Drinking water utilities are increasingly facing the challenges of maintaining water quality, and simultaneously complying with conflicting regulatory standards. One such challenge is the dosage of chlorine-based disinfectants which is typically regulated to prevent microbial growth in the water distribution systems, while limiting disinfection by-products (DBPs). On the other hand, chlorine residuals also influence the dissolution of lead into drinking water from corrosion scales in the pipe internals, as has been shown by previous studies. Hence, it is important to consider water lead levels (WLLs) while determining the appropriate chlorine dosage. This study proposes a multi-objective optimization framework to understand and balance the trade-offs between (i) minimizing total disinfectant dosage to reduce DBPs formation potential, and (ii) maximizing the volume of safe drinking water supply with respect to both WLLs and residual free chlorine concentrations. The approach comprises of the development of a dynamic simulation-optimization framework to account for the impact of spatial and temporal variations of network hydraulics and water chemistry on WLLs and residual free chlorine. The framework couples dynamic multi-species water quality simulations (pH, residual free chlorine, dissolved inorganic carbon, and orthophosphate concentration) with a multi-objective genetic optimization algorithm in an integrated MATLAB-EPANET-MSX platform. The application of the optimization formulation is demonstrated on a real-world distribution network case study. The resulting optimal solution set on pareto-plots are discussed for sensitivity of the trade-offs between the two objective functions, under various water chemistry conditions that have been suggested in earlier studies for minimizing lead release from plattnerite (PbO₂) corrosion scales in lead service lines. The resulting optimal disinfectant dosage schedule, for pumping and booster station nodes in each case, provided insights on maintaining disinfectant residuals throughout the distribution system so as to prevent microbial growth as well as lead contamination events while limiting DBPs formation. Further, environmental implications related to the use of the proposed framework are also discussed.

饮用水公用事业正日益面临维持水质并同时遵守相互矛盾的法规标准的挑战。一个这样的挑战是基于氯的消毒剂的剂量，通常对其进行调节以防止水分配系统中的微生物生长，同时限制消毒副产物（DBP）。另一方面，如先前的研究所示，氯残留物也会影响铅从管道内部的腐蚀垢溶解到饮用水中。因此，在确定适当的氯剂量时，必须考虑水铅含量（WLL）。这项研究提出了一个多目标优化框架，以了解和平衡（i）最小化消毒剂的总用量以减少DBP的形成潜力，（ii）相对于WLL和残留的游离氯浓度，最大化安全饮用水的供应量。该方法包括开发动态仿真优化框架，以解决网络水力和水化学的时空变化对WLL和残留游离氯的影响。该框架在集成的MATLAB-EPANET-MSX平台中将动态多物种水质模拟（pH，残留游离氯，溶解的无机碳和正磷酸盐浓度）与多目标遗传优化算法结合在一起。在一个实际的分销网络案例研究中演示了优化公式的应用。₂）铅服务线中的腐蚀水垢。在每种情况下，针对泵站和增压站节点产生的最佳消毒剂剂量表，为在整个分配系统中保持消毒剂残留物提供了见解，从而在限制DBP形成的同时防止了微生物的生长以及铅污染。此外，还讨论了与使用拟议框架有关的环境影响。