Carbon black is produced by the thermal decomposition and pyrolysis of low-value oil residues at high temperatures under controlled conditions.
At Birla Carbon, we produce carbon black in a high-temperature reactor through a tightly controlled flame-synthesis process that uses carbon-rich oil residue, and sometimes natural gas, as feedstock. Our carbon black has real value; the oil residue used in its production has limited usage and would otherwise be thrown away.
Watch our video to learn how carbon black is made.
1. Feedstock oil
To begin the process, preheated air and oil (and sometimes natural gas) are fed to the reactor in tightly controlled amounts.
Inside the reactor, the air and hydrocarbons undergo a complex set of reactions – partial combustion, thermal decomposition, particle nucleation and particle growth/aggregation. These reactions occur in temperatures up to 1,800 degrees Celsius and can take less than one hundredth of a second.
3. Water injection
Water is then injected to stop the reactions by reducing the temperature of the carbon black “smoke” stream leaving the reactor.
This “smoke” stream is then routed to a baghouse that separates the carbon black from the reactor tail gas using hundreds of fabric filter bags. The carbon black is a light, fluffy powder as it exits the baghouse and is transported to an accumulator tank.
5. Pellet formation
The carbon black powder is mixed with a binding agent and water in a pelletizer to form pellets, which are then dried in a rotary drier. This process increases its bulk density by up to five times, allowing for more efficient transportation to our customers.
6. Storage and packaging
In the final step, the carbon black pellets are packaged in a variety of containers, ranging from 10-kg paper bags to 60-tonne railroad cars, for transportation to our customers.