Department of Environmental Engineering, Technical University of Denmark, Miljoevej, Building 113, DK-2800 Kongens Lyngby, Denmark.
Waste Manag. 2011 Jul;31(7):1597-605. doi: 10.1016/j.wasman.2011.03.001. Epub 2011 Mar 29.
CO(2)-loads from combustible waste are important inputs for national CO(2) inventories and life-cycle assessments (LCA). CO(2) emissions from waste incinerators are often expressed by emission factors in kg fossil CO(2) emitted per GJ energy content of the waste. Various studies have shown considerable variations between emission factors for different incinerators, but the background for these variations has not been thoroughly examined. One important reason may be variations in collection of recyclable materials as source separation alters the composition of the residual waste incinerated. The objective of this study was to quantify the importance of source separation for determination of emission factors for incineration of residual household waste. This was done by mimicking various source separation scenarios and based on waste composition data calculating resulting emission factors for residual waste routed to incineration. Emission factors ranged from 27 to 40 kg CO(2)/GJ. The results appeared most sensitive towards variations in waste composition and water content. Recycling rates and lower heating values could not be used as simple indicators of the resulting emission factors for residual household waste; however the fossil carbon ratio of the waste after source separation was found to be appropriately correlated with the emission factor. Based on the results, it is recommended to carefully evaluate the source separation and collection systems behind reported literature values when comparing different studies and when using the values for environmental assessment purposes.
燃烧废物产生的 CO(2) 负荷是国家 CO(2) 清单和生命周期评估 (LCA) 的重要投入。废物焚烧厂的 CO(2) 排放通常以每吉焦废物能量含量排放的化石 CO(2) 千克表示的排放因子来表示。各种研究表明，不同焚烧炉的排放因子存在相当大的差异，但这些差异的背景尚未得到彻底研究。一个重要原因可能是可回收材料的收集方式存在差异，因为源头分类会改变焚烧的残余废物的组成。本研究的目的是量化源头分类对确定残余家庭废物焚烧排放因子的重要性。这是通过模拟各种源头分类情景，并根据废物组成数据计算送往焚烧的残余废物的相应排放因子来实现的。排放因子范围为 27 至 40 千克 CO(2)/GJ。结果似乎对废物组成和含水量的变化最为敏感。回收率和低位热值不能用作残余家庭废物排放因子的简单指标；然而，经过源头分类后的废物的化石碳比与排放因子呈适当相关。基于研究结果，建议在比较不同研究和将这些值用于环境评估目的时，仔细评估报告文献值背后的源头分类和收集系统。
