直排式冷却水系统污垢形成原因的诊断

污垢在换热器表面的沉积会大大降低其传热效率。结合某厂实例,采用水质分析、灼烧分析、等离子体发射光谱、扫描电子显微镜等分析手段分别对冷却水水质、污垢、淤泥、微生物等的特性进行了分析。结果表明,冷却水携带淤泥是该厂冷却水系统换热器表面污垢形成的主要原因。因此建议:(1)直排式冷却水系统的日常水质监测应增加淤泥监测项目;(2)冷却水取水口应与水底保持足够距离。

DIAGNOSIS FOR CAUSES OF FOULING FORMATION IN DIRECT DISCHARGING TYPE COOLING WATER SYSTEM

The fouling deposition on surface of the heat exchanger can tremendously reduce the heat transfer efficiency of said exchanger,hence,it is very important to diagnose the causes of fouling formation.Combined with the actual example in one power plant,many analyses,such as water quality analysis,ignition analysis,plasma transmitted spectrum,and scanning electron microscopy etc.,have been carried out,to analyse the quality of cooling water,and properties in aspects of fouling,silt,and microorganism respectively.The results show that the silt carried in cooling water of the said plant is the main cause of fouling formation on the surface of heat exchanger in cooling water system.Hence,it is recommended as in the foollowing:(1) the silt should be regarded as a special item in daily quality monitoring process of the direct discharging type cooling water system;(2) the cooling water intake port should be kept enough distance from the bottom of water supply reservoir.