Air box pulse bag filter is composed of box body, bag room, ash hopper, air inlet and air outlet, and is equipped with pillars, ladders, railings, air path system, ash cleaning controller, etc.
1), box The box is mainly used to fix the bag cage, filter bag and air passage parts, and made into a fully enclosed form. When cleaning ash, compressed air first enters the box and rushes into the interior of each filter bag. There is an access door at the top for installing and replacing the bag cage and filter bag. The box is divided into several rooms, which are separated by steel plates and sealed with each other to realize off-line dust removal. Each room is equipped with a lift valve to open and close the filtered dust airflow.
2) Ash hopper The ash hopper is arranged at the lower part of the box, which is used as the main air inlet besides storing the collected dust. The dusty gas enters the ash hopper before entering the bag filter chamber. Due to the large volume of the ash hopper, the airflow speed decreases, and the coarse dust particles are separated here due to the change of airflow direction. The ash hopper is equipped with conveying equipment such as screw conveyor or air duct, and the outlet is also equipped with wind locking equipment such as rotary unloader or flap valve, which can continuously exhaust air.
Working principle of air box pulse bag filter: When dusty gas enters the dust hopper from the air inlet, due to inertial collision, natural settlement and other reasons, part of coarse dust particles fall into the dust hopper, and most dust particles rise with the air flow and enter the bag chamber. After being filtered by the filter bag, the dust particles remain outside the filter bag, and the purified gas enters the box body from the inside of the filter bag, and then is discharged from the air outlet to achieve the purpose of dust collection. With the progress of filtration, the dust accumulated on the outside of the filter bag gradually increases, so the movement resistance of the dust collector gradually increases. When the resistance reaches the preset value, the ash cleaning controller sends a signal, first controls the poppet valve to close the valve plate hole, thus cutting off the airflow of filtering dust, stopping the filtering process, and then opens the electromagnetic pulse valve. In a very short time (0. 1-0. 15S), compressed air with a pressure of 0.4-0.6MPa is injected into the box, and the compressed air expands rapidly in the box and fills the south of the filter bag, resulting in deformation and vibration of the filter bag. Under the action of reverse airflow, the dust outside the filter bag is taken away and falls into the ash hopper. After the dust removal, open the lift valve again, and the dust will enter the filtering state again.