In the carbon black industry, the application of expansion joints is mainly reflected in the energy saving and consumption reduction of carbon black production. Especially at the hot air line connection from the air preheater outlet to the reactor inlet, the expansion joint plays a key role.
Air preheater is one of the main heat exchange equipment in carbon black production. It can preheat the air required for production from 100℃ to about 800℃, and at the same time cool the carbon black flue gas from 950℃ to about 660℃. This preheating process not only increases the sensible heat value of the air, but also reduces the amount of fuel replenishment required during carbon black production, thus reducing the energy consumption for carbon black production. However, due to flue gas fluid temperature changes, the thermal expansion coefficients of reactors, hot air lines and other equipment may be inconsistent, which requires the installation of expansion joints at the air preheater outlet and the connection of hot air lines to the reactor.
The main function of the expansion joint is to absorb the length and dimension changes of pipes, containers and other equipment caused by temperature changes, thus eliminating thermal stress, reducing cold shrinkage, and avoiding noise or influence on the environment caused by pipe vibration. In carbon black production, this expansion joint can not only ensure the stable operation of the equipment, but also effectively reduce the heat loss, improve the heat insulation performance, further reduce the fuel replenishment amount, thus reducing the energy consumption of carbon black production.
Specifically to the structure design of the expansion joint, an energy-saving expansion joint for carbon black production adopts the design of bellows and gasket ring. The corrugated protrusion on the bellows and the inner lining structure in the bellows make the expansion energy saving greatly reduce the heat loss and improve the heat insulation performance under the premise of ensuring the existing expansion stress. At the same time, the gasket rings sleeved on both sides of the bellows form an interference fit with the bellows, which further enhances the performance of the expansion joint.
To sum up, the application of expansion joints in the carbon black industry is mainly to reduce heat loss and improve energy utilization efficiency by optimizing heat exchange and pipeline connection in the carbon black production process, thus realizing energy saving and consumption reduction in carbon black production.