Boiler bag filter

The boiler bag filter is composed of the XLDM offline dust cleaning low-pressure pulse bag filter body, protection system, compressed air system (including storage tank, oil-water separator, pipeline), control system (including instruments and meters, PLC cabinet, MCC cabinet, on-site operation cabinet), etc., which runs smoothly, has low resistance, low energy consumption, good dust cleaning effect, and occupies a small area. Working principle of boiler bag filter:

Coal smoke dust enters the filtering chamber of each unit from the incoming material, and is drained through the smoke distribution device to enter the filtering chamber in all aspects; The dust in the flue gas settles directly into the dust collector through physical force in the air inlet channel. The fine dust airflow is guided and attached to the outside of the dust removal bag, while the clean gas is discharged through the dust removal bag, upper box, and exhaust pipe. When the dusty gas enters the boiler bag filter from the inlet, it first hits the inclined partition in the middle of the inlet and outlet, and the airflow turns to flow into the ash hopper. At the same time, the airflow speed slows down. Due to inertia, the coarse particles of dust in the gas directly fall into the ash hopper, playing a role in pre dust collection. The airflow entering the ash hopper then bends upwards and passes through the filter bag with a metal frame inside. The dust is captured on the outer surface of the filter bag, and the purified gas enters the clean room at the upper part of the filter bag chamber, where it is collected and discharged through the air outlet pipe.

As the filtration time prolongs, the dust trapped on the filter bag gradually thickens, and the resistance of the filter bag increases. At this time, each dust collection chamber is cleaned alternately according to the given time interval. Each dust collection chamber is equipped with a lift valve. When cleaning the dust, the lift valve is closed to cut off the filtered airflow passing through the dust collection chamber. Then, the pulse valve is opened to spray high-pressure air into the filter bag to remove the dust on the outer surface of the filter bag. The pulse width and cleaning cycle of each dust collection chamber are programmable controlled by PLC.

Boiler bag filter products can be widely used in dust collection systems such as crushing, packaging, warehouse roofs, clinker coolers, and various mills in cement plants. If used for coal mill dust collection, performance stability measures should be added, and the structure of the dust collector should also be changed accordingly. It is also suitable for dust collection of gases with extremely high dust concentration, such as the grinding system with O-Sepa powder selector. The gas dust concentration can reach over 1000g/m3. When using this series of dust collectors for dust collection, cyclone dust collectors can be omitted as the main product for dust collection. In addition to being used in the cement industry, it is also suitable for dust collection of exhaust gases from metallurgy, chemical industry, machinery, and civil boilers. The material of this series of dust collector filter bags is generally polyester needle punched felt, which allows continuous use at temperatures below 120 ℃. If the filter bag is made of aramid needle punched felt, its allowable operating temperature can reach 210 ℃, but the filter material made of this material is expensive. If the temperature of the treated exhaust gas is higher than the allowable temperature of the filter material mentioned above, cooling measures should be taken before the exhaust gas enters the dust collector.

The boiler bag filter adopts an external filtration method, and the filter bag of the dust collector is connected to the flower plate self-locking by a spring expansion ring, separating clean air from dusty gas. The filter bag is supported by a bag cage.

The boiler bag filter sends a pulse signal from the PLC to the electromagnetic pulse valve during dust cleaning, and sprays compressed air through the blowing pipe to radially deform the filter bag and shake off the dust. The boiler bag filter dust removal system is equipped with a bypass pipeline, which allows the flue gas to be discharged through the bypass pipeline without passing through the filter bag in the event of boiler oil injection, abnormal smoke temperature, or "four pipe" bursting, thus effectively protecting the dust collector.

The boiler bag filter is equipped with an online detection device for flue gas temperature. When the flue gas temperature is too high or too low, exceeding the preset alarm value, the bypass system valve is automatically opened to discharge the flue gas and protect the filter bag. The dust collector inlet airflow distribution device ensures that the dust containing gas entering the dust collector is evenly distributed in each filter bag, effectively preventing collisions and friction between the filter bags during the dust cleaning process, which is beneficial for extending the service life of the filter bags. The dust collector ash hopper is equipped with an electric heating device to prevent ash accumulation and plate formation; The vibration cleaning device promptly removes the accumulated dust in the dust collector, ensuring the smooth unloading of dust from the dust hopper of the dust collector. The entire boiler bag filter control system adopts PLC for automatic control. The control circuit has sufficient interfaces to connect to DCS for monitoring. Dust collector electrical control cabinet is dust-proof, stable in performance, and resistant to small animals.