The process
Smelting and roasting of sulphide concentrates gives hot, dusty gas with sulphur dioxide. Gas cleaning ahead of the acid plant uses cyclones, ESPs and scrubbers, and the fans between them handle acidic, abrasive gas in resistant materials.
The gas at the fan
Sinter strand waste gas carries ore and flux fines with acid components from the sulphur in the fuel. Wear and corrosion both act on the wheel; material and liner selection follow the gas analysis.
Selection for this duty
| Blade form | Radial tipped with wear liners, or straight radial where the dust is coarse |
| Material of construction | Stainless steel on all wetted parts, grade to suit the gas analysis |
| Drive and bearings | Direct coupled or belt driven with a shaft cooling disc and bearings outside the casing |
| Also specified | Hard facing or liners on the blade pressure face |
| Density at the fan | At about 150°C the gas density is close to 0.83 kg/m³, 69% 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. |
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. Client-stated blade types for the Fume Exhaust System in general: Backward inclined and radial tipped.
Industries
Other fans in copper and zinc smelting
Fume Exhaust System in other processes
Coke Oven BatteriesElectric Arc Furnace SteelmakingInduction Furnace Melt ShopsLadle Furnaces and Secondary MetallurgyForge ShopsFerro Alloy Submerged Arc FurnacesAluminium Smelters and Cast HousesIron and Non-ferrous FoundriesHot Dip Galvanising LinesChemical Reactor and Tank VentsEffluent Treatment and Zero Liquid Discharge PlantsSolvent Recovery PlantsFertilizer Granulation PlantsSulphuric Acid PlantsFood Ovens and FryersPaper Machine Dryer SectionsPulp Mills and Recovery BoilersTextile Stenters and DryersDyeing and Finishing HousesAutomotive Paint ShopsPickling and Acid Treatment LinesWelding and Fabrication ShopsTyre Curing PressesShipyard Hull and Block Fabrication
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.