The bag filter belongs to the mechanical dithering dust collector, which collects and separates dust particles from the airflow. It adopts the mechanical vibration dust removal equipment. The machine can be equipped with shot blasting machine, sand blasting machine, crusher, sand screening machine, sand mixer and other equipment with high dust concentration. Practice has proved that the bag filter runs steadily, has low noise, high dust removal efficiency and is convenient for operation and maintenance.
The blower of bag filter adopts centrifugal blower, which has large air volume and high air pressure, and adopts silencing measures with low noise. The filter adopts flat cloth bag group, each bag is equipped with spring wire mesh, and the filtering effect is good. The dust cleaning mechanism uses the motor to drive the eccentric wheel and connecting rod to make the bag shake and dust on the surface of the filter bag. The bag filter has an overhaul door to facilitate overhaul and bag replacement. Mainly by the shell, high-pressure fan, filter bag, dust collection drawer, abdominal cavity, air intake pipe, air duct, circuit devices and other components. It is mainly suitable for dust removal and cleaning in foundry industry, ceramics industry, glass industry, refractory materials, cement building materials, grinding wheel manufacturing, chemical reagent processing, mechanical processing, mining metallurgy, machine tools, grinders and other industries. Its dust removal efficiency is over 99.5%.
The bag filter is a dry filter. It is suitable for trapping fine, dry and non-fibrous dust. The installation and operation quality of bag filter play an important role in the normal operation of production line. Therefore, attention should be paid to the installation, construction, operation and maintenance of bag filter in order to ensure the stable and good operation of bag filter and ensure the smooth operation of production. Bag filter is mainly used in cement mill, kiln tail and other systems, and plays an important role in production. Some bag filter dust removal systems can not start up in operation, mainly manifested in the following aspects: fan rotation does not smoke, electric furnace hood suction is insufficient, smoke escapes, three chimneys still smoke; hood, cooler, dust collector bag and induced draft fan are not matched, the system capacity is generally inadequate; hood, cooler, bag filter and induced draft fan have structure. It is unreasonable and has insufficient capacity; it is not standardized to produce dust; it is disorderly to dispose of smoke and dust, and the second dust can be seen everywhere; there is no scientific management system to ensure orderly operation.
Bag filter has many advantages, such as high dust removal efficiency, convenient operation and maintenance, and can meet the discharge standards. It is accepted by more and more dust control systems. But bag filter is not available anywhere. It needs special attention when used in the following working conditions.
1. Where the temperature is particularly high
If the temperature exceeds 350 C, the bag filter can not be used directly, because the temperature is too high for the bag to bear, it will be burned, even if using the high temperature dust bag, it can not withstand the high temperature of 350 C. Cooling measures should be taken before high temperature dust enters the bag filter.
2. Where the humidity is too high
It is not suitable to collect smoke with too much oil, and the humidity is too high. Too much oil in the flue gas often causes the filter bag to bind and clog the filter material; if it is a little humid, the filter bag in the bag filter can choose water-repellent and oil-proof filter bag, or the bag filter can take thermal insulation measures to ensure that the moisture in the gas will not condensate.
Start-up conditions of bag filter
1. Start the air compressor fan, the fan works normally, and adjust the pressure of the separator chamber of the dust collector from 0.2 to 0.4 MPa.
2. Dust collector flue gas inlet temperature 120-180 C
3. The dust collector can receive flue gas only after the boiler has withdrawn oil and put coal into stable combustion.
4. Make sure that the bypass door of the dust collector is closed tightly and the baffle door of the entrance and exit of each dust collector is flexible.
5. Compressed air pressure meets the requirements, put into the ash removal system one hour ahead of schedule, and start the small dust collector on the ash depot.
6. Put into the ash hopper heating device 8 hours before starting the dust collector.
7. The pressure and quality of compressed air to ash cleaning system are qualified.
8. Compressed air pipeline and oil discharge and drainage valves of gas storage tanks are opened. There is no oil accumulation and water accumulation in oil discharge of pipelines and gas storage tanks.
The following points should also be paid attention to in processing and manufacturing.
1. The connection between the filter bag and the flooring board should consider not only the convenience of disassembly and assembly when changing the bag, but also the tightness of air leakage, preventing short circuit of air flow and reducing dust removal efficiency.
2. When external filtration is used, the cage bone surface supporting the filter bag is smooth and smooth, and sharp bulges or corner burrs are not allowed to prevent puncture or excessive wear and tear of the filter bag, resulting in short-circuit air flow and reducing dust removal efficiency.
3. When internal filtration is adopted, the upper suspension mechanism and the lower flooring board should be centered to ensure that the filter bag has enough verticality and equal strip spacing; the lifting tightness of the filter bag should be kept consistent to prevent the filter bag from transitional deformation and affect the normal operation of the dust collector.
4. Pulse valves, solenoid valves and pulse control instruments for pulse ash cleaning are required to have good performance, flexible operation and long-term continuous operation.
5. The reversing valve and its control device with air back suction or air back blowing for ash removal are in place, flexible in action, light in operation and tight in closing.