布袋除尘设备（袋式除尘器、布袋除尘器）的工作机理是含尘烟气通过过滤材料，粉尘被过滤下来，捕集粗粒粉尘主要靠惯性碰撞作用，捕集细粒粉尘主要靠扩散和筛分作用。布袋除尘设备除尘效果的优劣与多种因素有关，但主要取决于滤料。布袋除尘器的滤料就是合成纤维、自然生长纤维或玻璃纤维织成的布或毡。根据需要再把布或毡缝成圆筒或扁平形除尘滤袋。根据烟气性质，选择出适合于应用条件的滤料。
通常，在烟气温度低于120℃，要求滤料具有耐酸性和性能稳定的情况下，常选用涔纶绒布和涔纶针刺毡；在处理高温烟气(<250℃)时，主要选用石墨化玻璃丝布。在某些情况下，还可选用炭素纤维等特殊材料作为滤料。
其工作原理是含dust gas从下部孔板进入圆筒形filter bag内，在通过filter material的孔隙时，powder is captured on the filter surface, and clean air passes through the filter to exit from the outlet. The dust deposited on the filter can be shaken off mechanically and fall into a hopper.
Bags are designed to capture non-stick, non-fibrous industrial dusts and vapors with high efficiency, capturing particles as small as 0.1 microns. However, when used to handle gases containing water vapor, care must be taken to avoid condensation issues. Bag filters have high filtration efficiency but may require more frequent cleaning or replacement of bags due to clogging.
The main advantage of bag filters is their simplicity in design and operation compared with electrostatic precipitators (ESPs), which require higher power consumption for charging and collecting particles. Another advantage of bag filters is that they allow for easy recovery of dry particulate matter for further use or disposal.
However, there are some limitations associated with bag filters: they have lower filtration speeds than ESPs; larger volumes require more space; higher pressure losses during operation result in increased energy costs; and maintenance costs may be higher due to frequent replacement or cleaning requirements.
In summary, while bag filters offer many advantages over other types of air pollution control equipment such as ESPs or wet scrubbers (wet flue gas desulfurization), their performance depends largely upon factors like filter selection based on specific working conditions within industrial environments where these devices are installed – primarily by determining how well different materials will perform under varying temperatures ranging from low (<120°C) up until medium-high levels (>250°C).
