双曲线自然通风冷却塔淋水噪声的治理

Water-spouting Noise Elimination of Hyperbolic Natural-draft Cooling Tower

针对天津国华盘山发电有限责任公司2×500MW火电机组建造的双曲线冷却塔投用后造成的噪声污染进行了分析，冷却塔噪声频谱表现为中高频特性，夜间西厂界噪声值为73.2-80.1dB（A），超出Ⅱ类标准23.2-30.1dB（A）；区域环境噪声值为52.5-64.7dB（A）.超出Ⅱ类标准2.5-14.7dB（A）。文章提出噪声治理方案，就单个方案及多方案联合进行了综合分析，并结合噪声预测软件CADNA／A的效果预测，最终选定了最优实施方案，即“库房＋隔声屏＋消声装置”。项目实施后，实测区域环境噪声值为：昼间44.7-50.7dB（A）；夜间42.8-49.0dB（A），均达到了Ⅱ类标准，且进一步证明了预测的准确性，也为我国针对双曲线自然通风冷却塔淋水噪声治理提供借鉴。

Noise contamination rose after the commission of the hyperbolic natural-draft cooling tower constructed for 2500MW coal-fired unites of Tianjin Guohua Panshan generation Co. Ltd.. The noise source of the cooling tower was analyzed and studied. The noise mainly ranges in the middle and high frequencies. Nightly monitor result range of west boundary was from 73.2dB（A） to 80.1dB（A）. The superseale was from 23.2dB（A） to 30.1dB（A）. And result range of regional environmental noise out of west boundary was from 52.5dB（A） to 64.7dB（A）. The superseale was from 2.5dB（A） to 14.7dB（A）. The plans of the noise treatment were given. And the analysis was also brought forward, which ineluding single and united plan. Combining with the field forecast for the effect using software CADNA/A, the best plan was selected. The plan was to build depot, on which there were sound barriers, and to set noise suppressors in cistern of cooling tower. The field test of accomplished project was made and the results were given. Daytime monitor result range of regional environmental noise out of west boundary was from 44. 7dB（A） to 50.7dB（A）, and nightly monitor result range was from 42.8dB（A） to 49.0dB（A）. Both results meet level-Ⅱ standard and are according with forecast. The valuable experiences achieved in the water-spouting noise treatment for hyperbolic natural-draft cooling tower will provide a guidance for construction of similar cooling tower.