their respective countries cover all paints that use synthetic polymers
such as acrylic, vinyl acrylic (PVA), styrene acrylic, etc. as binders. The
term "latex" in the context of paint in the USA simply means an aqueous
dispersion; latex rubber from the rubber tree is not an ingredient. These
dispersions are prepared by emulsion polymerization. Such paints cure by
a process called coalescence where first the water, and then the trace, or
coalescing, solvent, evaporate and draw together and soften the binder
particles and fuse them together into irreversibly bound networked
structures, so that the paint cannot redissolve in the solvent/water that
originally carried it. The residual surfactants in paint, as well
as hydrolytic effects with some polymers cause the paint to remain
susceptible to softening and, over time, degradation by water. The general
term of latex paint is usually used in the USA, while the term emulsion
paint is used for the same products in the UK and the term latex paint is
not used at all. Paints that cure by oxidative cross linking are generally
single package coatings. When applied, the exposure to oxygen in the air
starts a process that cross links and polymerizes the binder component.
Classic alkyd enamels would fall into this category. Oxidative cure
coatings are catalysed by metal complex driers such as cobalt naphthenes.
Paints that cure by polymerization are generally one or two package
coatings that polymerize by way of a chemical reaction, and cure into a
cross linked film. Depending on composition they may need to dry first,
by evaporation of solvent. Classic two
package epoxies or polyurethanes would fall into this category.
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2.2.2 Diluent or Solvent
The main purposes of the diluent are to dissolve the polymer and adjust
the viscosity of the paint. It is volatile and does not become part of the
paint film. It also controls flow and application properties, and in some
cases can affect the stability of the paint while in liquid state. Its main
function is as the carrier for the non volatile components. To spread
heavier oils (for example, linseed) as in oil-based interior house paint,
thinner oil is required. These volatile substances impart their properties
temporarilyonce the solvent has evaporated, the remaining paint is
fixed to the surface. This component is optional: some paints have
no diluent. Water is the main diluent for water-borne paints, even the co-
solvent types. Solvent-borne, also called oil-based, paints can have
various combinations of organic solvents as the diluent,
including aliphatics, aromatics, alcohols, ketones and white spirit.
Specific examples are organic solvents such as petroleum
distillate, esters, glycol ethers, and the like. Sometimes volatile low-
molecular weight synthetic resins also serve as diluents.
2.2.3 Pigment and Filler
Pigments are granular solids incorporated in the paint to contribute
colour. Fillers are granular solids incorporate to impart toughness,
texture, give the paint special properties, or to reduce the cost of the paint.
Alternatively, some paints contain dyes instead of or in combination with
pigments.
Pigments can be classified as either natural or synthetic. Natural pigments
include various clays, calcium carbonate, mica, silicas, and talcs.
Synthetics would include engineered molecules, calcined clays, blanc
fixes, precipitated calcium carbonate, and synthetic pyrogenic silica.
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Hiding pigments, in making paint opaque, also protect the substrate from
the harmful effects of ultraviolet light. Hiding pigments include titanium
dioxide, phthalo blue, red iron oxide, and many others.
Fillers are a special type of pigment that serve to thicken the film, support
its structure and increase the volume of the paint. Fillers are usually
cheap and inert materials, such as diatomaceous earth, talc, lime, barytes,
clay, etc. Floor paints that must resist abrasion may contain fine quartz
sand as a filler. Not all paints include fillers. On the other hand, some
paints contain large proportions of pigment/filler and binder.
Some pigments are toxic, such as the lead pigments that are used in lead
paint. Paint manufacturers began replacing white lead pigments with
titanium white (titanium dioxide), before lead was banned in paint for
residential use in 1978 by the US Consumer Product Safety Commission.
The titanium dioxide used in most paints today is often coated with
silica/alumina/zirconium for various reasons, such as better exterior
durability, or better hiding performance (opacity) promoted by more
optimal spacing within the paint film.
2.2.4 Additives
Besides the three main categories of ingredients, paint can have a wide
variety of miscellaneous additives, which are usually added in small
amounts, yet provide a significant effect on the product. Some examples
include additives to modify surface tension, improve flow properties,
improve the finished appearance, increase wet edge, improve pigment
stability, impart antifreeze properties, control foaming, control skinning,
etc. Other types of additives include catalysts, thickeners,
stabilizers, emulsifiers, texturizers, adhesion promoters, UV stabilizers,
flatteners (de-glossing agents), biocides to fight bacterial growth, and the
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like. Additives normally do not significantly alter the percentages of
individual components in a formulation.
2.3 Application of paint
Paint can be applied as a solid, a gaseous suspension (aerosol) or a liquid.
Techniques vary depending on the practical or artistic results desired.
As a solid (usually used in industrial and automotive applications), the
paint is applied as a very fine powder, and then baked at high
temperature. This melts the powder and causes it to adhere to the surface.
The reasons for doing this involve the chemistries of the paint, the surface
itself, and perhaps even the chemistry of the substrate (the object being
painted). This is called "powder coating" an object.
As a gas or as a gaseous suspension, the paint is suspended in solid or
liquid form in a gas that is sprayed on an object. The paint sticks to the
object. This is called "spray painting" an object. The reasons for doing
this include:
1) The application mechanism is air and thus no solid object touches the
object being painted;
2) The distribution of the paint is uniform, so there are no sharp lines;
3) It is possible to deliver very small amounts of paint;
4) A chemical (typically a solvent) can be sprayed along with the paint to
dissolve together both the delivered paint and the chemicals on the
surface of the object being painted;
5) Some chemical reactions in paint involve the orientation of the
paint molecules.
In the liquid application, paint can be applied by direct application
using brushes, paint rollers, blades, other instruments, or body parts such
as fingers and thumbs.
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Rollers generally have a handle that allows for different lengths of poles
to be attached, allowing painting at different heights. Generally, roller
application requires two coats for even colour.
2.4 Failure of paint
The main reasons of paint failure after application on surface are the
applicator and improper treatment of surface.
Application Defects can be attributed to:
Dilution
This usually occurs when the dilution of the paint is not done as per
manufacturers recommendation. There can be a case of over dilution and
under dilution, as well as dilution with the incorrect diluent.
Contamination
Foreign contaminants added without the manufacturers consent can cause
various film defects.
Peeling/Blistering
Most commonly due to improper surface treatment before application and
inherent moisture/dampness being present in the substrate.
Chalking
Chalking is the progressive powdering of the paint film on the painted
surface. The primary reason for the problem is polymer degradation of
the paint matrix due to exposure of UV radiation in sunshine and
condensation from dew. The degree of chalking varies as epoxies react
quickly while acrylics and polyurethanes can remain unchanged for long
periods. The degree of chalking can be assessed according
to International Standard ISO 4628 Part 6 or 7 or American Society of
Testing and Materials(ASTM) Method D4214 (Standard Test Methods
for Evaluating the Degree of Chalking of Exterior Paint Films).
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Cracking
Cracking of paint film is due to the unequal expansion or contraction of
paint coats. It usually happens when the coats of the paint are not allowed
to cure/dry completely before the next coat is applied. The degree of
cracking can be assessed according to International Standard ISO 4628
Part 4 or ASTM Method D661 (Standard Test Method for Evaluating
Degree of Cracking of Exterior Paints).
Erosion
Erosion is very quick chalking. It occurs due to external agents like air,
water etc. It can be evaluated using ASTM Method ASTM D662
(Standard Test Method for Evaluating Degree of Erosion of Exterior
Paints).
Blistering
Blistering is due to improper surface exposure of paint to strong sunshine.
The degree of blistering can be assessed according to ISO 4628 Part 2 or
ASTM Method D714 (Standard Test Method for Evaluating Degree of
Blistering of Paints).
Degradation
The fungi Aureobasidium pullulans consumes wall paints.
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2.5 Dangers
Volatile organic compounds (VOCs) in paint are considered harmful to
the environment and especially for people who work with them on a
regular basis. Exposure to VOCs has been related to organic solvent
syndrome, although this relation has been somewhat controversial
In the US, environmental regulations, consumer demand, and advances in
technology led to the development of low-VOC and zero-VOC paints and
finishes. These new paints are widely available and meet or exceed the
old high-VOC products in performance and cost-effectiveness while
having significantly less impact on human and environmental health.
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2.6 Indian paint industry
2.6.1 Brief Introduction
There is a phenomenal growth on the housing sector front with rapid
urbanization and availability of easy to secure housing loans which have
become the prime drivers of growth in the decorative paint segment,
which comprises 70% of the $2 billion Indian Paint industry. An average
increase of growth of about 10% in the automobile sector contributes to
50% of the revenues in the industrial paints segment. Paints can be
classified as Decorative Paints & Industrial Paints.
Decorative Paints are usually meant for the housing sector. Distemper is
mostly affordable by all and used in the suburban and rural markets.
Interestingly, 20% of all decorative paints in India are distempers. Indian
Paint products are highly in demand in countries of United States, China,
India, United Kingdom, Australia, Pakistan, Hong Kong, Canada, etc
forming the turning points in the Paint Industry of India.
2.6.2 Size of the Industry
A large number of Paint outlet or shops have automated/manual dealer
tinting systems. Today India has more than 20,000 outlets in operation,
probably the highest for any country. There are only approximately 7,000
tinting systems in China for a market two and half times of India's size.
30% to the paint industry revenue in India is accumulated from Industrial
Paints. The size of the Paint Indian industry is around 940 million litres
and is valued at approximately $2 billion. The organized sector comprises
54% of the total volume and 65% of the value. In the last ten years, the
Indian Paint Industry has grown at a compounded annual growth rate
(CAGR) of 12-13%.
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2.6.3 Total contribution to the economy/ sales
The market for paints in India is expected to grow at 1.5 times to 2 times
GDP growth rate in the next five years. With GDP growth expected to be
over and above 7% levels, the top three players are likely to clock above
industry growth rates. There are high volumes of low cost distempers sold
in India, which amounts to approximately 200,000 tons per annum at an
average cost of Rs35 per kg ($0.88) at the present rate.
2.6.4 Top leading Companies
Asian Paints India
Nerolac India Paints
Berger
Dulux India Paints
Shalimar Paints
2.6.5 Latest Development
Indian Paint Industry today is about Rs 49 billion sector which has
demands for paints which is relatively price-elastic but is linked to
the industrial and economical growth.
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Indian per capita consumption of paints is at 0.5 kg per annum if
compared with 4 kgs in the South East Asian nations and 22 kgs in
developed countries.
Organized sector in India controls 70% of the total market with the
remaining 30% being in the hands of nearly 2000 small-scale units.
In India 30% accounts for the industrial paint segment in paint
Industry while the decorative paint segment accounts for 70 % of
paints sold in India.
Globally, Indian Industrial Paints segment accounts for a major share
which indicates that this segment offers many opportunities for paint
manufacturers. In June 2009 with a recovery in realty sector, the
production volumes in the sector have substantially recovered. In the year
2009-2010 the Production of paints grew by a robust 25.2% during as
compared to a 40 basis points drop in production in the corresponding
year-ago period.
As the production of passenger cars is expected to grow by 15.3% in
2010-11 the demand for automotive paints will continue to remain
healthy as sales are expected to grow in double-digits. And with realty
majors launching new projects, construction activity is expected to gain
momentum and generate demand for decorative paints. Rise in demand is
expected to be supported by higher supply as the industry is expected to
commission additional capacity in 2010-11.
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Chapter 3
Objectives and future plans
Process Flow Diagram.
Material and Energy Balance
Detail Equipment Design.
Piping and Instrumentation Diagram.
Plant Layout.
Costing and Economics.
Safety and Environmental Studies.
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