The structural composition of the dust collector for Shengjing biomass boiler includes box assembly, filter bag assembly, flow guide device, pulse injection system, ash discharge system, control system, offline protection system, etc.

1. Pulse spraying system: composed of recoil box, electromagnetic pulse valve, pressure joint, nozzle tube, bracket, etc. Specifications below HGDM-5.6 are for whole box cleaning, while other specifications have a compressed air nozzle tube at the top of each filter bag. During operation, it is generally set that each row of filter bags should be pulse blown back to clean the dust every 10 seconds, and the solenoid valve should be started at a regular time to inject pulse blown compressed air into the filter bags for dust cleaning.

2. Ash removal system: composed of an electric vibrator, an electric heater, and an ash level indicator. The dust generated by the electric vibrator has good fluidity.

3. Control system: mainly composed of pulse injection control instrument, PLC computer control cabinet, thermal resistance thermometer, static pressure measuring point, material level indicator and measuring components.

4. Box body: It consists of an upper box body (clean air chamber), a middle box body (filter chamber), a lower box body (ash hopper), a flue gas distributor, a flower board, a platform, an escalator, support legs, an air inlet, an ash outlet, insulation, colored panels, etc.

5. Filter bag assembly: The connection design of the filter bag frame, dust removal bag, and hanging bag adopts a self-locking device, which is easy to install and replace, and can extend the service life of the filter bag. The specifications of the filter bag are: φ 1306000mm, φ 1606000mm, and φ 1607000mm, using polyphenylene sulfide needle punched felt (PPS/PPS504CSl7, treated).

6. Diversion device: Adopting the upper air inlet method, the designed flue gas distribution device can not only distribute dust containing gas, but also separate large particles to avoid dust containing gas from washing the filter bag, further improving dust removal efficiency and extending the service life of the filter bag.

7. Offline protection system: mainly composed of bypass valve, differential pressure device, level gauge, thermometer, pressure detection device, pulse controller, filter bag leak detection device, etc. Spray water when the flue gas temperature is too high or the boiler tail reignites to prevent damage to the filter bag. A filter bag leak detection device composed of differential pressure gauges and other components is installed in the clean air chamber to promptly alert when the filter bag is damaged. Due to the need to spray fuel during ignition and low load of large tonnage boilers, a large amount of oily gas will be generated. This flue gas will directly enter the dust collector, causing the filter bag powder layer to harden, resulting in system resistance and affecting normal operation. The system adds a bypass pipeline to allow the oil containing gas to be discharged through the bypass pipeline at the moment of fuel injection, thereby protecting the filter bag.

Basic configuration of boiler dust collector:

1. Install rainproof and insulation facilities on the top of the dust collector (such as outdoors)

The boiler bag filter is equipped with rain proof, insulation shed, drainage facilities, and maintenance escalator platform (if outdoors); The connection flange between the ash hopper and the ash discharge valve is designed with a protruding part on the upper eave to prevent rainwater from spreading down and damaging the sealing material. The design of various facilities adopts a humanized concept to protect the top device of the dust collector, facilitate personnel maintenance, use, and management.

The top cover of the boiler bag filter adopts a shear punch sealed top cover, which is suitable for manual opening in terms of weight and size. After all holes and doors are made and assembled, a sealing test is conducted to ensure no deformation or leakage.

The ash hopper of the coal-fired boiler dust collector can withstand long-term temperature and humidity changes and consider anti-corrosion performance. The ash hopper is equipped with maintenance doors, and all maintenance doors and manholes are quick opening, which can be opened flexibly and sealed tightly. To avoid smoke short circuiting and carrying ash, the angle between the inclined side wall of the ash hopper and the horizontal direction should not be less than 60 °, and the ash should flow freely with a storage capacity of not less than 12 hours.

Design and install ash poking holes near the outlet of the ash hopper; The design of the ash hopper and ash discharge outlet allows the ash to flow freely and be discharged from the hopper.

Common knowledge of bag selection for biomass boiler dust collector:

The main combustion media for biomass boilers are rice husks, corn stalks, wood, and sawdust. It is inevitable that there will be unburned sparks. Once they enter the bag filter, they will burn the bag and cause losses.

The biomass boiler dust collector process of Shengjing Environmental Protection adopts a bag filter with good dust removal effect, and uses corrosion-resistant and hydrolysis resistant dust collector filter bags, such as Fumes dust collector filter bags, with temperature resistance between 170-280 degrees. The disadvantages of this filter bag are that the filtering wind speed cannot exceed 1.0, it is not resistant to wear and tear, and is afraid of folding. Its advantage is good temperature resistance. Not afraid of high temperature, not afraid of acid and alkali, biomass boiler dust collector. The filter bag mouth adopts a spring expansion ring, which is easy to use and firmly fixed. The bottom of the bag is reinforced with double-layer filter cloth to prevent premature damage. At the same time, in order to reduce the influence of dust adhesion and oxidation on the surface of the filter cloth, the easy to clean filter cloth we have selected will also undergo surface treatment.

Structure of Shanxi Biomass Boiler Dust Collector Structure of Shandong Biomass Boiler Dust Collector