How to choose filter bags depending on the cleaning method?

The selection of filter bags should be based on the properties of dust, such as viscosity, humidity, acidity, particle size distribution, fire resistance, etc. Alternatively, the selection can be based on the properties of flue gases, such as temperature and humidity, acidity, oxygen content, dust concentration, and cleaning factors such as cleaning method, cleaning pressure and cleaning interval. Today we will discuss how to select filter bags according to cleaning method.

1. Pulse Blowing Method: The kinetic energy expended on dust in this filter bag cleaning method is between high-energy and low-intensity kinetic energy types, which requires the dust collection bag to be soft and also have a certain rigidity. When using cloth dust bags, satin and twill fabrics are preferred, but from the perspective of dust removal efficiency, filtration speed and frame wear resistance, it is advisable to use needle felt, and needle felt with a density of 300-600 g / m2 should be selected. Woven fabrics are rarely used. If it is really necessary, several surface treatment operations should be carried out;

2. Pulse jet cleaning method: This filter bag cleaning method uses the highest kinetic energy to remove the dust layer, and is a typical external filtration cleaning method. The pressure of fine dust is very large, and the residual amount of dust attached to the threads of the dust bag is relatively small. The dust bags used are mainly made of felt or needle felt. Under the action of the pulse jet, the dust bag is instantly deformed strongly, causing greater stress, so filter materials with high tensile strength are used. The dust bag often rubs against the frame, so wear-resistant dust bags and fabric dust bags should be used.

3. Vibration cleaning method: The main feature of this cleaning method with a filter bag is that the kinetic energy applied to the dust layer is less than that of the pulse jet and reverse blowing. This is a low-energy cleaning method, so fabric dust bags should be used. Soft fabric transmits vibration waves better;

4. Air ring spray cleaning method: Since the cleaning performance of this dust bag is very good, the dust bag must have very good rigidity, fine porosity and good wear resistance, so that the dust bag will not change and fluff when moving up and down in the air spray ring. Therefore, it is necessary to use felt or needle felt. High-density thick felt is also required. The basic weight of the fabric should be 600-800g/m2.

5. Reverse blow-vibration cleaning method: The kinetic energy applied to the dust layer in this dust bag cleaning method is low energy. In the early stage, cloth dust bags were the most common. At present, most of them use needle felt. The main reason is to improve the filtration speed. Needle felt requires a fabric density of 280-350g/m2, a thickness of 1.0-1.3mm, and good air permeability. When sewing and installing dust bags, we generally tighten the dust bags and avoid stretching in the filtration specifications. When the dust bags are stretched by about 2%, the effect of the cleaning method will be worse.

6. Reverse blowing cleaning method (reverse suction bag shrinkage): This dust bag cleaning method mainly uses cloth dust bags, and felt materials with lighter weight, rich softness, and lower technical specifications can also be used. Among them, fiberglass dust bags are mainly used, and they are most commonly used in large and medium-sized bag dust bags. There are quantitative requirements for lifting and sewing dust bags. If they are not taken seriously, it will have a relatively large negative impact on the service life of dust bags. Therefore, when refining and recycling dust bags, we generally take the technical conditions into full account to avoid the elongation of dust bags.

The above are 6 points to pay attention to when choosing filter bags depending on the cleaning method. However, when choosing filter bags, you should not only consider the cleaning method, but also the nature of the dust, the nature of the flue gases and the dust removal system. Only then can you choose the right filter bag.