气体动力声:以各类风机、风管道、蒸汽管道中高压气流运动、扩容、切 流、排汽、漏气等而产生的低、中、高频各类频谱的混合而成。其中各种排汽为超高频噪声,对环境干扰最为显著。 


电磁声:电动机、励磁机、变压器以及其它电器设备、磁场交变过程中产 生的低中频噪声。 

交通噪声:厂区内运输,以及其它运输设备产生的噪声,其中喇叭、汽笛 声属高频噪声。 

其它噪声:水动力声(如冷却塔落水声)、广播、人类活动所产生的噪声。 其中冷却塔噪声对厂界外环境的影响较大,且治理难度也大。目前许多厂界噪声不能达标的电厂,多数是由于冷却塔的噪声所致。




在设计中尽可能选用低噪声设备,对磨煤机、汽轮机等设备设隔声罩,送风 机送风口和锅炉排汽口装设消音器,可减小设备的噪声强度。 


在厂区总体布置时,将噪声源较集中的主厂房布置在厂区中部,其它主要噪 声源亦尽可能远离厂界,减少电厂工业噪声对外环境的影响。



Noise problems

Mechanical power noise: it refers to the low and medium-frequency noise caused by running, vibration, friction and collision of equipment.  
Pneumatic power noise: it refers to the low, medium and high-frequency noise caused by high-pressure airflow, capacity expansion, tangential flow, exhaust steam, and air leakage in various sorts of fans, air ducts and steam tubes, among which the exhaust steam produces high-frequency noise and has remarkable influence on environment.
Combustion noise: it refers to the low and medium-frequency noise caused in the processes of combustion, vaporization, exhaust gas movement and convection in boiler.
Electromagnetic noise: it refers to the low and medium-frequency noise caused by motor, exciter, transformer and other electrical equipments in the alternating process of magnetic field.
Traffic noise: it refers to the noise caused by the transportation vehicles within the factory, among which the horn sound and the siren are of high-frequency noise.
Other noise: it refers to the noise caused by hydrodynamic force (such as the sound of cooling tower), broadcast and human activity, among which the noise of cooling tower has huge influence on the environment outside of the factory, and is hard to control. Currently,  as for most power plants which noise produced within the factory boundary fails to meet the noise control requirement , most of its noise is caused by the cooling tower.


Control over Equipment Noise
    The low-noise equipment must be given priorities as much as possible when designing; and the sound insulation hood to be particularly installed for the coal mill, steam turbine and other equipment, and  mufflers to be installed at the air supply outlet of draught fan and the exhaust gas outlet of boiler to reduce noise strength.

Rational layout
    When designing the overall layout, the buildings producing too much noise can be arranged in the center of the factory, the other noise sources can be arranged far away from the factory boundary; such layout and arrangement can help minimize the influence of industrial noise on external environment.