Atmospheric cleaning bag filter

The atmospheric cleaning bag filter, also known as the filter dust collector, is a dry dust collector that uses bag filter elements made of fiber woven fabric to capture solid particles in dusty gases.

The atmospheric cleaning bag filter consists of inlet and outlet flues, dust removal chamber, clean air chamber, cleaning system, and ash hopper. During the operation of the atmospheric cleaning bag filter, the exhaust gas temperature drops to 130 ℃, and the dust containing gas that can instantly reach 180 ℃ is distributed through the lower flue of the bag filter and enters the ash hoppers in each chamber. Due to factors such as flow deflection and reduced velocity, the flue gas causes coarse and heavy dust particles to settle, achieving the purpose of pre separation. Fine dust enters the dust removal chamber of the offline pulse dust collector by turning upwards with the airflow. Due to the filtering effect of the offline pulse dust collector filter bag, the dust is trapped on the outer surface of the filter bag. After filtration, the clean gas enters the clean air chamber of each unit from the inside of the filter bag of the offline pulse dust collector and converges in the outlet flue. After passing through the induced draft fan, it is discharged into the atmosphere through the chimney.

The atmospheric cleaning bag filter solves the problem of "dust reattachment and loss of control" that exists in conventional pulse bag filters, greatly improving the cleaning effect of the filter bag and thus increasing the filtration speed. It not only saves cleaning energy but also extends the service life of the dust removal filter bag.

The atmospheric dust bag filter adopts the technology of high-pressure (0.5-0.7Mpa) flow pulse valve to blow and clean the dust filter bags one by one. It can collect a large amount of dust (particles ≤ 5 μ m, content ≥ 70%) from the gas, with an emission concentration of less than 60mg/Nm3. It is widely used in dust control in the cement industry and has good application prospects in industries such as chemical, metallurgical, steel, and power. The dust collector body adopts a fully steel structure design, and the external customers use LBY type lightweight rock wool board double-layer insulation. Cold press forming process for flower boards not only increases strength but also improves equipment quality. Choose different filter media and their filtration speed according to the working environment.

The atmospheric dust bag filter adopts high-frequency vibration and reverse blowing. The reverse blowing is achieved by a designed electric cylinder driving a three-way valve, and the action of the electric cylinder is controlled by a set of automatic control system. Compared with the pulse reverse blowing and high-pressure reverse blowing bag filters used in the past, it saves investment in supporting auxiliary equipment and significantly reduces electricity consumption and equipment operating costs. At the same time, it also has the advantages of stable performance, easy dust removal and maintenance, and long filter bag life.

Working principle of atmospheric dust bag filter:

The dusty gas enters the ash hopper through the inlet pipe, and is purified by the filter bag inside the box. It is then discharged to the outlet pipe through the main valve plate opened by the electric three-way valve. The gas in the outlet pipe is then discharged into the atmosphere through the centrifugal fan and chimney.

As the working time increases, the thickness of the dust layer on the inner wall of the filter bag gradually increases, and the resistance also gradually increases. When the resistance increases to 80-120 millimeters of water column (as can be seen by the U-shaped pressure gauge), the electric cylinder starts and the main valve plate of the electric three-way valve is closed, and the auxiliary valve plate is opened for reverse blowing and dust cleaning.

After the blowback air enters the box through the electric three-way valve, it passes through the filter bag in the opposite direction compared to the filtered state. At the same time, the high-frequency electric vibrator starts to operate, causing the filter bag to vibrate at high frequencies. Under the simultaneous action of blowback and high-frequency vibration, it has the effect of cleaning dust (the cleaning time is adjustable). When the dust cleaning is completed, the high-frequency electric vibration stops vibrating. The main valve plate of the electric three-way valve is opened, and the auxiliary valve is closed at the same time, restoring the normal filtering state. The adjacent interval time for cleaning can be adjusted as needed to ensure that each box is cleaned in the specified time sequence.

The cleaning system of the atmospheric dust bag filter adopts high-frequency vibration and reverse air blowing. The reverse air blowing is achieved by a designed electric motor driving a three-way valve, and the action of the electric cylinder is controlled by a set of automatic control system.

Atmospheric dust bag filters are widely used in industries such as building materials, ceramics, metallurgy, grain, chemical, casting, and light industry.

Characteristics of atmospheric dust bag filter:

l、 The atmospheric cleaning bag filter is particularly suitable for air purification of light, fine, and viscous dust.

2. The atmospheric cleaning bag filter adopts a submerged pulse valve, with a small negative force in the flow channel and a gas source pressure ranging from the conventional 0.5MPa to 0.3MPa

3. Due to offline blowing for dust cleaning, the cleaning cycle has been extended from the conventional 3-5 minutes to 20-30 minutes. As a result, the energy consumption for dust cleaning has been reduced, and the pressure consumption is only about one of the conventional types. At the same time, the fatigue and wear of the filter bag and pulse valve diaphragm have also been correspondingly reduced, thereby doubling the service life of the filter bag and valve disc.

4. The filter bag mouth adopts a spring expansion ring, which has good sealing performance and is firm.

5. The atmospheric cleaning bag filter adopts the upper bag extraction method. When changing the bag, after extracting the dust removal skeleton, the dirty bag is put into the lower ash door of the box and taken out through the inlet hole. The bag replacement operation strip is used.

6. The layout of the import and export collection pipes is compact, with low airflow resistance.