Bag filter is a dry filter device. It is suitable for capturing fine, dry, non-fibrous dust. The filter bag is made of textile filter cloth or non-woven felt, and the dust-containing gas is filtered by the filter effect of the fiber fabric. When the dust-containing gas enters the bag filter, the particles have large and significant dust due to gravity. The action settles down and falls into the ash hopper. When the gas containing fine dust passes through the filter, the dust is retained and the gas is purified. The dedusting efficiency of a new filter is generally not high enough.
There are various methods for controlling the noise of a bag filter, which can be summed up in three categories: reducing the noise of the sound source; noise control of the propagation path; and protective measures of the receiver. Which method or combination of methods is used to control bag filter noise depends on the criteria to be achieved, as well as the economic and operational considerations.
(1) noise control of bag filter dust source
The most fundamental method of noise control for bag filter is to reduce the noise of the sound source. The sound source noise control method is:
1 Reduce the excitation power of the sound source. The first is to reduce the impact caused by aerodynamic forces and eddy current noise; the second is to improve the dynamic balance accuracy of the bag filter fan impeller and shaft to reduce the noise generated by the unbalanced rotation of the bag filter fan; third is to provide good lubrication To reduce the friction; Fourth, the sound source vibration isolation. These methods can effectively reduce the incentive.
2 Reduce the response of noise radiation components in the dust removal system to the excitation force. The first is to change the natural frequency of the resonant component (when the frequency of the excitation force is equal to or close to the natural frequency of a certain component, it will evoke strong resonance of the component, which will generate intense noise); Second, the use of damping materials to increase Energy loss, reducing noise radiation.
3 correctly installed, reasonably used and maintained to prevent abnormal sound.
(2) Noise control of transmission path
1 source radiation. Use a well-designed sound enclosure around the noise source or around the receiver to keep the sound source sealed and prevent or reduce outward propagation of the bag filter noise source.
2 sound absorption. Using the sound absorption principle and using good absorbent materials, the bag filter noise is continuously attenuated in the transmission path.
3 sound reflections. Using the sound reflection principle, using a discontinuous structure, the sound energy is reflected to the sound source and the noise of the bag filter is blocked.
(3) Protective measures of the receiver
The receiver may be a collection of one person or several people, or a noise-sensitive device. Can use earplugs, earmuffs or set the soundproof wall, soundproof room, so that the noise is controlled to allow the level to prevent the bag filter noise hazards.