What are the main factors that affect the dust removal performance of the bag filter?

Dust characteristics pairsBag filterThe impact of efficiencyFor example, the particle size of the dust directly affects the dust removal efficiency and emission mass concentration of the dust collector.

The dust removal efficiency of the filter material in different states increases with the increase of particle size. For the above dust particles, the dust removal efficiency can reach above; For smaller dust particles, the dust removal efficiency is the lowest. The reason is that in this particle size range, the inertial collision, entrapment, diffusion effect, and dust capture mechanism are all at low values.

Whether the dust particles are charged or not also affects the baghouse.

Dust removal efficiency. The charge of dust particles is easy to condense the fine dust, and it is easy to adsorb the filter material that is induced to produce the opposite charge, so as to improve the dust removal efficiency of the bag filter.

The effect of media characteristics on the efficiency of the baghouseThe pore diameter on the surface of the filter material and whether the pores are straight have a significant impact on the dust removal efficiency and emission mass concentration. It can be seen from the above-mentioned filter material filtration process that the surface pore size of the woven cloth filter material is large, the hole is straight, and in the filtration process, the filter material must be loaded with dust and the initial layer of dust must be established, so as to improve the dust removal efficiency of the bag filter. After the initial layer of dust is established and the initial layer of dust is destroyed due to excessive ash cleaning, the dust removal efficiency is very low, and the concentration of dust emission scene is large.

For needle felt filter media, because of its small surface pore size and not straight, the filtration process has little impact on the dust removal efficiency, and the overall dust removal efficiency is higher. For the coated filter material, the surface pore size is smaller, only average), and it is not straight-through, and the filtration process has almost no impact on the dust removal efficiency of the bag filter, and the total dust removal efficiency is the highest, and the emission concentration can approach "zero". There are many varieties of filter materials with different characteristics.

It is necessary to be fully familiar with the characteristics of various filter materials, select them correctly in the design, carefully install them according to the requirements of the filter materials, carefully maintain and use them, master the ash cleaning strength, and do not destroy the initial layer of dust. Otherwise, the dust removal efficiency of the bag filter will be greatly affected, and the emission mass concentration will increase.

The effect of cleaning method on the efficiency of the bag filterThere are many ways to clean the ash, and the cleaning intensity is also different. The intensity of mechanical rapping and chamber back-blowing ash cleaning is weak, the nozzle back-blowing air cleaning is medium, and the pulse ash cleaning is the strongest. When cleaning the ash, it is necessary to grasp the strength and time, especially when the pulse is cleaned, the pressure and time of the cleaning should be adjusted to prevent the initial layer of dust from being damaged, so as to reduce the amount of dust escaping when resuming filtration after cleaning.

Otherwise, the emission mass concentration of the bag filter will increase. Effect of filter air velocity on the efficiency of the baghouseAt the initial filtration stage (before the initial layer of dust is established), for woven fabrics, the small filtration wind speed helps to establish the initial layer of dust quickly; If the filtration wind speed is large, the initial layer of dust will be established slowly, and the emission mass concentration will be large. It has little impact on the needle felt filter media and less on the coated filter media.

The relationship between the dust load accumulated on the filter material and the change of dust removal efficiency under different filtration wind speeds. From the point of view of improving the dust removal efficiency of the bag filter, it is better to choose a low filter wind speed.

If the area of the filter material is reduced, but if the wind speed is too large, the dust that has been deposited on the filter material will be blown up again, which will greatly increase the resistance and will also have a certain impact on the dust removal efficiency.

The main factors affecting the dust removal performance of the bag filter are, firstly, the structure of each machine inside the dust collector, followed by the frequent cleaning of the bag filter, and finally the power of the bag filter when it is working cannot reach the power required for normal operation, resulting in low efficiency, so it affects the dust removal performance of the dust collector.

The main reason is that the technology is immature, and there is still a large space for innovative design, and it will bring convenience to people's lives and will have a better market.

Dust particle size and concentration on boiler bag filter.

The impact of efficiency

The formula for the dust collection efficiency of a theoretical boiler bag filter is only applicable to a single particle size, and the electric field strength is assumed when applied.

is uniform. However, in practice, the effect of space charge caused by the dust is also changed as the dust is removed one after another. So along the length of the dust collector, the change in the electric field strength is very large.

The spatial charge of the dust particles obviously greatly affects the electric field strength, especially when the concentration of fine dust particles entering the electrostatic precipitator is very high. Since most of the Shen flow is determined by the migration rate.

Dumplings are carried by low dust particles, so the charge in the space at the inlet of the dust collector can be strong. However, as the dust particles are removed, the effect of a large amount of current being transferred to the space charge of gas ions is reduced.

If the boiler bag filter is used to cool a gas with a dust concentration of about microns, assuming that the dust removal efficiency is 90%, the dust concentration of the gas will vary along the length of the umbrella eliminator, as mentioned above. As the gas advances along the dust preventer, there is less and less dust in it, and the volt-ampere characteristic curve at a given voltage.

will gradually move in the direction of high current.

The factors that affect the efficiency of the bag filter are as follows:

Gas flow rate: If the gas flow rate is too high, the dust-containing gas will pass through the bag, affecting the capture efficiency of the bag.

Bag material: Choosing the right bag material can improve the efficiency of dust removal. Different material bags have different dust collection efficiency and wear resistance.

Dust particle size: The bag filter is suitable for capturing dust particles with a diameter greater than 1 micron. For fine dust particles, more efficient dust collection equipment is required.

Pretreatment facilities: such as humidification devices, pre-cleaners, etc., can improve the condensation and accumulation of dust materials, thereby improving the efficiency of dust removal.

Spray cleaning system: After the bag filter is used for a period of time, the dust collected on the bag will lead to an increase in resistance and affect the dust removal efficiency. The spray cleaning system can clean the bag regularly to maintain its good ventilation performance, thereby improving the efficiency of dust collection.

Operation and maintenance: Reasonable operation and timely maintenance of the bag filter are also the key to improving the efficiency of dust removal. For example, replace damaged bags regularly, inspect and repair air leaks, etc.

To sum up, there are many factors that affect the efficiency of the bag filter, which need to be considered and improved from many aspects.

1. The nature of the dust, the diameter, shape and dispersion of the filtered dust.

2. The performance of the filter bag, the composition and processing method of the raw materials and fibers of the filter bag, the thickness and the void and other parameters.

3. The parameters of operation, including filtration speed, resistance, flue gas humidity, temperature, operation mode, ash cleaning method, ash cleaning frequency, etc.