What the fans do here
Ferro alloy, aluminium and copper plants run submerged arc and reverberatory furnaces whose fumes carry fine metallic dust and, in some processes, acid gas. Fume exhaust fans pull the furnace gas into bag filters or wet scrubbers, ID fans handle the boiler and dryer gas, and combustion air blowers serve the furnaces. Stainless steel or lined construction is common on the scrubber side.
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 |
| 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 |
| 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 |
| 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
Waste Heat Recovery BoilersInduction Furnace Melt ShopsFerro Alloy Submerged Arc FurnacesAluminium Smelters and Cast HousesCopper and Zinc SmeltingIron and Non-ferrous FoundriesSulphuric Acid PlantsLead Smelting and Battery Recycling
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.
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.