1、 Material requirements

Material selection: The material of the dust removal filter bag should be selected according to the properties of the material being removed and the requirements of the working environment. Common materials include PPS (polyphenylene sulfide)+PTFE (polytetrafluoroethylene), polyester fiber, polypropylene fiber, glass fiber, etc. These materials should have good wear resistance, high temperature resistance, corrosion resistance and other properties.

Weight and thickness: The weight and thickness of the filter bag are also important quality indicators. For example, a dust filter bag made of PPS+PTFE material weighs approximately 550g/m ² and has a thickness between 1.8-2mm.

2、 Performance requirements for use

Working temperature: The working environment temperature of the dust removal filter bag should be ≤ 175 ℃, and the instantaneous temperature should not exceed 200 ℃. In high temperature environments, filter bags should be able to maintain stable filtration performance.

Service life: The service life of filter bags is one of the important indicators to measure their quality. Under normal environmental conditions, the filter bag should be used for no less than 30000 hours from the date of installation. If damaged within the specified time, the manufacturer shall be responsible for free replacement and shall not affect production or exceed smoke emissions standards.

Filtering efficiency: The dust removal filter bag should have good filtering effect to ensure that the concentration of flue gas emissions is ≤ 25mg/m ³. Meanwhile, the filter bag should effectively filter particles of different sizes.

3、 Technical detail requirements

Smoke temperature: The normal temperature for smoke exhaust should be between 120-160 ℃, at which point the lifespan or differential pressure of the filter material is not affected. If the exhaust temperature reaches 190 ℃, continuous operation should not exceed 5 minutes or cumulative operation should not exceed 30 minutes to ensure that the service life or differential pressure of the filter material is not affected.

Oxygen content in flue gas: The oxygen content in exhaust gas should be less than 10% to avoid adverse effects on the lifespan or differential pressure of the filter material.

Smoke flow rate: The filtration flow rate of the filter bag during operation should be controlled between 0.8-1.0m/min, with a maximum of 1.1m/min. Excessive flow rate will increase the load on the filter bag and affect its service life.

Smoke humidity: The smoke humidity should not exceed 8%. If the humidity of the flue gas is too high, the filter bag of the bag filter is prone to sticking, increasing system resistance and affecting the service life of the filter bag.

Operating differential pressure: The operating differential pressure of the bag filter should be within the range of 2400Pa to 1700Pa to ensure that the service life of the filter bag is not affected.

4、 Sewing and installation requirements

Sewing requirements: The sewing of the filter bag should be firm and the stitching should be uniform. For example, the PPS+PTFE material filter bag has a curled edge height of 60mm at the bag mouth and a reinforced layer height of 80mm at the bag bottom. The middle seam is hot-melt treated, and the rest is sewn with PTFE thread. The bag mouth expansion ring is fixed with 0.4mm stainless steel plate copper riveting, and the suture material is PTFE suture.

Installation requirements: The installation of filter bags should ensure good sealing to prevent air leakage. During the installation process, the sealing between the filter bag and the flower plate hole should be carefully checked, and it should be ensured that the filter bag skeleton is firmly fixed after being inserted into the filter bag.

5、 Other requirements

Post treatment method: To improve the wear resistance and high temperature resistance of the filter bag, it is usually subjected to post-treatment such as singeing, pressing, photothermal shaping, PTFE impregnation, etc.

Acid and alkali resistance requirements: The filter bag should have a certain degree of acid and alkali resistance to meet the usage requirements under different working conditions.

The quality standards for dust removal filter bags cover multiple aspects such as material selection, performance, technical details, sewing, and installation. By strictly following these standards, it can be ensured that the dust removal filter bag can maintain stable filtration performance and extend its service life even under harsh working conditions.