We evaluated four systems for recovering energy from municipal solid waste in terms of life cycle energy and CO₂ emissions. Two of these were a type of mechanical biological treatment, including a combined system of anaerobic digestion (AD) and incineration after mechanical separation, and bio-drying followed by mechanical separation for recovering solid recovered fuel (SRF). The other two systems were incineration with high rate power generation and refuse-derived fuel (RDF) recovery by a mechanical drying process. We compared the systems based on the data collected from Asahikawa City. Process flow and parameters for operation and utility consumption in the four systems were adopted from the literature. The bio-drying system showed the highest energy efficiency. It reduced the fuel material’s energy content, but improved energy efficiency due to lower electricity and fuel consumption. The RDF production system recovered the highest energy by huge evaporation, but considerable fuel consumption resulted in the lowest energy efficiency. The combined system showed a higher energy recovery than incineration, but AD was less energy efficient due to the electricity consumption. Lifecycle CO₂ emissions are closely related to energy balance. Among the various parameters, power generation efficiency and electricity consumption were highly sensitive to energy balance.

我们根据生命周期能量和 CO ₂评估了从城市固体废物中回收能量的四种系统排放。其中两种是一种机械生物处理，包括厌氧消化 (AD) 和机械分离后焚烧的组合系统，以及生物干燥后机械分离以回收固体回收燃料 (SRF)。另外两个系统是通过机械干燥过程进行高效率发电和垃圾衍生燃料 (RDF) 回收的焚烧。我们根据从旭川市收集的数据对系统进行了比较。四个系统中用于操作和公用事业消耗的工艺流程和参数均来自文献。生物干燥系统显示出最高的能源效率。它降低了燃料材料的能量含量，但由于降低了电力和燃料消耗，提高了能源效率。RDF生产系统通过巨大的蒸发回收了最高的能量，但大量的燃料消耗导致了最低的能效。组合系统显示出比焚烧更高的能量回收率，但由于耗电量，AD 的能效较低。生命周期公司₂排放与能量平衡密切相关。在各种参数中，发电效率和用电量对能量平衡高度敏感。