Generally, coal types in coal-fired thermal power plants are relatively stable, but they cannot avoid the occurrence of changes in coal types or coal quality. The boiler system is a system that changes and adjusts frequently, so the physicochemical properties and soot of the flue gas coming out of the boiler Parameters such as concentration and temperature are not guaranteed to change. This series of changes can cause significantly different changes for different precipitators. The following is a comparison from the main aspects: First, the amount of boiler soot is constant, and the air volume of the sending and drafting fans changes.
For the bag filter: The change of the air volume directly causes the change of the filter wind speed, which causes the change of the resistance of the equipment, and has no effect on the dust removal efficiency. When the air volume is increased, the resistance of the equipment is increased, and the output of the induced draft fan is increased; otherwise, the output of the induced draft fan is reduced.
For electrostatic precipitators: The change in air volume does not have much impact on the equipment, but the dust removal efficiency of electrostatic precipitators varies significantly with the amount of wind. If the air volume increases, the electric field wind speed of the electrostatic precipitator increases, and the dwell time of the dust in the electric field is shortened. Although the electric field wind disturbance enhances the effective driving speed of the charged dust, it is insufficient to compensate the dust caused by the high wind speed in the electric field. The negative effect of shortening the retention time and intensifying the secondary dusting, so the dust removal efficiency is very obvious; on the contrary, the dust removal efficiency has increased, but the increase is not large.
Second, the air preheater and system piping leaks to the bag filter: For the filter material with poor oxygen resistance, it will affect the bag life, such as: RYTON filter material, but the dust removal efficiency is not affected. The system resistance increases due to the increased air volume mixed into the cold air system. For electrostatic precipitators: there is no significant change in equipment resistance, but the increase in system air volume increases the influence of electric field wind speed on dust removal efficiency. Sixth, the change of flue gas physicochemical composition (or burning coal) to the bag filter: the physicochemical composition of the flue gas has no effect on the dust removal efficiency of the bag filter. However, if the flue gas contains components that are corrosive to all filter materials, it will directly affect the service life of the filter media. For the electrostatic precipitator: the physicochemical components of the flue gas directly cause changes in the dust specific resistance, thereby affecting the dust removal efficiency, and the impact is great. The most direct influence is the content of sulfur oxides in the flue gas. Generally, the higher the content of sulfur oxides, the lower the specific resistance of the dust, the easier the dust is to be trapped, and the dust removal efficiency is high; on the contrary, the dust removal efficiency is low. In addition, changes in the chemical composition of the soot (such as silicon, aluminum, potassium, sodium, etc.) will also cause significant changes in dust removal efficiency.
Third, the influence of air distribution. For the bag filter: the dust removal efficiency is not directly related to the air distribution, that is, the air distribution does not affect the dust removal efficiency. However, the local airflow distribution inside the dust collector should be as uniform as possible, and the deviation should not be too large. Otherwise, the local bag may be broken due to uneven local load or jet wear, which affects the normal service life of the dust filter bag. For electrostatic precipitators: Electrostatic precipitators are very sensitive to the distribution of airflow in an electric field. The distribution of airflow directly affects the level of dust removal efficiency. In the performance evaluation of electrostatic precipitators, the root mean square index of airflow distribution is usually one of the important indicators for evaluating the quality of an electrostatic precipitator.
Fourth, the change in temperature. For the bag filter: the temperature of the flue gas is too low, the condensation may cause the "binder bag" and the shell to corrode, the flue gas temperature is too high, and the filter material allows the temperature to easily "burn the bag" and damage the filter bag. However, if the temperature change is within the temperature range of the filter material, the dust removal efficiency will not be affected. The temperature that causes adverse consequences is at extreme temperatures (accident/abnormal conditions), so effective protection against extreme temperature control must be provided for the baghouse.
For electrostatic precipitators: the flue gas temperature is too low, condensation will cause shell corrosion or high voltage creepage, but it is good for dust removal efficiency; flue gas temperature rise, dust ratio resistance is not conducive to dust removal. Therefore, the flue gas temperature directly affects the dust removal efficiency, and the impact is more obvious. Bag dust collector dust bag
For the bag filter: The change of the air volume directly causes the change of the filter wind speed, which causes the change of the resistance of the equipment, and has no effect on the dust removal efficiency. When the air volume is increased, the resistance of the equipment is increased, and the output of the induced draft fan is increased; otherwise, the output of the induced draft fan is reduced.
For electrostatic precipitators: The change in air volume does not have much impact on the equipment, but the dust removal efficiency of electrostatic precipitators varies significantly with the amount of wind. If the air volume increases, the electric field wind speed of the electrostatic precipitator increases, and the dwell time of the dust in the electric field is shortened. Although the electric field wind disturbance enhances the effective driving speed of the charged dust, it is insufficient to compensate the dust caused by the high wind speed in the electric field. The negative effect of shortening the retention time and intensifying the secondary dusting, so the dust removal efficiency is very obvious; on the contrary, the dust removal efficiency has increased, but the increase is not large.
Second, the air preheater and system piping leaks to the bag filter: For the filter material with poor oxygen resistance, it will affect the bag life, such as: RYTON filter material, but the dust removal efficiency is not affected. The system resistance increases due to the increased air volume mixed into the cold air system. For electrostatic precipitators: there is no significant change in equipment resistance, but the increase in system air volume increases the influence of electric field wind speed on dust removal efficiency. Sixth, the change of flue gas physicochemical composition (or burning coal) to the bag filter: the physicochemical composition of the flue gas has no effect on the dust removal efficiency of the bag filter. However, if the flue gas contains components that are corrosive to all filter materials, it will directly affect the service life of the filter media. For the electrostatic precipitator: the physicochemical components of the flue gas directly cause changes in the dust specific resistance, thereby affecting the dust removal efficiency, and the impact is great. The most direct influence is the content of sulfur oxides in the flue gas. Generally, the higher the content of sulfur oxides, the lower the specific resistance of the dust, the easier the dust is to be trapped, and the dust removal efficiency is high; on the contrary, the dust removal efficiency is low. In addition, changes in the chemical composition of the soot (such as silicon, aluminum, potassium, sodium, etc.) will also cause significant changes in dust removal efficiency.
Third, the influence of air distribution. For the bag filter: the dust removal efficiency is not directly related to the air distribution, that is, the air distribution does not affect the dust removal efficiency. However, the local airflow distribution inside the dust collector should be as uniform as possible, and the deviation should not be too large. Otherwise, the local bag may be broken due to uneven local load or jet wear, which affects the normal service life of the dust filter bag. For electrostatic precipitators: Electrostatic precipitators are very sensitive to the distribution of airflow in an electric field. The distribution of airflow directly affects the level of dust removal efficiency. In the performance evaluation of electrostatic precipitators, the root mean square index of airflow distribution is usually one of the important indicators for evaluating the quality of an electrostatic precipitator.
Fourth, the change in temperature. For the bag filter: the temperature of the flue gas is too low, the condensation may cause the "binder bag" and the shell to corrode, the flue gas temperature is too high, and the filter material allows the temperature to easily "burn the bag" and damage the filter bag. However, if the temperature change is within the temperature range of the filter material, the dust removal efficiency will not be affected. The temperature that causes adverse consequences is at extreme temperatures (accident/abnormal conditions), so effective protection against extreme temperature control must be provided for the baghouse.
For electrostatic precipitators: the flue gas temperature is too low, condensation will cause shell corrosion or high voltage creepage, but it is good for dust removal efficiency; flue gas temperature rise, dust ratio resistance is not conducive to dust removal. Therefore, the flue gas temperature directly affects the dust removal efficiency, and the impact is more obvious. Bag dust collector dust bag
Shower Bracket,Plastic Wall Bracket,Plastic Check Valve,Wall Bracket
ASHOWER , https://www.ashower.com