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  • 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

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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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    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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    Flash Points of Selected Pure Liquids Application to the Correction of

    Probably Erroneous Flash Point Values. Journal of Physical and

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    [3] Chakradhar, R. S., Nagabhushana, B. M., Chandrappa, G. T., Ramesh,

    K. P., & Rao, J. L. (2004). Solution combustion derived nanocrystalline

    Zn2SiO4:Mn

    phosphors: A spectroscopic view. Journal of Chemical Physics, 121,

    1025010259 El Mir, L., Amlouk, A., Barthou, C., & Alaya, S. (2007).

    [4] Synthesis and luminescence properties of ZnO/Zn2SiO4 /SiO2

    composite based on nanosized zinc oxide- fi . : Condensed Matter, 68,

    412417

    [5] Inoue, Y., Toyoda, T., & Morimoto, J. (2008). Photoacoustic spectra

    on Mn-doped zinc silicate powders by evacuated sealed silica tube

    method. Journal of Materials Science, 43, 378-383

    [6] Lee, B. I., & Lua, S. W. (2000). Synthesis of nanoparticles via surface

    modification for electronic applications. Journal of Ceramic Processing

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    [7] Mai, M., Feldmann, & Claus. (2009). Two-color emission of

    Zn2SiO4:Mn from ionic liquid mediated synthesis. Solid State Sciences,

    11, 528-532

    [8] Natarajan, V., Murthy, K., & Kumar, M. J. (2005).

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    investigations of Zn2SiO4 co-doped with Eu3+and Tb3+ ions. Solid State

    Communications, 134, 261-264

    [9] Takesue, M., Hayashi, H., & Smith, R. L. (2009). Thermal and

    chemical methods for producing zinc silicate (willemite): A review.

    Progress in Crystal Growth and Characterization of Materials, 55, 98-124

    [10 ] Tani, T., Takatori, K., & Pratsinis, S. E. (2004). Evolution of the

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    Zinc Oxide/Silica Particles by Spray Combustion. Journal of the

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    Ceramic Society, 87, 365-370


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