During secondary effluent ozonation, real-time control of the ozone dose based on the water quality is essential to minimize operational costs and by-product formation (i.e. two of the main hurdles hindering a fast implementation of the technology). In this pilot-scale study, the ozone dose was controlled via online UV absorbance (UVA₂₅₄) measurements. Only one sensor was used although a ΔUVA₂₅₄-based control strategy was applied. The practical implications of online spectral sensors and the effect of effluent dynamics in terms of load (i.e. Dissolved Organic Carbon or DOC concentration) and composition (i.e. reactivity) was studied in relation to the applied control strategies. The one sensor approach – presented for the first time to the best of the authors’ knowledge – reduced the negative impact of sensor fouling. The use of manual and ultrasonic cleaning is recommended as it results in significantly less fouling (i.e. a factor of 6 difference). Additionally, the variable effluent reactivity showed to be more influential than the effluent load in determining the ozone dose. The use of ΔUVA₂₅₄ ensured the supply of the required ozone doses during varying water quality and weather conditions, and at lower operational costs than more common control strategies (up to 22% of savings). Flow or load proportional strategies were not able to cope with the dynamic ozone demand of the effluent. However, the required additional response time of the ΔUVA₂₅₄-strategy might be a disadvantage and could be tackled using hybrid control approaches including load-based dosing (i.e. O₃:DOC ratio based) and the use of a combined feedback-feedforward system.

在二次废水臭氧化过程中，基于水质实时控制臭氧剂量对于最小化运营成本和副产物形成至关重要（即两个主要障碍阻碍了该技术的快速实施）。在这项中试规模的研究中，臭氧剂量是通过在线紫外线吸收率（UVA ₂₅₄）测量来控制的。仅一个传感器，使用虽然ΔUVA ₂₅₄基于控制策略的应用。结合应用的控制策略，研究了在线光谱传感器的实际含义以及废水动力学对负荷（即溶解的有机碳或DOC浓度）和成分（即反应性）的影响。据作者所知，首次采用单传感器方法减少了传感器结垢的负面影响。建议使用手动和超声波清洗，因为这样可以大大减少结垢（即相差6倍）。此外，在确定臭氧剂量时，可变的废水反应性比废水负荷更具影响力。使用ΔUVA的₂₅₄确保在不同的水质和天气条件下提供所需的臭氧剂量，并且比更常见的控制策略以更低的运营成本（节省多达22％的成本）。流量或负荷比例策略无法应对废水中动态的臭氧需求。然而，ΔUVA的所需的附加反应时间₂₅₄ -strategy可能是一个缺点，并且可以使用混合控制加以处理方法，包括基于负载的给药（即ø ₃：基于DOC比），并且使用的组合反馈前馈系统的。