This study details a probabilistic life cycle assessment model to evaluate the environmental (i.e., global warming potential) and economic impact of four common sewage sludge treatment methods (anaerobic digestion, incineration, composting and pyrolysis) coupled with their most common end-of-life scenarios for the North American context. The model is subsequently applied to a realistic case study where each technology is assessed over a 10-year analysis period based on data made available by a Canadian municipality. For the case study, pyrolysis and anaerobic digestion coupled with agricultural land application have an expected global warming impact at least 46% and 60% lower, respectively, than the alternative treatment methods. Conversely, composting and pyrolysis have an expected life cycle cost at least 32% and 27% lower, respectively, than the competing treatment alternatives. Composting is able to achieve its relatively low life-cycle costs through the affordability of the required capital investments; conversely, pyrolysis is able to reduce its life-cycle cost through the recovery of valuable resources such as energy, fertilizer, and fuel. These findings and the resulting tool from this work will aid decision-makers as they seek sustainable sewage sludge treatment strategies.

本研究详细介绍了一个概率生命周期评估模型，以评估四种常见的污水污泥处理方法（厌氧消化、焚烧、堆肥和热解）以及它们最常见的寿命终止对环境（即全球变暖潜能值）和经济影响北美背景下的情景。该模型随后被应用于一个现实案例研究，其中根据加拿大市政当局提供的数据在 10 年的分析期内对每项技术进行评估。对于案例研究，热解和厌氧消化加上农业用地，预计全球变暖的影响分别比替代处理方法低 46% 和 60%。相反，堆肥和热解的预期生命周期成本分别比竞争处理方案低 32% 和 27%。通过所需资本投资的可负担性，堆肥能够实现其相对较低的生命周期成本；相反，热解能够通过回收能源、化肥和燃料等宝贵资源来降低其生命周期成本。这些发现和这项工作产生的工具将有助于决策者寻求可持续的污水污泥处理策略。