The corrosion of the dust bag is often caused by three gases. We have summarized that the following three gases will cause corrosion of the dust bag.
1. Strong oxidants: For example, when the PPS dust bag is operated at 160°C and encounters an oxygen content exceeding the standard (>12%), a large amount of oxygen can attack the S bonds in the PPS molecule and combine with it. As a result of the reaction, the PPS fiber becomes dark and brittle and its strength decreases. Sometimes you will find that the surface of the PPS fiber bag exposed to the sun will turn brown. If it is not handled for a long period of time, it will easily cause a drop in fiber strength, resulting in breakage of the dust bag due to a strong drop. The air contains 21% oxygen and 79% nitrogen (volume ratio). When the temperature is not high, nitrogen is stable, but the high temperature will break the nitrogen molecular chain and react with oxygen to form NO and NO2. NO can not be considered, but NO2 is a strong oxidant and can oxidize most of the fibers used for filtration. . Oxidizers include nitrogen oxides, hydrogen sulfide, ammonia, and chlorine. Enhanced control over process and equipment can reduce oxidative corrosion.
2. Acid gases: Mostly appear in the use of high-temperature filter materials, mainly sulfide. If there is more acid gas in the high-temperature flue gas, it is recommended to use a dustproof bag with better acid resistance. If an ordinary dust bag is used, acid flue gas may corrode the fiber structure inside the dust bag, resulting in a strong drop of the dust bag and eventually damage. Damage marks from outside to inside. Reducing the temperature can reduce the acid gas’s corrosion on the dust bag. Acid gases include sulfur dioxide, sulfur trioxide, hydrogen sulfide, hydrogen chloride, and hydrogen fluoride.
3. Alkaline gases: Mostly appear in conditions containing ammonia, mainly ammonia. The type of damage and acid corrosion is that reducing the temperature can reduce the corrosion of the dust bag by the alkaline gas.