There is little knowledge regarding the environmental sustainability of domestic on-site or decentralised wastewater treatment systems (DWWTS). This study evaluated six unique life cycle environmental impacts for different DWTTS configurations of five conventional septic tank systems, four packaged treatment units, and a willow evapotranspiration system. Similar freshwater eutrophication (FE), dissipated water (DW), and mineral and metal (MM), burdens were noted between the packaged and conventional system configurations, with the packaged systems demonstrating significantly higher impacts of between 18% and 56% for climate change (CC), marine eutrophication (ME), and fossils (F). At a system level, higher impacts were observed in systems requiring (i) three vs. two engineered treatment stages, (ii) a larger soil percolation trench area, and (iii) pumping of effluent. The evapotranspiration system presented the smallest total environmental impacts (3.0–10.8 lower), with net benefits for FE, ME, and MM identified due to the biomass (wood) production offsetting these burdens. Further analysis highlighted the sensitivity of results to biomass yield, operational demands (desludging or pumping energy demands), and embodied materials, with less significant impacts for replacing mechanical components, i.e., pumps. The findings highlighted the variation in environmental performance of different DWTTS configurations and indicated opportunities for design improvements to reduce their life cycle impacts.

中文翻译：

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家庭现场或分散式污水处理系统的生命周期环境性能

关于家庭现场或分散式废水处理系统 (DWWTS) 的环境可持续性知之甚少。本研究评估了五个传统化粪池系统、四个成套处理单元和柳树蒸散系统的不同 DWTTS 配置的六个独特的生命周期环境影响。类似的淡水富营养化 (FE)、耗散水 (DW) 以及矿物和金属 (MM)，在打包系统配置和传统系统配置之间注意到了负担，打包系统对气候变化的影响显着提高了 18% 到 56% (CC)、海洋富营养化 (ME) 和化石 (F)。在系统层面，在需要 (i) 三个与两个工程处理阶段的系统中观察到更高的影响，(ii) 更大的土壤渗透沟面积，(iii) 抽吸污水。蒸散系统的总环境影响最小（低 3.0-10.8），由于生物量（木材）生产抵消了这些负担，因此确定了对 FE、ME 和 MM 的净收益。进一步的分析强调了结果对生物质产量、操作需求（去除淤泥或泵送能量需求）和具体材料的敏感性，对更换机械部件（即泵）的影响较小。调查结果强调了不同 DWTTS 配置的环境性能差异，并指出了设计改进以减少其生命周期影响的机会。和 MM 确定是由于生物量（木材）生产抵消了这些负担。进一步的分析强调了结果对生物质产量、操作需求（去除淤泥或泵送能量需求）和具体材料的敏感性，对更换机械部件（即泵）的影响较小。调查结果强调了不同 DWTTS 配置的环境性能差异，并指出了设计改进以减少其生命周期影响的机会。和 MM 确定是由于生物量（木材）生产抵消了这些负担。进一步的分析强调了结果对生物质产量、操作需求（去除淤泥或泵送能量需求）和具体材料的敏感性，对更换机械部件（即泵）的影响较小。调查结果强调了不同 DWTTS 配置的环境性能差异，并指出了设计改进以减少其生命周期影响的机会。