During industrial production, large amounts of dust are generated, not only polluting the environment but also potentially endangering workers' health. Industrial bag filters, as highly efficient dust removal equipment, are widely used in various industrial settings. So, how do they work? What are the different types of filter bags, their core component? Let's find out.
Working Principle of Industrial Bag Filters
Industrial bag filters operate primarily based on the principle of filtration and separation. After dust-laden air enters the dust collector through the air inlet, the airflow suddenly expands and the airflow distribution plate acts, causing the air velocity to drop sharply. Larger dust particles naturally settle into the hopper due to gravity and inertia, while finer, lighter dust particles rise with the airflow and enter the filter chamber containing the filter bags.
As the dust-laden air flows through the filter bags, dust is trapped on the outer surface of the bags, while clean air passes through the gaps between the filter bag fibers and is discharged through the upper air outlet. As the filtration process continues, dust accumulates on the surface of the filter bag, forming a dust layer. This layer further enhances filtration effectiveness and dust removal efficiency. However, as the dust layer thickens, filtration resistance gradually increases. When this resistance reaches a certain level, a cleaning system is needed to remove dust from the filter bag surface, restoring filtration performance and allowing dust removal to resume. Common cleaning methods include pulse jet cleaning, backwash cleaning, and mechanical vibration cleaning.
Different Types of Dust Collector Filter Bags
Classification by Material
Natural fiber filter bags: Made from materials such as cotton and wool, these are relatively inexpensive and easy to process, but offer poor heat, wear, and corrosion resistance. They are generally suitable for lower temperatures and mild dust conditions and are relatively less commonly used today. Chemical Fiber Filter Bags:
Polyester (polyester) filter bags are one of the most widely used filter bags. They offer excellent wear resistance, acid resistance, and moderate heat resistance (long-term operating temperature up to 130°C). They are reasonably priced and suitable for general dust filtration in industries such as cement, power generation, and metallurgy.
Polytetrafluoroethylene (PTFE) filter bags, commonly known as the "King of Plastics," possess strong chemical stability and are resistant to corrosion from various strong acids, bases, and oxidants. They also offer excellent high-temperature resistance (long-term operating temperature up to 260°C) and self-lubricating properties. Their smooth surface resists dust pick-up and provides excellent cleaning performance, but they are more expensive. They are often used in harsh environments such as chemical processing and waste incineration.
Aramid (Nomex) filter bags offer outstanding high-temperature resistance (long-term operating temperature up to 204°C) and excellent flame retardancy. They maintain high strength even in high-temperature environments and are suitable for high-temperature applications such as asphalt mixing and carbon black production. Glass fiber filter bags: Made from glass fiber through a weaving and impregnation process, they offer advantages such as high-temperature resistance (long-term operating temperature up to 280°C), high filtration efficiency, and low resistance. However, they have poor wear resistance and flexibility, and generally require surface treatment to improve wear resistance. They are commonly used in high-temperature dusty environments such as steelmaking and smelting.
Classification by Structure
Cylindrical filter bags: The most common type, they offer a simple structure, are easy to manufacture, have a large filtration area, and are relatively easy to install and replace. They are suitable for most industrial bag dust collectors.
Flat filter bags: They take up less space, allowing for more filtration area within a dust collector of the same volume. They are suitable for applications with limited space, such as small industrial equipment or renovation projects.
Industrial bag dust collectors play a key role in industrial dust removal due to their efficient dust removal principle. Different types of dust collector filter bags offer a variety of options to suit various complex operating conditions. Understanding this knowledge will help companies select the appropriate dust collector and filter bags based on their production needs, achieving efficient dust removal and environmentally friendly production.
Post time: Sep-30-2025