Despite the importance of wastewater treatment plants (WWTPs) to decontaminate wastewater, and consequently relieving the global freshwater reserves of industrial and domestic pollution, their effect on the air quality of the surrounding areas is often overlooked. The main aim of this work was thus to evaluate the nature and levels of common air pollutants released from different operating processes of a major WWTP in Egypt (Abu-Rawash WWTP). Concentrations of gaseous pollutants (CO, NO₂, SO₂, NH₃, H₂S, total volatile organic compounds) and particulate matter (PM_2.5, PM₁₀, and total suspended particulates) at each of the wastewater treatment operation processes within the premises were measured from September to December 2019. The intercorrelations between all pollutants were examined by principal component analysis using Minitab 17 statistical software. The results showed that the highest emission rates of gaseous pollutants were derived from the sludge thickening and dewatering process, and from the sedimentation tanks, whereas the highest levels of particulate matter were detected at the sludge handling facilities and cyclone devices. However, the recorded levels were generally lower than the maximum threshold limits set by the Egyptian Environment Laws (Law 4 of 1994 for the Protection of the Environment amended by Law 9/2009, and Law 105/2015) and the European Commission air quality guideline. This study emphasizes that the environmental impacts resulting from the direct air emissions of gases and particulates should be closely monitored if wastewater facilities are located in the vicinity of residential areas.

中文翻译：

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埃及废水处理过程排放的空气污染物评估

尽管废水处理厂 (WWTP) 对于净化废水、从而缓解全球淡水储量的工业和生活污染非常重要，但它们对周边地区空气质量的影响却常常被忽视。因此，这项工作的主要目的是评估埃及主要污水处理厂（阿布-拉瓦什污水处理厂）不同运营过程中释放的常见空气污染物的性质和水平。气态污染物（CO、NO ₂、SO ₂、NH ₃、H ₂ S、总挥发性有机化合物）和颗粒物（PM _2.5、PM _10）浓度2019年9月至2019年12月期间，测量了该场所内每个废水处理操作过程的污染物浓度（以及总悬浮颗粒物）。使用Minitab 17统计软件通过主成分分析检查了所有污染物之间的相互相关性。结果表明，气态污染物排放率最高的是污泥浓缩脱水过程和沉淀池，而颗粒物排放率最高的是污泥处理设施和旋流器装置。然而，记录的水平普遍低于埃及环境法（1994 年第 4 号环境保护法，经第 9/2009 号法和第 105/2015 号法修订）和欧盟委员会空气质量指南规定的最高阈值限制。