Reasons for dew condensation in the boiler filter bags

1. There is air leakage in the boiler filter bags, Due to the phenomenon of air leakage in the dust collector, a large amount of cold air from the outside is sucked into the dust collector, so that the local air temperature of the bag filter drops sharply, and the water in the air is analyzed, resulting in a dust collector bag. condensation phenomenon. There are many reasons for the air leakage of the bag filter, including the leakage of the dust collector shell during the production and installation process, which causes air leakage, the unsealing of the unloading device, which causes air leakage, and the leakage of non-standard pipes during the installation process. Air leakage, air leakage caused by poor sealing of the connection between the dust collector and the non-standard pipe flange, etc.

2. The moisture content in the flue gas is too high. When the moisture content in the treated flue gas is too high, the supersaturated water is analyzed, which will cause condensation in the dust collector bag.

3. The flue gas temperature is too low When the temperature of the flue gas treated by the dust collector is close to or lower than the dew point temperature, condensation will also occur.

4. The temperature of the pulse jet gas is too low The bag filter uses compressed air in the pulse jet cleaning process, and the compressed air itself is saturated air with a relative humidity of 100%. Since its air pressure is greater than atmospheric pressure, the dew point converted to atmospheric pressure is lower than the ambient dew point, and there is a tendency to dew condensation. When the temperature of the compressed air is not much different from the temperature of the flue gas inside the bag filter, dew condensation generally does not occur. However, in winter, especially in northern my country, when the temperature is usually minus ten or tens of degrees, the temperature difference between the compressed air injected by the pulse and the flue gas inside the dust collector is too large. When the compressed air is instantly injected into the filter bag The temperature also drops sharply, usually in the form of a white mist spraying out a high-speed airflow of condensed water mist, and the temperature within a certain distance below the nozzle is relatively low, forming a low temperature area. Since the compressed air in the nozzle is saturated air, the temperature drop after the gas is ejected will cause the water to separate out in the area and cause condensation in the bag of the dust collector. At this time, the condensation is mainly concentrated on the surface of the dust bag being blown, and the dust adhering to the surface of the dust filter bag is bound by absorbing the moisture from the condensation, which in turn blocks the pores of the dust bag, resulting in the dust collector not working normally. .

5. The shell of the boiler filter bag  has no thermal insulation measures or the effect is not good. The shell of the filter is generally made of steel plate, and the thermal conductivity of the steel plate is very large. When the temperature of the outside air and the temperature of the flue gas inside the filter are relatively large When the temperature is different, condensation will occur on the shell of the bag filter. If the shell of the dust collector does not take thermal insulation measures, or although thermal insulation measures are taken, but the effect is not good, the condensation phenomenon of the dust collector cloth bag is inevitable.

The boiler filter bag are widely used in steel, cement, chemical industry, power plants, road construction, metallurgy, food processing and so on.