The reason of dust filter bag hydrolysis

Hydrolysis is defined as a chemical reaction in which water molecules intervene in a polymer of a fiber and cause decomposition.

Synthetic fibers produced from polycondensation polymers are not resistant to hydrolysis. Includes: Polyester, polyimide (P84), NOMEX, COMEX.

Three factors -- high temperature, humidity, and chemicals -- must be present to activate hydrolysis. Polyacrylonitrile homomers, PPS fibers and PTFE fibers are not produced from polycondensation polymers and are often selected to replace fibers with hydrolysis problems. Most of the hydrolyzed traces are turbidity of fiber, and the strength of filter bag is seriously decreased, which can be easily torn by hand. The sewing thread breaks after hydrolyzation, which has no strength.

(1) High temperature cautery

The performance of high temperature burning mainly includes severe shrinkage, severe hardening, and even holes on the surface of the filter bag due to high temperature. The main reason is that the temperature of the filter bag is beyond the range of the filter bag, leading to this phenomenon. Specifically for the high temperature particles, high temperature flue gas, high temperature thermal shrinkage of the filter bag caused by the filter material damage.

(2) Dew blocking

The so-called condensation, generally speaking, refers to moist air in a certain pressure and temperature, saturated moisture precipitation phenomenon. The temperature point at which water is precipitated is called the dew point.

The higher the gas pressure, the lower the dew point. The higher the moisture content in the air, the higher the dew point temperature. When the moisture content in the air is certain and the temperature of the humid air is lower than the dew point temperature, moisture will be precipitated in the supersaturated air, that is, condensation will occur; When the air temperature is higher than the dew point, there will be no moisture precipitation, so there will be no condensation. In addition, if the flue gas contains SO2 components, the more SO2 content, the higher the dew point of the flue gas.