induced draft fan

induced draft fan

The function of induced draft fan is to discharge the waste gas produced by the combustion of pulverized coal in the boiler into the flue and then into the atmosphere through the chimney. It needs to overcome the resistance of the pipeline from the boiler outlet to the chimney outlet, including the resistance of the flue, air preheater, denitrification device, dust collector, desulfurization absorption tower, and chimney. It is widely used in coal-fired units, oil-fired units, circulating fluidized bed units, etc.

For 300MW and above boilers, most induced draft fans use dual-speed centrifugal fans with dual suction and inlet guide vanes for control, while some employ imported adjustable dampers.

The working principle of centrifugal induced draft fan is that the impeller rotates, and the impeller blades do work on the gas, converting the mechanical energy of the impeller into gas energy. The flow rate of centrifugal induced draft fan is suitable for the range of 80～1100 m3/s, and the pressure is suitable for the range of about 5000～15000 Pa.

The figure below shows the induced draft fan rotor assembly:

technological superiority ：

1. The centrifugal fan has a wide range of technical parameters and great applicability.

2. Advanced design, adopting a "tailor-made" approach to ensure optimal fit.

3. The fan features a flat curve and a wide high-efficiency range, with high operational efficiency, all meeting the national first-class energy efficiency standards.

4. Advanced anti-wear and anti-corrosion measures ensure safer and more reliable operation of the fan.

5. With multiple adjustment modes, it provides stepless, on-the-go, and frequent adjustments to meet diverse user needs.