What the fans do here
Coal handling plants raise dust at every crusher, screen and transfer point. Dust extraction fans draw the air into bag filters and cyclones, and the whole system is built spark resistant. Seal air blowers on the mills keep coal dust out of the bearings.
Applications in this industry
| Application | What it does | Type usually selected |
|---|---|---|
| Dust Collector Fan | The fan behind a bag filter, cyclone or multiclone on a dust extraction system. Placed on the clean side where possible so the blade can be chosen for efficiency. | Backward inclined and radial tipped |
| Seal Air Blower | Supplies clean air at a pressure above the mill or fan casing pressure to the shaft seals and bearing housings, so pulverised coal cannot enter. | Backward curved and radial |
| Coal Mill Fan | Draws hot gas through the coal mill to dry and convey the pulverised coal to the burner or the fine coal bin. Built spark resistant because the gas carries combustible dust. | Backward curved and radial tipped |
Processes in this industry
Equipment supplied
Centrifugal Fans
0.3 to 120 m³/s, 25 to 3120 mmWC single stage. Six blade configurations, three drive arrangements.
Bag Filter
Fabric filters in polyester, polypropylene, Ryton and Nomex. Efficiency to 99.9% down to 5 micron.
Cyclonic Separator
Coarse dust pre-collector. Low cost, low maintenance, low pressure drop. To 90% down to 30 micron.
Multiclone
Bank of small cyclones in one housing. To 90% down to 20 micron, with hopper and rotary air lock.
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.