Introduction to the advantages and disadvantages of dust bags

Dust filter bag is the entire dust removal system plays an extremely important role, but dust filter bag as a loss of goods also has different degrees of advantages and disadvantages, such as although you can achieve more than 99.99% of the dust removal efficiency, but may face accelerated consumption of dust filter bag due to the working conditions, then the dust filter bag and what are the advantages and disadvantages？

Advantages of dust filter bags:

1. High dust removal efficiency, generally up to 99.99% and above. Low dust discharge concentration, generally lower than 50mg/m3, even up to 10mg/m3 below.

2. Strong adaptability to dust, can capture high specific resistance dust and dust with high SiOZ + AID3 content, low sulphur, high ash coal dust, not sensitive to the physical and chemical properties of dust.

3. The inlet dust concentration varies considerably, which has less influence on the dust removal efficiency and resistance.

4. Simpler structure, smaller land area, lower primary investment, can be done online in separate chambers to rotate maintenance and bag replacement. With dry and semi-dry desulphurisation system, it has certain desulphurisation effect.

5. The service life of the dust bag can reach 30,000 hours.

Disadvantages of dust filter bag:

The filter media of the dust filter bag is sensitive to the nature of the soot, such as temperature, humidity, acid dew point, oxygen content, etc. Although there is already a temperature-resistant 170-190 ℃ dust bag, but must be equipped with temperature reduction measures. The following network to PPs dust bag as an example of the relationship between flue gas oxygen content, flue gas temperature, service life. It shows that in the case of ensuring the service life of the dust filter bag, the higher the oxygen content of the flue gas, the lower the temperature of the dust filter bag used, because every 10'C increase, the chemical reaction into a double increase. That is to say, the original life of 4 years, if the temperature increases by 100C, its life will only be 2 years due to the higher cost of the dust filter bag, so the operation and maintenance costs are higher. Equipment system pressure loss is large, generally at 1500-2000 Pa. Improper combustion control in boiler operation directly affects the service life of the dust collector dust filter bag.

At the beginning of the use of the dust filter bag, the dust removal mechanism that plays a major role is inertial collision, diffusion and retention, in addition, electrostatic force and gravity also play a role. The efficiency of dust removal during this period is slightly lower than during normal use. However, the dust layer (often called the filter cake layer) that accompanies the dust deep into the surface of the filter media, the baghouse is in normal use inside the filter media, so that the fibre space is gradually reduced and eventually formed to attach to the period mainly relying on this initial layer and the dust layer that gradually builds up afterwards to act as a dust remover. It is usually dependent on the fibre density of the filter media in the thickness direction to determine the filtration capacity. That is, the surface area of all the fibres of the filter media (the influence of the grammage of the filter media; the influence of the fine denier, the influence of the shaped cross section of the fibres, the influence of the specific gravity of the fibres, etc.).

In the case of ensuring the service life of the dust filter bag, the higher the oxygen content of the flue gas, the lower the temperature at which the dust filter bag is used, because every 10'C increase, the chemical reaction becomes doubly increased. That is to say, the original life of 4 years, if the temperature increases by 100C, its life will only be 2 years due to the higher cost of the dust filter bag, so the operation and maintenance costs are higher. Equipment system pressure loss is large, generally in the 1500-2000Pa. boiler operation inappropriate combustion control, directly affect the dust collector dust bag service life.