Some catering oil smoke purification equipment offers quite good purification effects. However, due to the lack of negative ion neutralization function, the concentration of negative ions in the exhaust gas is too high, causing a buildup of a large amount of charge on the surface of the exhaust outlet objects. This leads to the adsorption of pollutants, resulting in the surface of surrounding buildings near the exhaust outlet becoming black, causing severe visual pollution.

Low-altitude emission smoke purification filter acoustic film structure: Comprises materials such as leather, artificial leather, plastic film, etc., featuring impermeability, softness, and elasticity under tension, absorbing incident sound energy near resonance frequencies, typically ranging from 200 to 1000 Hz. The high sound absorption coefficient is approximately 0.3 to 0.4, generally used as an acoustic material for the mid-frequency range.