Vaccari M, Foladori P, Nembrini S, Vitali F
Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, via Branze 43, 25123 Brescia, Italy.
Department of Civil, Environmental and Mechanical Engineering, University of Trento, via Mesiano 77, 38123 Trento, Italy E-mail:
Water Sci Technol. 2018 May;77(9-10):2242-2252. doi: 10.2166/wst.2018.035.
One of the largest surveys in Europe about energy consumption in Italian wastewater treatment plants (WWTPs) is presented, based on 241 WWTPs and a total population equivalent (PE) of more than 9,000,000 PE. The study contributes towards standardised resilient data and benchmarking and to identify potentials for energy savings. In the energy benchmark, three indicators were used: specific energy consumption expressed per population equivalents (kWh PE year), per cubic meter (kWh/m), and per unit of chemical oxygen demand (COD) removed (kWh/kgCOD). The indicator kWh/m, even though widely applied, resulted in a biased benchmark, because highly influenced by stormwater and infiltrations. Plants with combined networks (often used in Europe) showed an apparent better energy performance. Conversely, the indicator kWh PE year resulted in a more meaningful definition of a benchmark. High energy efficiency was associated with: (i) large capacity of the plant, (ii) higher COD concentration in wastewater, (iii) separate sewer systems, (iv) capacity utilisation over 80%, and (v) high organic loads, but without overloading. The 25th percentile was proposed as a benchmark for four size classes: 23 kWh PE y for large plants > 100,000 PE; 42 kWh PE y for capacity 10,000 < PE < 100,000, 48 kWh PE y for capacity 2,000 < PE < 10,000 and 76 kWh PE y for small plants < 2,000 PE.
本文展示了欧洲关于意大利污水处理厂（WWTPs）能源消耗的最大规模调查之一，该调查基于241座污水处理厂，总人口当量（PE）超过900万PE。该研究有助于生成标准化的弹性数据并进行基准测试，以确定节能潜力。在能源基准测试中，使用了三个指标：按人口当量计算的特定能耗（kWh/PE·年）、按立方米计算的特定能耗（kWh/m³）以及按去除的单位化学需氧量（COD）计算的特定能耗（kWh/kgCOD）。kWh/m³指标尽管应用广泛，但由于受雨水和渗漏影响较大，导致基准测试存在偏差。采用合流制管网的工厂（在欧洲经常使用）显示出明显更好的能源绩效。相反，kWh/PE·年指标对基准的定义更有意义。高能效与以下因素相关：（i）工厂规模大；（ii）废水中COD浓度高；（iii）分流制排水系统；（iv）产能利用率超过80%；（v）有机负荷高，但不过载。建议将第25百分位数作为四个规模等级的基准：对于规模大于100,000 PE的大型工厂为23 kWh/PE·年；对于产能10,000 < PE < 100,000的工厂为42 kWh/PE·年；对于产能2,000 < PE < 10,000的工厂为48 kWh/PE·年；对于规模小于2,000 PE的小型工厂为76 kWh/PE·年。
