Bag filter dust collectors are relatively insensitive to the properties of smoke and dust generated by coal-fired power plants. Generally speaking, coal quality does not have a significant impact on the operation of bag filters. But there are exceptions, and caution should be exercised when selecting bag filters based on the results of demonstration projects.
The design of the filter bag will interact with the smoke and dust to be collected, and the same filter material can have a significant impact on pressure drop and dust concentration in power plants due to slight differences in design.
The operation process design of bag filter can also have a serious impact on the operating effect of bag filter. Frequent dust cleaning often leads to high smoke and dust emission concentration, and significantly shortens the service life of filter bags. Therefore, it is necessary to optimize between dust cleaning frequency and pressure drop.
Bag filters used in power plants are usually divided into multiple unit rooms, allowing the filter bags to be closed, repaired, or replaced online. The filter bag is prone to damage when facing high-speed airflow, which often occurs on newly installed filter bags. Therefore, careful control should be exercised during the start-up of newly installed (replaced) filter bags.
The resistance of the filter bag after cleaning comes from two aspects: the particles in the filter bag fibers and the ash layer attached to the bag that has not been removed during the cleaning process. The cleaning effect is related to the cleaning energy entering the bag and the strength of the ash layer attached to the bag. Some deviations during operation may lead to an increase in the strength of the ash layer. For example, low-temperature operation can cause acid condensation on the ash layer, boiler pipeline leaks can cause smoke and dust to carry water and harden the ash layer, and improper fuel operation can cause smoke and dust to carry oil.
