Unconventional wastewater management systems have been developed to cope with the ever-increasing demand on the existing infrastructure. Grey water separation and treatment emerged to address the limitations of conventional sanitation systems. Towards achieving key sustainable development goals, this study aims to assess the performance of grey and black water separation alternatives with on-site treatment (SOT) or dual collection (SDC), compared to conventional collection and treatment (CCT). The on-site treated grey water in the SOT scenario was used for toilet flushing, leading to 25% reduction in domestic water demand. A novel manhole configuration was designed to suit the dual sewer collection network in the SDC scenario, where the sewer-collected grey water was conveyed directly to the tertiary treatment stage due to its low solids and organic load. A comprehensive, cost-integrated life cycle analysis was carried out to quantify the environmental impacts and assess the financial feasibility of the examined wastewater management systems. An eco-efficiency analysis was conducted to aggregate the results of life cycle costing (LCC) and life cycle assessment (LCA). The proposed collection and treatment alternatives were applied on a residential development in Dubai based on local design guidelines. Results of the environmental assessment indicated that SOT had the highest impacts in all midpoint impact categories with a single score of 1.27, followed by CCT (0.94) and SDC (0.89) systems. Over 50-year assessment period, the LCC findings revealed close net present values of CCT and SDC systems ($30 and 25 million, respectively), compared to SOT system ($8 million). The environmental impacts and financial burdens of the SOT system were reduced by 54 and 59%, respectively, when the treated grey water was reused instead of potable water for toilet flushing. The eco-efficiency analysis indicated that the SDC is the most sustainable system. Overall, this research emphasized the potential environmental and financial benefits of grey water separation, collection and treatment systems taking into consideration the entire urban water cycle.

非常规废水管理系统已经开发出来，以应对对现有基础设施不断增长的需求。灰水分离和处理的出现是为了解决传统卫生系统的局限性。为了实现关键的可持续发展目标，本研究旨在评估采用现场处理 (SOT) 或双重收集 (SDC) 的灰水和黑水分离替代方案与传统收集和处理 (CCT) 相比的性能。SOT 情景中的现场处理灰水用于冲厕，导致生活用水需求减少 25%。设计了一种新颖的检修孔配置，以适应 SDC 场景中的双下水道收集网络，由于其低固体和有机负荷，下水道收集的灰水被直接输送到三级处理阶段。进行了综合成本综合生命周期分析，以量化环境影响并评估所检查废水管理系统的财务可行性。进行生态效率分析以汇总生命周期成本计算 (LCC) 和生命周期评估 (LCA) 的结果。根据当地设计准则，提议的收集和处理替代方案已应用于迪拜的住宅开发项目。环境评估结果表明，SOT 在所有中点影响类别中的影响最高，单项得分为 1.27，其次是 CCT (0.94) 和 SDC (0.89) 系统。超过50年的评估期，LCC 的调查结果显示，与 SOT 系统（800 万美元）相比，CCT 和 SDC 系统的净现值接近（分别为 30 和 2500 万美元）。当处理后的灰水代替饮用水用于冲厕所时，SOT 系统的环境影响和财务负担分别减少了 54% 和 59%。生态效率分析表明，SDC 是最可持续的系统。总的来说，这项研究强调了考虑到整个城市水循环的灰水分离、收集和处理系统的潜在环境和经济利益。当处理过的灰水代替饮用水用于冲厕所时。生态效率分析表明，SDC 是最可持续的系统。总的来说，这项研究强调了考虑到整个城市水循环的灰水分离、收集和处理系统的潜在环境和经济利益。当处理过的灰水代替饮用水用于冲厕所时。生态效率分析表明，SDC 是最可持续的系统。总的来说，这项研究强调了考虑到整个城市水循环的灰水分离、收集和处理系统的潜在环境和经济利益。