Vent Silencer for Captive Power Plants

The process

Captive power plants at process industries run AFBC, CFBC or grate boilers on coal, lignite, husk or bagasse. The fan set is the boiler fan set, sized for the fuel and for a plant that cannot afford a stop.

The gas at the fan

Fluidised bed combustion carries bed material fines and fly ash in the flue gas. The dust is abrasive and the loading ahead of the collector is high, so the ID fan is placed after the dust collector wherever the layout allows.

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 160°C the gas density is close to 0.81 kg/m³, 68% 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.

Cuts the noise from steam or gas expanding from high pressure to atmosphere at safety valve outlets, start-up vents and blow-down lines. Client-stated blade types for the Vent Silencer in general: Silencer.

Industries

Other fans in captive power plants

Vent Silencer in other processes

Information needed to select or quote

1. Gas volume and temperature. Actual flow at the inlet, normal and upset temperature, moisture.
2. Dust or pollutant. Inlet loading, particle size distribution, whether it is abrasive, sticky, hygroscopic or combustible; for gases, the species and concentration.
3. Required outlet. The emission limit or clean gas concentration the unit must meet.
4. Site. Available space and height, material of construction preferences, and how the collected material is to be discharged.