Boiler bag filter

Boiler bag filter is a commonly used supporting equipment in boilers and industrial production, mainly used for particulate smoke and dust emitted from boiler fuel and combustion processes. It can significantly reduce the amount of smoke and dust discharged into the atmosphere, and is a very environmentally friendly equipment for polluting the environment and improving air quality.

The boiler bag filter adopts domestic composite material fiberglass resin, which has good performance, long service life, multi-functional integration, small footprint, simple installation, no increase in power, low resistance, and low water consumption. The spray system uses stainless steel 304 material to solve problems such as wear and tear, and effectively solves some practical usage problems of wet desulfurization and dust removal equipment. Boiler dust collectors are currently an ideal environmental protection product for acid mist purification, thermal power plants, cement plants, and other industries in China, including coal-fired, oil fired boilers, coal water slurry boilers, kilns, metallurgy, and chemical industries. The desulfurization and dust removal of boilers using rice husks, sawdust, wood, coal, and other fuels. And dust removal and desulfurization of various kilns.

The boiler bag filter is suitable for dust removal, smoke reduction, and desulfurization of flue gas in coal-fired, oil fired boilers, and kilns. It has the characteristics of low resistance, flexible installation and layout, desulfurization, and long service life.

Working principle of boiler bag filter:

Under the action of the induced draft fan, the dust containing flue gas enters the inlet main pipe (wedge-shaped or stepped air duct) of the dust collector through the flue system from the outlet of the boiler preheater. Then, it is evenly distributed by the guide device in the inlet main pipe and enters the ash hopper of each room through the inlet regulating valve. Coarse dust particles settle to the bottom of the ash hopper, and fine dust particles enter the filter chamber with the airflow turning upwards. The dust is blocked on the surface of the filter bag, and the purified gas enters the clean room through the filter bag opening (flower plate hole). It is discharged from the outlet through the exhaust valve to the outlet main pipe, and then discharged into the atmosphere through the induced draft fan.

The boiler bag filter adopts the technology of chamber stop pulse jet dust cleaning, which overcomes the shortcomings of conventional pulse dust collectors and chamber backflow dust collectors. The dust cleaning, dust removal, low emission concentration, low air leakage rate, low energy consumption, low steel consumption, small footprint, stable operation, and good economic benefits.

Suitable for the purification of dusty gases and material recovery in industries such as metallurgy, building materials, cement, machinery, chemical engineering, power, and light industry. Due to the use of chamber stop pulse jet cleaning, which can achieve the purpose of cleaning with only one injection, the cleaning cycle is extended, reducing the energy consumption of cleaning and greatly reducing the consumption of compressed air. At the same time, the fatigue level of the filter bag and pulse valve is correspondingly reduced, thereby doubling the service life of the filter bag and valve plate. Maintenance and bag replacement can be carried out in separate rooms without stopping the system fan and under normal operating conditions of the system. The opening of the filter bag adopts an elastic expansion ring, which has good sealing performance and is firm. The filter bag keel adopts a polygonal shape, reducing the friction between the bag and the keel, extending the life of the bag, and making it easy to unload the bag. Adopting the upper bag extraction method, the framework is removed during bag replacement, and the dirty bag is put into the lower ash hopper of the box, which is taken out from the manhole to meet the operating conditions for bag replacement. The box adopts an airtight design with good sealing performance. The inspection door uses excellent sealing materials, and the air leakage rate is very low. The layout of the inlet and outlet channels is compact, with low airflow resistance. The dust collector is equipped with insulation devices to prevent condensation of flue gas due to low temperature.

Key installation points for boiler bag filter:

1. Gravity settling effect - When dusty gas enters the bag filter, large and heavy dust particles settle under the action of gravity, which is the same as the effect of the settling chamber.

2. Screening effect - When the particle diameter of dust is larger than the gap between the fibers of the filter material or the gap between the dust on the filter material, the dust is blocked when the airflow passes through, which is called screening effect. When the accumulation of dust on the filter material increases, this effect becomes more significant.

3. Inertial force action - When the airflow passes through the filter material, it can wrap around the fibers, while larger dust particles still move in their original direction under the action of inertial force, and thus collide with the filter material and are captured.

4. Thermal motion effect - lightweight and small dust (less than 1 micron) that moves with the airflow, very close to the airflow streamline, and can bypass fibers. But after being collided by gas molecules undergoing thermal motion (i.e. Brownian motion), they change their original direction of motion, which increases the opportunity for dust to come into contact with fibers, allowing dust to be captured. When the fiber diameter of the filter material is finer, the porosity is smaller, and its capture rate is higher, so it is more conducive to dust removal.

Technical parameters of boiler bag filter:

1. Installation boiler capacity: 8-120T

2. Dust collector inlet flue gas volume: 20000-360000 m3/h

3. Dust concentration in dust collector flue gas: 25-30g/m3

4. Dust collector outlet emission concentration:<50mg/m3

5. Normal temperature range for flue gas operation: 140~190 ℃

6. Filter area of dust collector: 300-6000m2

7. Filtering wind speed: 0. 7-1. 0m/min

8. The dust collector uses filter material: PPS filter material

9. Total resistance of dust collector operation: 1200-1500Pa

10. Dust collector body air leakage rate:<3%

11. Design pressure of dust collector housing: static+5000Pa, -6500Pa.