As we all know, the air pollution norms are getting stricter with every day passing by. So it becomes quite obvious to install and commission an air pollution control device. One such air pollution control equipment is the Bag Filter. Bag Filter helps in separating the particulate matter from the flue gas coming out of the Steam Boiler. Most common type of Bag Filter is Pulse jet type.
Pulse jet bag filter operation
Bag filter comprises an arrangement of Bags, made up of special fabric, capable of bearing the operating temperature of up to 220 degree Celsius. These bags are long, vertically fit up on a ring like structure. This structure provides rigidity to the bags when inserted inside them, now every bag is arranged vertically in row/column fashion.
The design of Bag Filter heavily relies on the Air to Cloth Ratio as per the composition (type of fuel used) and flow of flue gases. It is installed such its outlet is the id fan flue gas inlet. Flue gas coming out of the Boiler, travelling through the duct, enters the casing of the bag filter, so because of suction created by the ID Fan, the flue gases come in contact with the bags and enters the hollow portion because of pressure gradients. During this, the heavy particles get collected on the bag’s external surface because of its impermeability to them. The filtered flue gases then enter a separate chamber from the bag’s outlet and get supplied to id fan inlet and then to chimney to be released into the atmosphere. With time, the dust content on the bag’s surface goes above the desired level, in that case, the pulse jet system comes in action by supplying pressurized air. This air enters the bags through its flue gas outlet and shakes up the bag, so the dust is at rest gets separated from the bags (basic inertia concept) and gets collected at the bottom of the equipment.
The frequency of this pulse jet cleaning depends upon the dust percentage in the flue gas.
We at Thermodyne Boilers, have supplied and commissioned Bag filter to many of our clients successfully.
- Reduced levels of Particulate emissions.
- Easy to operate and maintain.