The process
Tile, sanitaryware and tableware kilns run on gas with combustion air blowers, a kiln exhaust fan on the preheat zone, and hot air fans that recover cooling zone heat for the dryers. The exhaust carries fluorine and sulphur compounds from the body and glaze.
The gas at the fan
Kiln exhaust with light dust and fluorine or sulphur compounds from the body and glaze. Hot, mildly corrosive; stainless steel or coated construction on the wetted parts.
Selection for this duty
| Blade form | Backward inclined or backward curved; the residual dust does not justify a radial wheel |
| Material of construction | Stainless steel on all wetted parts, grade to suit the gas analysis |
| Drive and bearings | Direct coupled, shaft cooling disc, bearings in a pedestal outside the gas stream, allowance for thermal growth |
| 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. |
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. Client-stated blade types for the Combustion Air Blower in general: Backward curved and radial tipped.
Industries
Other fans in ceramic tunnel and roller kilns
Combustion Air Blower in other processes
Bagasse Fired BoilersRice Husk Fired BoilersAFBC BoilersCFBC BoilersPulverised Coal Fired BoilersOil and Gas Fired BoilersBiomass Fired BoilersThermic Fluid HeatersHot Air GeneratorsRotary Lime KilnsVertical Shaft Lime KilnsSponge Iron Rotary KilnsBlast Furnace Hot Blast StovesSinter PlantsCoke Oven BatteriesSteel Reheating FurnacesHeat Treatment FurnacesForge ShopsFerro Alloy Submerged Arc FurnacesAluminium Smelters and Cast HousesIron and Non-ferrous FoundriesHot Dip Galvanising LinesGlass Melting FurnacesCeramic Body Spray Dryers
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.