1. CALCIUM CARBONATE
1.
PRODUCT CHARACTERISTICS
Calcium carbonate occurs naturally as the principal constituent of limestone, marbel and
chalk.
Natural ground Calcium carbonate has been used for years as the primary constituent of
putty. Since 1945, the processing of natural Calcium carbonate has seen the introduction
of beneficiation by flotation to remove impurities and the development of grinding
processes to manufacture finer products.
The natural ground Calcium carbonate and the precipitated material compete industrially,
based primarily on particle size and the characteristics imparted to the product.
The precipitated types are distinguished by a finer and more uniform particle size, a
narrower particle size range and a higher degree of chemical purity.
Specification
Calcium Carbonate finds applications in diversified sector and the specifications of the
product required by different applications are marginally different.
The specifications of Calcium Carbonate required for various applications are provided.
Rubber industry
Indian standard specification for Activated Calcium Carbonate for rubber industry
IS 917-1976 revision 1980
Description
The material shall consist of Precipitated Calcium Carbonate coated with thin layers of
fatty acids or their salts. It shall be in the form of a free flowing, white powder, free from
visible impurities.
Characteristic
Sieve residue on 150 micron IS Sieve % by
mass. max.
Hydrochloric acid insoluble % by mass, max.
pH
Loss on ignition, % by mass
Mn % bymass max.
Cu% by mass, max.
Total fatty matter % by mass
Requirements
0.01
0. 2
10.5  0.5
43 to 46
0.02
0.005
2 to 3.5
Mixed oxides, % by mass
1.0
CaCO3, % and MgCO3 together % by mass 92
min.
Moisture content, % by mass max.
0.075
The ignition temperature shall be 950  25 deg.C
Cosmetic industry
IS specifications for Precipitated Calcium Carbonate for cosmetic industry
IS No.918-1985
Requirements
Description: The material shall be in the form of fine, white microcrystalline powder
without any taste or odour. It shall be stable in air.
S.No.
1.
Characteristics
Fineness
Residue on 150- m IS sieve, % by mass, max.
2.
3.
Loss on drying, % vt mass, max.
Bulk density, g/ml
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Requirement
0.1
1.0
As agreed to between the
purchaser and supplier
Calcium carbonate (as CaCO3), % by mass 98.0
(on dry basis), min.
*Magnesium and alkali salts, % by mass
1.0 max
Aluminium, iron, phosphates and matter 0.5 max.
insoluble in hydrochloric acid, % by mass
Iron (as Fe), % by mass, max.
0.03
Arsenic (as As2O3), parts per million, max.
2
Heavy metals (as Pb), parts/million, max.
10
Chlorides (as Cl), % by mass, max.
0.04
pH of 10% aqueous suspension
9.0 to 10.0
Barium To pass test
Sulphates To pass test
*Flow point
As agreed to between the
purchaser and the supplier
Explosive and Pyrotechnic industry
IS specification for Calcium carbonate for Explosive and Pyrotechnic industry
IS: 7633-1982
Types
The material shall be of the following two types:
Type I
Type II
Calcium carbonate, natural
Calcium carbonate, precipitated
Description: Type I of the material shall be in the form of powdered calcite or limestone.
It shall be white to off-white in colour. Type II of the material shall be in the form of
white powder.
The material shall be free from extraneous matter and grit.
Requirements for Calcium Carbonate for explosive and pyrotechnic industry:S.No.
Characteristics
Requirement of
Type I
Type II
Loss on drying, % by mass, max.
0.05
0.5
Calcium carbonate (CaCO3) (on dry basis), % by 98.0
98.0
mass, min.
Matter insoluble in dilute Hydrochloric acid % 0.6
0.2
by mass, min.
Fineness (material retained on 125-micron* IS Nil
Nil
sieve) % by mass
Water insoluble alkali(as Na2O)% by mass.,max 0.03
0.05
Grit, % by mass, max.
0.06
0.02
Chlorides (as Cl), % by mass. max.
0.05
0.04
Total water soluble matter, % by mass, max.
0.05
0.5
i.
ii
iii
iv.
v.
vi.
vii
viii
* 90 micron for material required for use in propellants
Additional requirements for Calcium Carbonate for use in propellants.
S.No.
Characteristics
Requirement of
Type I
Type II
Magnesium compounds (as MgCO3), % by 0.5
0.5
mass. max
Iron (as Fe), % by mass, max.
0.05
0.05
Settling test (volume occupied by 5g), ml.
4 to 10
4 to 6
i.
ii.
iii.
2.
PRODUCT APPLICATIONS
Plastics
As a filler in rigid and plasticized PVC to improve impact strength.
As a filler in PVC footwear and cable compounds/cables to improve surface gloss and
other physical properties
As a filler in leather cloth sheetings
Paints and surface coatings
In emulsion paints as a white opacifying agent.
As an antisettling agent in paints and printing inks as an extender assisting in the control
of strength and body of the ink.
As a polishing agent in window and mirror cleaners and polishes.
In powder coatings
Cosmetics/tooth paste
In talcum powder, Calcium Carbonate is used to increase fluffiness and control
absorption characteristics.
In depilatory creams.
In face powders as a perfume carrier.
In sunscreen preparations.
Paper
In paper coating for brightness, smoothness, opacity and ink receptivity.
In cigarette paper for control of opacity and burning rate.
As a cost-effective filler in alkaline sized papers giving high brightness and opacity.
Food and Pharmaceuticals
Pharmaceutical:
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As a calcium source
As an antacid
As a neutralisation and filtration aid in antibiotic manufacture
As a buffering and dissolution aid in soluble tablets.
As a bulking agent in tableting
Food and Beverages

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As a calcium supplement
In effervescent powder drinks
In chewing gum
To neutralise excess acid in food and wine manufacture
As a filtration aid.
Putty, Caulks and Sealants
In PVC plastisols as a rheology modifier, particularly for car underbody.
Sealant applications on polyurethane, polysulphide and silicone.
Sealants for construction and insulation glass applications, as rheology modifier giving
slump control.
Significance of the applications
Calcium carbonate is used as fillers in the above joint fillers.
Caulks and sealants require less Calcium carbonate than putty due to their lower
viscosity.
Other miscellaneous sectors of application
Printing inks - filler
Joint cement compounds
Flue gas desulphurisation - Calcium Carbonate traps the sulfur oxygen compounds
produced in the combustion of coal.
In Insecticides
In polishes, shoe dressings
As filler in matches, pencils, crayons etc.
In linoleum, insulating compounds, welding rods
For water analysis and in preparing Calcium carbonate solutions for standardising soap
solutions.
3.
IMPORTS
Around 4000 tonnes per annum
4.
EXPORTS
Around 9500 tonnes per annum
5.
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INDIAN MANUFACTURERS
Annapurna Apex Chemicals (P) Ltd., Andhra Pradesh
Beautify Products, Gujarat
Citurgia Bio Chemicals Ltd., Gujarat
Kotak Chemicals Ltd.,Gujarat
Kalpana Chemicals, Gujarat
20 Microns Limited, Gujarat
Microfill Sharda Realtors Pvt. Ltd., Gujarat
Sukkan Industries, Gujarat
The Hindustan Mineral Products Pvt. Ltd., Gujarat
Bio Chemicals Ltd. Gujarat
Amgeen Aromatics, Gujarat
Dinesh Chandra Industries, Gujarat
Balco Chemicals, Gujarat
Indimin Sales Corporation, Gujarat
Kalpana Minerals Pvt. Ltd., Maharashtra
Cal Chem, Maharashtra
Calchem Industries (India) Ltd., Maharashtra
Darsynth Chemical Industries Pvt. Ltd., Maharashtra
Famous Minerals And Chemicals Co. Maharashtra
Gulshan Sugars & Chemicals Ltd. Maharashtra
Jaimurthi Minerals & Chemicals Pvt Ltd., Maharashtra
Ramdev Chem, Maharashtra
Sturdia Chemicals Ltd., Maharashtra
Vineeth Chemicals, Maharashtra
The Hindustan Mineral Products Co. Ltd.,
Chandroday Chemical Lime Inds. P.Ltd., Maharashtra
Harishit Chemicals, Maharashtra
Corrogard Chemicals, Maharashtra
Jagrut Chemicals, Maharashtra
Rashtriya Chemicals & Fertilizers Ltd., Maharashtra
Aranthangi Chemicals (P) Ltd., Tamil Nadu
Elf Atochem Peroxides India Ltd., Tamil Nadu
Ennor Muds & Chemicals, Tamil Nadu
Indian Chemicals & Minerals, Tamil Nadu
K.K. Carbonates Pvt. Ltd., Tamil Nadu
Merel Labs Pvt. Ltd., Tamil Nadu
Kor Chemicals P.Ltd., Tamil Nadu
Lime Chemicals Ltd., Himachal Pradesh
Trikuta Chemicals Pvt. Ltd., Jammu & Kashmir
Chemicals India, Rajasthan
SBR Singhania Chemical Industries, Uttar Pradesh
Rakehs Chemicals (P) Ltd., Uttar Pradesh
 U.P. Lime Chemicals Ltd., Uttar Pradesh
 Searsole Chemicals Ltd., West Bengal
Around 1,75,000 tonnes
per annum
Indian installed
capacity
6.
DEMAND SUPPLY TRENDS
Precipitated Calcium carbonate
84820
Activated calcium carbonate
23500
Total
108220
7.
MANUFACTURING PROCESS AND TECHNOLOGY DEVELOPMENT
Precipitated calcium carbonate is manufactured by calcining limestone and recarbonating
the hydrated slaked lime in vertical carbonation towers.
The reaction is exothermic and proper temperature control is maintained to get desired
quality of the product.
Technology developments
Technology based on Crystal Morphology:A new technology based on Crystal Morphology of Precipitated Calcium carbonate
(PCC) have been developed by Mineral Technologies, USA.
Minerals Technologies, a company based in New York city has developed recently a
patented PCC technology based on the manipulation of PCC crystal morphology.
Minerals Technologies has a long experience in operating limestone and take mines,
manufacturing mineral based furnace linings and producing PCC.
The company has patented technology allowing for the reaction of water, limestone and
carbon dioxide to produce a synthetic PCC. The company now produces the mineral in a
variety of particle sizes from 0.01 to 100 um and shapes from spherical to scalenohidral
and rhombhohedral.
The company now offers 12 different types of PCC. This synthetic PCC has found many
applications in industry. It has lowered the cost of manufacturing fine printing and
writing paper. Specially engineered PCC crystals displace more expensive wood pulp and
titanium dioxide and offer varying levels of gloss, light scattering or paper filling
properties. Current trends in paper business in USA seem to favour increasing use of
PCC.
Acid Tolerant Technology
The R&D of Mineral Technologies has led to the development of an acid tolerant PCC.
This breakthrough could extend PCC into the market for newsprint, directory, magazine
and catalog grade papers. Acid tolerant PCC opens a new paper market for PC. The new
acid tolerant PCC provides a way to improve the brightness and quality of newsprint.
Certain grades of PCC offer such good light scattering ability that they serve an
additional benefit of replacing TiO2 in fine paper making. As PCC is much cheaper in
price than TiO2, the advantage of replacing TiO2 with PCC is obvious economically.
Minerals Technologies R&D has developed yet another process to produce PCC that
could further endear the company to its paper industry customers. Its lime soda process
yields byproduct caustic soda. In this process, soda ash can replace the carbon dioxide the
company now gets from its mill host.
Minerals Technologies has signed agreements with two paper companies to provide
Precipitated Calcium carbonate (PCC) using its acid- tolerant technology at three ground
wood paper mills in North America.
8.
GLOBAL SCENARIO
Global consumption pattern of Precipitated calcium carbonate
Industry
Paper
Paints
Plastics
Rubber
Food,
cosmetics
pharmaceuticals
Textile packing
Putties, caulks, sealants
Adhesives
Printing ink
Consumption in
%
72
8
5
4.5
and 4
2.5
2.5
1
0.5
Thrust Area for Demand in the Global Market
In developed countries, the paper industry is the largest consumer of Calcium carbonate,
as a filler and in coatings. Coarser particle size grades (over 2 micron) are used as fillers,
where alkaline pigment with low water demand is preferred. Most of the Precipitated
Calcium carbonate go into paper coatings alone or in conjunction with clay. In this
application, Precipitated Calcium carbonate adds brightness, opacity and better printing
ink receptivity.
In developed countries, next to paper industry, paint industry is second in consumption of
Calcium carbonate. They are widely used both in alkyd and latex flat wall paints. These
grades provide uniform floating, as well as good colour and uniformity on recoat and
overlap.
The plastic industry uses Precipitated Calcium carbonate in different areas. Precipitated
Calcium carbonate also finds wide use in other thermosetting plastic compounds.
The printing ink industry uses the ultrafine Precipitated Calcium carbonate in high quality
letter press and high quality ink.
Caulks and sealants especially the higher quality elastomeric types are especially
formulated with Precipitated Calcium carbonate as semi reinforcing filler types.
Rubber compounding consumes a considerable amount of ultrafine Precipitated Calcium
carbonate for use as reinforcing fillers.
The miscellaneous end use areas are in foods and pharmaceuticals. Calcium carbonate are
approved by the Foods and Drug Administration of USA, primarily for Calcium
enrichment for chewing gum based and for cherry brining.
9.
RECOMMENDATIONS
Calcium Carbonate industry is of particular relevance to Indian conditions, in view of the
adequate availability of raw material namely Lime Stone in the country and also the fact
that the economic capacity of Calcium Carbonate and the project cost would not be high.
This would make it possible to implement the project in medium scale sector.
With regard to the cost of production, fuel and energy factors are important and such
energy factors have to be maintained at competitive level.
With regard to the quality of the product, international companies produce products in
various grades catering to the requirements of individual user sector like PVC, Paper etc.
Indian units are yet to make large number of grades of products, for meeting the specific
requirements of end users.
In the case of cosmetic industry, there appears to be particular preference for micronised
calcium carbonate, in view of its higher surface area.
In considering the Calcium Carbonate project, the factors that should be considered are
the following.
*
Proximity to the source of good quality limestone. Most of the Calcium Carbonate
units have been located near the limestone deposits.
*
The operating parameters of the project from the point of view of the energy
requirements have to be carefully studied.
*
Considering the fact that the consumers of Calcium Carbonate like toothpaste
would opt for good quality of the product even without consideration for marginal
increase in price, ensuring adequate quality would significantly help the project in the
competitive market.
*
It is necessary to avoid putting up small size plant, since it would make it difficult
to introduce adequate energy and quality management techniques in small plants.
*
The scope for optimisation of the quality and energy management and also the
growth rate in demand would justify a plant of large capacity.
In view of the abundant availability of Limestone deposit in Tamil Nadu, Calcium
carbonate project can be favourably considered.
Recommended capacity
1500 tonnes per annum
Estimated project cost
Rs.12 crores