Causes of paste bags(2)

Adhesive paste bag

Mainly because the dust adhesion is relatively large, although no condensation occurs, the dust still adheres to the surface of the fiber, and the online cleaning system cannot remove it. The reasons for the adhesive paste bag may come from the following situations.

① The dust itself has a relatively high viscosity, and when it comes into touching with the filter fiber, the intermolecular force is relatively strong. For example, oily particles, ammonium sulfate formed by denitration, and limestone used for desulfurization.

② Although some dust is not sticky, it is easily deliquescent. When it is trapped on the surface of the fiber, it absorbs moisture from the air and forms a solution on the surface of the fiber. For example, powdered sugar.

③ Some dust adhesion may not be strong, but it can absorb the moisture in the flue gas and carry out the chemical process of recrystallization to generate new hydraulic substances or crystals, and the formed “crust” covers the surface of the filter. For example: cement clinker, the product of desulfurization —— calcium sulfate.

④ Even if the dust itself is not sticky, if the dust particles are fine and the water content of the dust is relatively large, the dust is easily adsorbed evenly on the surface of the filter material to form a layer of “floating ash”, and the adhesion is not very strong, but very hard to remove. The longer the running time, the thicker the “floating ash”. This may happen in general coal-fired power plants, especially for filter bags longer than 6 meters. For some reason, a northern power plant has caused the running resistance of the precipitator to rise to 2200Pa in a short period of time from around 1500Pa, causing serious downtime of the entire line.

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