Induced Draft Fans And Their Applications

By Author: Neel Rao
Total Articles: 131
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What Are Induced Draft Fans?
Industrial induced draft fans are used mostly as a means to extract exhaust air from boilers. They usually focus on utilising differences in pressure and volume. In some cases, they are used together with forced draft fans, which helps to maintain a relatively low system air pressure steadily.

What Is An Induced Draft?
The difference between the pressure within the furnace or flue gas passage in a boiler system and the atmospheric pressure is commonly termed as a draft. Decreasing the system pressure below ambient pressure affects the flow of air and flue gas. This is known as an induced draft.

Induced draft fans are located between the chimney and the dust collector. It basically collects the hot flue gases and delivers them to the chimney. In large boilers, ID fans are also used to identify the combustion process being used.

ID fans regulate the air pressure within boilers and other systems and suck out discharged air through blowers. They also supply the boilers with the air necessary for the combustion process. This ensures the smooth running of the entire combustion ...
... process.

In steam power plants, ID fans and FD fans are used together to generate electricity through the combustion of fossil fuels. There these fans create a gradient of pressure known as draught. This gradient expels the burnt gasses out and sucks fresh air into the boiler. Several boiler accessories are located in between the chimney and the boiler. These help to make the power plant more efficient.

The ID fans are usually located at the base of chimneys. From there, they maintain low pressure in the boiler and the accessories. The low pressure helps to suck fresh air into the boiler and the accessories. They also drive burnt gases out of the chimney by maintaining high pressure.

Application Of ID Fans
Let us take a look at a brief overview of the applications of ID fans:

• They are large in size and exhaust primary as well as secondary air.
• They are used to expel gases into the atmosphere.
• To reduce the risk of explosion due to the pressurisation of the boiler, they create a balanced draft which helps to maintain negative pressure.

Basically, the job of an ID fan is to suck air through a system by creating negative pressure. Induced draft fans used in boilers must be capable of handling high particulate loadings and hot gases. The food processing industry witnesses considerable application of ID fans. There these fans help in cleaning the system of cooking odours. Other applications of these fans include ventilation and combustion processes.

In the industrial processes, ID fans get exposed to various harsh conditions. The air they process often include extremely hot gases, acidic streams of air, and other corrosive elements. While the ID fans are crucial to keep your system clean of these elements, they also pose a threat to the health of the fans.

Induced Draft Fans - Usage And Common Applications
The induced draft fans are used mostly in power plants, steel plants, cement plants, and the food processing industry. The most common applications are conveying raw materials and gasses. Almost any industrial process which involves the movement of air requires ID fans. These fans are used to handle a wide variety of materials in various industries and need to be manufactured accordingly. Evidently, induced draft fans are a key component in the respective industries.

Reitz India is a leading manufacturer and supplier of premium Centrifugal Fans that find wide usage in heavy industrial applications. Reitz India has incorporated latest technology in FD Fan and ID Fan design and fabrication to provide energy efficient and cost effective solutions with high industrial standards.