Ruiz J, Kaiser A S, Lucas M
Departamento de Ingeniería Mecánica y Energía, Universidad Miguel Hernández, Avda. de la Universidad, s/n, 03202 Elche, Spain.
Departamento de Ingeniería Térmica y de Fluidos, Universidad Politécnica de Cartagena (Campus Muralla del Mar), Dr. Fleming, s/n, 30202 Cartagena, Spain.
Environ Pollut. 2017 Nov;230:422-431. doi: 10.1016/j.envpol.2017.06.073. Epub 2017 Jul 1.
Cooling tower emissions have become an increasingly common hazard to the environment (air polluting, ice formation and salts deposition) and to the health (Legionella disease) in the last decades. Several environmental policies have emerged in recent years limiting cooling tower emissions but they have not prevented an increasing intensity of outbreaks. Since the level of emissions depends mainly on cooling tower component design and the operating conditions, this paper deals with an experimental investigation of the amount of emissions, drift and PM, emitted by a cooling tower with different configurations (drift eliminators and distribution systems) and working under several operating conditions. This objective is met by the measurement of cooling tower source emission parameters by means of the sensitive paper technique. Secondary objectives were to contextualize the observed emission rates according to international regulations. Our measurements showed that the drift rates included in the relevant international standards are significantly higher than the obtained results (an average of 100 times higher) and hence, the environmental problems may occur. Therefore, a revision of the standards is recommended with the aim of reducing the environmental and human health impact. By changing the operating conditions and the distribution system, emissions can be reduced by 52.03% and 82% on average. In the case of drift eliminators, the difference ranges from 18.18% to 98.43% on average. As the emissions level is clearly influenced by operating conditions and components, regulation tests should be referred to default conditions. Finally, guidelines to perform emission tests and a selection criterion of components and conditions for the tested cooling tower are proposed.
在过去几十年中，冷却塔排放已成为对环境（空气污染、结冰和盐分沉积）和健康（军团菌病）日益常见的危害。近年来出现了几项限制冷却塔排放的环境政策，但它们并未阻止疫情爆发强度的增加。由于排放水平主要取决于冷却塔部件设计和运行条件，本文对具有不同配置（除水器和分配系统）并在几种运行条件下工作的冷却塔排放的废气、飘滴和颗粒物数量进行了实验研究。通过使用灵敏纸技术测量冷却塔源排放参数来实现这一目标。次要目标是根据国际法规将观察到的排放率置于具体情境中。我们的测量结果表明，相关国际标准中包含的飘滴率明显高于所获得的结果（平均高出100倍），因此可能会出现环境问题。因此，建议修订标准，以减少对环境和人类健康的影响。通过改变运行条件和分配系统，排放量平均可分别降低52.03%和82%。就除水器而言，差异平均在18.18%至98.43%之间。由于排放水平明显受运行条件和部件的影响，法规测试应参考默认条件。最后，提出了进行排放测试的指南以及被测冷却塔部件和条件的选择标准。
