What the fans do here
Pig iron and steel plants need fans for the blast furnace stove, the sinter plant, the coke oven and the fume extraction over converters and electric arc furnaces. Combustion air blowers feed the stoves and reheating furnaces. Fume exhaust fans handle hot, dust-laden gas from the melt shop into bag filters. ID fans on the sinter strand and the boiler are built for abrasive dust and high temperature.
Applications in this industry
| Application | What it does | Type usually selected |
|---|---|---|
| ID Fan | 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. | Backward curved, backward inclined and radial tipped |
| FD Fan | Supplies combustion air to a boiler or furnace, pushing ambient air through the air heater and into the windbox against the furnace draft. Clean air, so the blade is chosen for efficiency. | Backward curved and backward inclined |
| Combustion Air Blower | Feeds a burner with air at the pressure the burner register needs. Sized for the burner turndown range, and often fitted with an inlet silencer. | Backward curved and radial tipped |
| Fume Exhaust System | Hoods, ducting and an exhaust fan that capture fume at source and deliver it to a scrubber, bag filter or stack. Fan material follows the fume: stainless steel, PP-FRP or rubber lined where it is corrosive. | Backward inclined and radial tipped |
| 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 |
| Hot Air Fan | Circulates or supplies air at elevated temperature to a dryer, oven or kiln. Selected at the hot density with the shaft and bearing arrangement built for continuous hot running. | Backward curved and backward inclined |
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.
Wet Scrubber
Static, spray tower, packed bed, venturi and cyclonic spray types. 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.
Dampers
Butterfly, multi louver, inlet vane, diverter and guillotine dampers in MS and stainless steel.
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.