Pulse bag filter is a bag filter designed and manufactured by absorbing technology from FULL company, which can directly process high dust concentration gases. The air box pulse bag filter uses BWF filter material filter bag ASCO pulse valve and SIMENS PLC. Complete machine configuration and dust removal. The pneumatic pulse bag filter has a type similar to coal mills.
Pulse bag filter is a horizontal bag filter equipment that combines the advantages of chamber back blowing and jet pulse bag filter. It overcomes the shortcomings of insufficient kinetic energy for cleaning in chamber back blowing and simultaneous cleaning and filtering in jet pulse, and expands the application range of bag filter equipment. It combines the essence of similar products with our company's environmental protection technology to improve the dust removal efficiency and operability of the pneumatic pulse bag filter, extend the service life of the filter bag, reduce the labor intensity of operators, and become a good partner for enterprises to protect the environment.
The pulse bag filter has a bag filter of 21st century level. It combines the advantages of various types of bag dust collectors, such as chamber back blowing and jet pulse dust cleaning, overcoming the disadvantages of insufficient chamber back blowing dust cleaning intensity and simultaneous jet pulse dust cleaning and filtration. Therefore, it expands the application range of bag dust collectors. Due to the unique structure of this type of dust collector, it improves dust collection efficiency and extends the service life of filter bags.
When the dusty gas enters the dust collector from the air inlet, it first hits the inclined partition in the middle of the air inlet, and the airflow turns to flow into the ash hopper. At the same time, the airflow speed slows down. Due to the gravity settling effect, 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.
The air inlet of a bag filter may seem simple, but there is actually a lot of knowledge involved. A good bag filter needs to design a reasonable air inlet. Whether the air inlet of a bag filter is reasonable directly affects the dust cleaning system of the dust collector. When designing the air inlet of a dust collector, we consider uniform air distribution, and secondly, we consider which air inlet method to use based on the site conditions of the dust removal system.
The downward air intake method refers to the entry of dusty airflow from the lower part of the box or the ash hopper. Due to the sudden diffusion of the airflow, the flow rate suddenly decreases, and some larger particles of dust fall into the ash hopper under the action of gravity. Afterwards, the airflow is distributed through the guide plate and guided to the filter element, while some larger particles of dust directly settle, thus reducing the wear on the filter bag, reducing the deposition of dust particles on the dust removal bag, and extending the time interval for dust cleaning; But when using the reverse blowing method for dust cleaning, the settling direction of the particles being cleaned is opposite to the direction of the dust cleaning airflow, which not only hinders the settling of smoke and dust, but also generates "secondary dust" during reverse blowing, affecting the effectiveness of dust cleaning, especially when using long cloth bags, this phenomenon is obvious. Of course, the downward air intake method has a relatively simple structure and low cost, making it a commonly used method.
The side air intake method is generally used in external filter bag filters. Eropals Company has studied the full lateral intake method, which also has significant advantages. Figure 2 shows the fully lateral intake method used. When using this method, the dusty gas enters the flue from the side of the box, and then passes through the flue gas distribution device to evenly distribute the dusty gas. This can achieve coarse separation of large-diameter solid particles, thus avoiding direct flushing of the filter bag, protecting the filter bag, and improving the efficiency and performance of the entire dust removal system; Moreover, due to the lateral intake, the upward velocity of the generated airflow is relatively low. When dust falls from the top of the dust collector into the ash hopper, the possibility of it being carried away again is relatively reduced. The experience of a certain company also proves that under the same filtering wind speed, the same dusty gas flow rate, and achieving the same dust removal efficiency, the resistance loss of the inlet air is smaller under the full lateral air ratio, which can reduce operating costs, reduce system energy consumption, and save costs.
The dusty flue gas enters from above the filter bag and is discharged from below, which is called the upper inlet air method. In the upper inlet bag filter, the settling direction of dust in the dusty flue gas is the same as the movement direction of the flue gas. Therefore, during the downward flow process, regardless of the particle size of the dust particles, there is a chance that they will not be captured by the filter bag and fall into the ash hopper. The upper air bag filter has better performance in handling aerosols with high dust content, and the resistance of the equipment is relatively low. However, dust collectors generally require multiple flower plates, complex mechanisms, and difficulty in adjusting the tension of the filter bag. There is stagnant air in the ash hopper, which is prone to dust accumulation and the possibility of condensation of water vapor. In addition, dust cleaning is inconvenient, so this method has gradually been phased out and is now basically not used.
With the development of bag dust removal technology and the increasing demand for environmental protection, the application scope of bag dust collectors is becoming more and more extensive. Currently, bag dust collectors can be used to treat high temperature, high humidity, adhesive, explosive, abrasive flue gas, and even filter air containing dust.
1. Adhesive dust is prone to agglomeration on the surface of filter bags. Bag filters can treat adhesive dust through adsorption, which involves adding an appropriate amount of porous powder into the system pipeline, using the powder to adsorb the adhesive dust, and then purifying it with the bag filter. If the refractory plant uses dolomite powder to adsorb and purify asphalt smoke, the aluminum plant uses alumina to adsorb asphalt and hydrogen oxide, and the asphalt concrete workshop of the road company uses limestone powder to adsorb asphalt smoke, the adsorption efficiency can reach 92~.
2. The flue gas from various industrial kilns, dryers, etc. is classified as high-temperature flue gas, which mostly contains a large amount of moisture and sulfur oxide gas. Bag filters are currently capable of processing flue gas with temperatures below 300 ℃. If the temperature exceeds this range, the flue gas should be pre cooled. In this case, metal fiber filter media can be used to directly process high-temperature flue gas at 450-550 ℃. The use of bag filters to treat flue gas from high-temperature kilns such as steam boilers, cement kilns, metallurgical furnaces, and incinerators is becoming increasingly common. Although bag filter is limited by the temperature resistance of its filter material, it can handle high-temperature flue gas with temperatures up to 1200-1400 ℃ by appropriate treatment of the system flue gas.
3. Explosive dust will only explode when it meets the following three conditions simultaneously:
Combustible substances exist in flue gas at appropriate concentrations;
Having sufficient oxygen and oxidants;
There is a source of ignition. Therefore, when purifying such gases, measures should be taken to disrupt the above three conditions or one of them. Simply put, it means controlling the composition and eliminating the spark; Static electricity and equipment grounding; Monitoring, extinguishing and explosion.
4. When dealing with abrasive dust such as alumina, silica, and sintered ore, the coarse particles in the smoke and the high speed of the airflow in the bag filter cause strong wear on the filter bag and shell of the dust collector. Therefore, corresponding measures should generally be taken from two aspects: reducing the amount of coarse particle dust in the flue gas and reducing the flow rate of the dusty gas. For example, a pre dust removal device should be installed before the flue gas enters the bag filter, the inlet flow rate of the filter bag should be strictly controlled, and materials should be added to the easily worn parts of the airflow inlet.
