How is the dust collector filter bag corroded

Corrosion is one of the common reasons for the damage of dust  filter bag. The flue gas contains a variety of corrosive substances. In high temperature environment, the corrosion effect is great, and the filter bag is damaged. The main causes of corrosion are hydrolysis, oxidation and acid-base corrosion. Among them, hydrolysis and oxidation caused more damage, but less acid corrosion, alkali corrosion less.

(1) Acid and alkali corrosion

The main cause of corrosion is the acid and base components contained in the flue gas, and the dew point varies with the concentration of these chemical gases. If the vacuum cleaner starts or stops below the dew point, the SO2 in the exhaust gas will meet the water and form H2SO4, which will cause the fiber of the filter bag to harden and deform, lose strength and damage.

Most traces of corrosion damage are radial and form a large area of discoloration on the surface of the filter bag, resulting in the bag becoming hard and brittle and a small number of irregular circular holes. However, different from the irregular circular holes caused by the burning of Mars through the filter bag, they can be distinguished by the naked eye. Figure 8 shows that the HCl content in the flue gas of chlorination section of a magnesium oxide plant in Henan is extremely high. The average service life of PTFE filter bag is less than 3 months, which is riddled with corrosion and cannot be used any longer. Therefore, if the filter bag pulse cleaning is carried out under this condition, the damage of the filter bag will be accelerated.

In addition to acid and base corrosion, the corrosion of the dust bag by organic solvents can not be ignored. For example, some trace substances in the exhaust gas of waste incineration damage the filter bag. At present, it can not be reasonably explained, because the content of these substances is too low to even be detected, but they do exist in the exhaust gas, causing great harm. Bromine vapor (Br2), for example, can be fatal to bag damage, even in small amounts.

Corrosion is one of the common reasons for the damage of dust filter bag. The flue gas contains a variety of corrosive substances. In high temperature environment, the corrosion effect is great, and the filter bag is damaged. The main causes of corrosion are hydrolysis, oxidation and acid-base corrosion. Among them, hydrolysis and oxidation caused more damage, but less acid corrosion, alkali corrosion less.

(1) Acid and alkali corrosion

The main cause of corrosion is the acid and base components contained in the flue gas, and the dew point varies with the concentration of these chemical gases. If the vacuum cleaner starts or stops below the dew point, the SO2 in the exhaust gas will meet the water and form H2SO4, which will cause the fiber of the filter bag to harden and deform, lose strength and damage.

Most traces of corrosion damage are radial and form a large area of discoloration on the surface of the filter bag, resulting in the bag becoming hard and brittle and a small number of irregular circular holes. However, different from the irregular circular holes caused by the burning of Mars through the filter bag, they can be distinguished by the naked eye. Figure 8 shows that the HCl content in the flue gas of chlorination section of a magnesium oxide plant in Henan is extremely high. The average service life of PTFE filter bag is less than 3 months, which is riddled with corrosion and cannot be used any longer. Therefore, if the filter bag pulse cleaning is carried out under this condition, the damage of the filter bag will be accelerated.

In addition to acid and base corrosion, the corrosion of the dust bag by organic solvents can not be ignored. For example, some trace substances in the exhaust gas of waste incineration damage the filter bag. At present, it can not be reasonably explained, because the content of these substances is too low to even be detected, but they do exist in the exhaust gas, causing great harm. Bromine vapor (Br2), for example, can be fatal to bag damage, even in small amounts.