The process
Carbon black reactors, quench and main bag filters handle the product itself as a fine, adhesive dust. The main process fan after the bag filter and the dryer and conveying fans all need sealing against the dust.
The gas at the fan
Carbon black is extremely fine, adhesive and penetrating. The fan is on the clean side of a bag filter, with seals that keep the dust out of bearings and a wheel that can be cleaned.
Selection for this duty
| Blade form | Straight radial, open or shrouded, so the wheel can be cleaned and does not hold deposit |
| Material of construction | Mild steel |
| Drive and bearings | Direct coupled or belt driven; belt drive where the duty point may need tuning at site |
| Also specified | Access doors on the scroll and a wheel that can be cleaned in place |
| Density at the fan | At about 60°C the gas density is close to 1.06 kg/m³, 88% of standard air. Pressure developed and power drawn fall in the same ratio, so the selection is made at this density and the motor is checked at cold start. |
Sits at the outlet of a boiler, kiln or furnace and draws the flue gas through the plant to the stack. It handles hot, dust-laden gas at large volume, so it is sized at the hot condition and checked at cold start. Client-stated blade types for the ID Fan in general: Backward curved, backward inclined and radial tipped.
Industries
Other fans in carbon black plants
ID Fan in other processes
Services on this fan
Information needed to select or quote
- Duty point. Volume flow and static pressure at the fan inlet, with the gas density and temperature or the conditions to derive it.
- Operating conditions. Site altitude, normal operating temperature and continuous or intermittent duty.
- Gas stream. Dust loading and particle size, corrosive species, moisture, upset temperature and any tendency of the material to deposit on the impeller.
- Mechanical. Rotation viewed from the drive end, discharge orientation and motor power.
