The process
Oil and gas fired boilers have clean flue gas and no dust collector, so the fan set reduces to an FD or combustion air fan and, on larger units, an ID fan. The duty is clean air or clean gas, selected for efficiency and quiet running, with a silencer on the FD inlet where the boiler house is near offices.
The gas at the fan
Clean air that has passed through an air heater or recuperator. Density is lower than ambient, so the fan is selected at the hot condition and checked for motor load at cold start.
Selection for this duty
| Construction | Absorptive annular design in mild steel; stainless steel where the gas is wet or corrosive |
| Density at the fan | At about 180°C the gas density is close to 0.78 kg/m³, 65% 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. |
An absorptive silencer at the fan inlet, outlet or in the duct, cutting fan noise with minimum pressure loss. Client-stated blade types for the Fan Silencer in general: Silencer.
Industries
Other fans in oil and gas fired boilers
Fan Silencer in other processes
Bagasse Fired BoilersRice Husk Fired BoilersAFBC BoilersCFBC BoilersPulverised Coal Fired BoilersWaste Heat Recovery BoilersBiomass Fired BoilersThermic Fluid HeatersBlast Furnace Hot Blast StovesSinter PlantsSteel Reheating FurnacesPharmaceutical Clean RoomsRefinery Fired HeatersFlare and Pressure Relief SystemsGas Compressor StationsCaptive Power PlantsGenerator and Engine RoomsCar Parks and TunnelsNuclear Facility VentilationHospitals and LaboratoriesData Centres and Equipment RoomsDistillery Spent Wash Incineration Boilers
Information needed to select or quote
- Gas volume and temperature. Actual flow at the inlet, normal and upset temperature, moisture.
- Dust or pollutant. Inlet loading, particle size distribution, whether it is abrasive, sticky, hygroscopic or combustible; for gases, the species and concentration.
- Required outlet. The emission limit or clean gas concentration the unit must meet.
- Site. Available space and height, material of construction preferences, and how the collected material is to be discharged.