| 1. What is the history of Carbon Black? |
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The earliest form of carbon was perhaps made as lamp black and used by
Egyptians, Indians, Chinese and for writing, painting and as cosmetic.
Even today in old homes in India Mascara is home made. This then became
the "Lamp Black". Then followed the manufacture of "Channel black" where
small gas burners and the soot was allowed to deposit on a steel "Channel"
deriving its name from this method of manufacture.
"Thermal black" was manufactured by passing the natural gas over a heated
Refractory checker works until the temperature dropped down. At this
point the path of the gas is changed to another heated checker work, which
is kept ready for production. Present method is a continuous process in
specially designed furnaces called the "Reactors"
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| 2. What is the Product of ACB Company known as? |
| Rubber Grade Oil Furnace Black.
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| 3. What is Carbon Black? |
| Carbon Black essentially elemental carbon
in the form of fine particles having a semi-graphitic structure in the form
of randomly oriented condensed rings loosely held and with open edges having
unsatisfied carbon bonds providing sites for chemical activity. Along with
these sites are also hydroxyl and carboxyl ions and sulphur in functional
groups and small quantities of condensed hydrocarbons are adsorbed on the
surface of the carbon black. All of these provide the surface activity required
for interacting with Rubber. |
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| 4. How are Carbon Blacks Produced? |
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Carbon Black is produced by incomplete combustion of aromatic oils. The
incomplete combustion is achieved in the reactors in a continuous process
in specially designed furnaces called the "Reactors". It is in the form
of "Smoke" as in a very bad flare. The conversion mechanism is a combination
of pyrolysis and regrouping of the particles to form "Aggragates". The
desired charateristics are achived by quenching with water in controlled
quantities at predetermined locations in the reactor.
The smoke is the admitted into a Bagfilter containing fiterbags made
of glass fiber and specially treated. Here the carbon is seperated and
the effluent gas containing combustibles are piped into heat recovery
system.
The separated Carbon is conveyed to a pelletiser by suitable conveying
system and is pelletized to form small round globules with addition of
water and binder. The pelletized Black is then dried in a Rotary Drier.
The fuel used is the waste gases from the process which have combustibles
and very low in calorific value, burnt in a specially designed furnace.
The product is then stored in silos for suitable packaging and selling.
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| 5. What are the main characteristics of Carbon Black? |
| Carbon Blacks are charaterized by their "Particle Size
or Surface Area per Unit weight" and "Structure". Depending on these It derives
its ASTM designated numbers. |
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| 6. What is it's Structure? |
| It is the second most important property of carbon black.
It is most strongly related to the degree of clustering or bonding of the
primary particles. |
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| 7. How is the structure of Carbon Black measured? |
| It is measured by the absorption of Di-Butyl Phthalate
(DBP)oil by the Carbon Black. It is estimated by mixing DBP oil in a specially
designed bowl equipped with rotors in which oil is added slowly to the carbon
black until a preset torque is reached. The machine cuts off at this point
and the oil added in milliliters per 100 gms of the sample is reported as
the DBP absorption Number. |
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| 8. What are the other significant Properties of Carbon black?
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| Aggragate size is the third fundamental property as
it influences performance in rubber. |
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| 9. How are those determined? |
| It is normally determined in production by the tinting
strength test. The test involves in mixing of carbon black with a large
quantity of Zinc oxide powder with a plasticizer and measuring the hiding
power of the black when tested for light reflectance. The more the hiding
power the more is the tinting strength. |
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