Novel enhanced primary treatment (EPT) of combined sewer overflow (CSO) using combinations of oxidants and coagulants

改善城市水资源管理是确保加拿大湖泊和河流可持续生态未来的关键因素，这些湖泊和河流占加拿大表面积的12%。合流下水道溢流（民间组织）贡献了大量的污染物，特别是在严重潮湿的天气条件下，由于气候变化现象，这种情况在未来几年可能会更加频繁。目前的做法是绕过民间社会组织或通过初级处理部分处理这些流量，仅通过混凝剂增强，提高了一些参数的浓度，如总悬浮固体（TSS）和大肠杆菌超出了安全排放到河流的监管要求。这种违反监管要求的行为可能会对接收的水生环境生物造成危险后果。除了受管制的污染物外，由于在各种产品中广泛使用，在民间社会组织中发现的浓度升高的微污染物和纳米材料可能对人类、鱼类和其他水生生物构成风险。因此，应评估其归宿和清除机制，并应制定战略，在其释放之前降低其浓度。为了进一步加强对CSO的处理，有必要提高初沉池的沉淀和氧化/消毒能力。在这项研究中考虑的化学添加剂将包括高铁酸盐（Fe（VI）），这是一种有前途的双重氧化剂/混凝剂和过氧乙酸（PAA）作为氧化剂与混凝剂，如硫酸铝，聚合氯化铝，或氯化铁一起应用。拟议的NSERC合作研究和发展方案将协助决策者根据对实际情况的模拟和对民间社会组织中不同污染物对环境影响的预测采取可持续发展战略。由于该CRD计划，高素质人员将接受多学科专业知识的培训，这将加强阿尔伯塔和加拿大在废水处理管理方面的能力。

Improved municipal water management is a critical element in securing a sustainable ecological future for Canadian lakes and rivers which cover about 12% of the surface area of Canada. Combined sewer overflows (CSOs) contribute a significant amount of pollutants especially at heavy wet weather conditions which may be more frequent in the coming years due to the climate change phenomenon. Current practices of bypassing the CSOs or partially treating these flows through primary treatment enhanced only by coagulants have elevated the concentrations of some parameters like total suspended solids (TSS) and E.coli beyond the regulatory requirements of safe discharge to the river. This violation to the regulatory requirements can pose dangerous consequences to the receiving aquatic environment organisms. In addition to the regulated pollutants, micropollutants (MPs) and nanomaterials (NMs) found at elevated concentrations in CSOs as a result to their extensive usage in a wide range of products can pose risks on humans, fish and other aquatic life. Consequently, their fate and removal mechanisms should be assessed, and strategies to reduce their concentrations prior to their release should be developed. In order to further enhance the treatment of CSOs, there is an essential need to enhance both the settling and the oxidation/ disinfection capabilities in primary sedimentation tanks. Chemical additions considered in this study will include ferrate (Fe(VI)) which is a promising dual oxidant/coagulant and peracetic acid (PAA) as an oxidant applied in conjunction with coagulants such as aluminum sulfate, polyaluminum chloride, or ferric chloride. The proposed NSERC Collaborative Research and Development (CRD) Program will assist decision-makers to adopt sustainable development strategies based on the simulation of actual conditions and the predictions of the impact of different pollutants in CSOs on the environment. As a result of this CRD Program, highly qualified personnel will be trained with multidisciplinary expertise that will strengthen Alberta's and Canada's capacities in wastewater treatment management.