Boiler bag filter

The boiler bag filter adopts a two-stage combined dust collector unit. This unit consists of a flame arrester and a bag filter system. It selects PPS filter material with better performance to make the bags. A flame arrester is installed in front of the bags. The system uses split flow and wave-following air intake technology. It has the advantages of reliable operation, high dust removal efficiency, simple operation, and emission compliance.

Essentially, boilers generate steam for processing plants, power plants, and various other industries. Boilers can use natural gas, electricity, oil, solid fuels, liquefied petroleum gas, or renewable energy sources as fuel to produce steam. Among all fuels, solid fuels are the cheapest, the most polluting, and the most widely used.

To control emissions from wood/coal/brown coal boilers, bag filters must be used. The pollution control system for these boilers will limit the levels of suspended particulate matter emissions, and if sulfur gas is also a limiting factor, a venturi-type wet scrubber should be used in conjunction with the boiler bag filter.

Darko manufacture high-quality boiler bag filters and supply them globally. Due to our customer-centric approach, we are one of the most popular suppliers. As a reliable manufacturer, we provide high-quality bag filters for boilers.

Working principle of  Darko boiler bag filter

The dusty gas enters the ash hopper of each unit through the guide pipe. The ash hopper guide system separates large dust particles, which fall directly into the ash hopper.The remaining dust flows into the filter area of the middle box with the airflow. The clean gas, after passing through the filter bag, is discharged through the upper box, lift valve, and exhaust pipe. As filtration proceeds, the dust accumulates on the surface of the filter bag. The dust cleaning control device then closes the lift valve according to the set program. It opens the electromagnetic pulse valve to spray, shaking off the dust from the filter bag. The dust falls into the ash hopper and is discharged through the ash discharge valve.

Darko boiler bag filte applicable fields

• Dust control in cement plants, and widely used in the field of deep processing of non-metallic mineral powders, and also has good application prospects in the power, chemical, metallurgy, steel and other industries.

• Coal-fired boilers and heavy oil-fired boilers for industrial and heating.

• Dry and wet cement rotary kilns, vertical kilns, raw and clinker mills.

• Copper, lead, zinc sintering, copper smelting furnaces, electric arc furnaces, reverberatory furnaces.

• Iron ore sintering machines (head and tail), blast furnaces, open hearth furnaces, coke ovens, converters, electric arc furnaces and refractory industries.

Darko boiler bag filter system composition  

The boiler bag filter consists of the bag filter body, protection system, compressed air system (including air storage tank, oil-water separator, pipeline), control system (including instruments, PLC cabinet, MCC cabinet, on-site operation cabinet), etc.

(1) Box body:

It consists of upper box body (clean air chamber), middle box body (filter chamber), lower box body (ash hopper), flue gas distributor, flower plate, platform, escalator, support feet, air inlet, ash outlet, insulation, color panel, etc.

(2) Filter bag composition:

The connection design of the filter bag frame, cloth bag and hanging bag adopts a self-locking device, which is convenient for installation and replacement, and can effectively extend the service life of the filter bag. The filter bag specifications are: ￠130×2450 mm, ￠130×6000 mm, ￠160×6000 mm, using polyphenylene sulfide needle felt (imported PPS/PPS 504CS17, waterproof and oil-proof treatment).

(3) Heat diversion device:

It adopts the upward air intake method and is designed as a flue gas distribution device. It can not only effectively distribute dust-containing gas, but also separate large particles to avoid dust-containing gas from scouring the filter bag. Further improve the dust removal efficiency. Improve the service life of the filter bag.

(4) Pulse jet system:

It composes of recoil air box, electromagnetic pulse valve, pressure joint, nozzle pipe, bracket, etc. The specifications below GDM-5.6 are for whole box cleaning, and the other specifications have a compressed air nozzle pipe on the top of each filter bag. During operation, the system typically performs pulse backwash cleaning every 10 seconds for each row of filter bags. The system activates the electromagnetic valve at a fixed time. Then it sprays pulse backwash compressed air into the filter bag for cleaning.

(5) The ash discharge system:

It consists of an electric vibrator (air cannon), an electric heater, and an ash level indicator. The electric vibrator (air cannon) ensures that the dust has good fluidity.

(6) The control system:

The system comprises several components. It includes a pulse jet controller and an MC computer control cabinet. It also features a thermal resistance thermometer, a static pressure measuring point, and a material level indicator. Additionally, it contains a measuring element.

(7) Offline protection system:

There are sveral main components of the boiler filtration. These include a bypass valve, an emergency water spray system, and a differential pressure device. It also features a material level meter, a thermometer, and a pressure detection device. Additionally, the system includes a pulse controller and a filter bag leak detection device.

Technical features

① High temperature resistant filter material application technology:

The boiler bag filter system combines the characteristics of my country's coal-fired boiler flue gas. It uses cost-effective, high-temperature, and corrosion-resistant boiler filter material. The fiber is treated with a PTFE membrane. This approach resolves the issue of high flue gas temperatures that ordinary filter materials cannot withstand. It also addresses the short service life of ordinary filter materials. Additionally, it considers the performance-price ratio of the filter material.

② Offline maintenance technology:

The application of new lifting valve technology enables the non-stop maintenance function of the bag filter. Users can select between offline and online cleaning methods at will. The protection device of the lifting valve eliminates failures caused by lifting valve issues. This ensures that the bag filter will not affect the operation of the boiler.

③Bag filter protection technology:

The use of online detection equipment addresses specific protection issues for the bag filter. This equipment includes an external bypass system and temperature and humidity measurement tools. It solves the protection problem when the boiler adds oil to assist combustion and during boiler failures.

④Detection and monitoring technology:

According to the use characteristics of the boiler bag filter, We establish online detection and monitoring . This includes flue gas temperature, humidity, dust collector operation pressure detection, material level detection, and operation equipment failure detection. These systems can complete all measurement, monitoring, control, alarm, protection, and interlocking functions in the bag filter. They also allow for real-time monitoring of the dust collector's operation.

⑤PLC programmable controller technology:

The PLC programmable controller is provided by SIEMENS. It has a communication interface with the system DCS. This setup allows for manual and automatic control of the bag filter.

⑥Equipment resistance control:

Darko guarantee the safety and reliability of the overall resistance of the bag filter. We achieve this through a series of unique considerations in equipment design. This assurance comes from two aspects: the equipment structure and the filter material.

The application of these advanced technologies ensures that the bag filters produced by our company feature mature technology. Additionally, they offer an excellent price-performance ratio.