Because of the high thickness of bug dust and high humidity in the air draft alleyway of axial flow ventilators,the former muffler used by Mine JingGezhuang is jammed.

• 荆各庄主要通风机主扇排风通道环境恶劣,粉尘浓度高、湿度大,致使原消声设备降噪效果不明显。