The process
The grate cooler takes clinker at over a thousand degrees and quenches it with air blown up through the grate by a row of compartment fans, each at its own pressure. The hot air not needed for combustion is exhausted by the cooler vent or cooler ID fan through an ESP or bag filter.
The gas at the fan
Surplus cooler air carrying clinker dust, hot and abrasive. Temperature swings with kiln operation, so the fan is selected across the band rather than at one point.
Selection for this duty
| Blade form | Radial tipped, or backward inclined where the fan sits after the collector |
| Material of construction | Mild steel with replaceable wear liners on the blades and the scroll at the cut-off |
| Drive and bearings | Direct coupled, shaft cooling disc, bearings in a pedestal outside the gas stream, allowance for thermal growth |
| Also specified | Hard facing or liners on the blade pressure face |
| Density at the fan | At about 250°C the gas density is close to 0.67 kg/m³, 56% 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. |
Blows ambient air up through the grate of the clinker cooler. Each compartment has its own fan set for the pressure that bed needs. Client-stated blade types for the Cooler Compartment Fan in general: Backward curved and radial tipped.
Industries
Other fans in clinker grate coolers
Cooler Compartment Fan in other processes
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.